Today, the scope of application of electric motors is very wide, and one of the most popular and used types of motor is the asynchronous electric motor. But the asynchronous electric motor itself is divided into two types:

with a short-circuited rotor winding (short-circuited rotor), wound rotor;
Schrage-Richter engine (powered from the rotor side).

Application of asynchronous electric motors

Asynchronous motors can operate in two operating modes: as a generator and as an electric motor. This shows that they can be used as a source of electric current in autonomous mobile power sources.

The use of asynchronous motors as traction force is more extensive and affects many areas of human activity. They have found wide application both in low-power household electrical appliances and in technological equipment of enterprises and agriculture.

Types of main faults, their diagnosis and necessary repairs of an asynchronous electric motor

Despite the fact that asynchronous electric motors have high reliability and low manufacturing costs, which determines their popularity, they nevertheless fail. Some electric motor malfunctions can only be diagnosed using specialized equipment and require repair in a factory for the production and repair of electric motors. However, there are faults that you can diagnose yourself and which can be eliminated in your production conditions.

One of these malfunctions is that the electric motor does not reach normal speed when starting up or does not rotate. The causes of this malfunction may be electrical or mechanical in nature. Electrical reasons include an internal break in the rotor or stator winding, a broken connection in the starting equipment, or a break in the supply network. If there is a break in the internal windings of the motor, if they are connected in a “delta” pattern, then you must first open them. After this, using a megohmmeter, the phase in which the break occurred is determined. After determining the break, the motor winding is rewound and reassembled and installed in place.

Low voltage in the network, poor contacts in the rotor winding or high resistance in the rotor circuit of an electric motor with a wound rotor leads to the fact that the rotation speed of the electric motor at full load is lower than the rated one. Bad contacts in the winding are detected by applying voltage (20 -25% of the nominal) to the stator of the electric motor. In this case, the locked rotor is turned manually and the current strength in all phases of the stator is checked. In a working rotor, the current strength is the same in all positions. If the contact in the soldering of the frontal parts is broken, a voltage drop will be noted. The maximum permissible difference in readings should not exceed 10%.

Deployment of the electric motor with the wound rotor circuit open. The cause of this malfunction is a short circuit in the rotor winding. This malfunction can be detected by careful external inspection, as well as by measuring the insulation resistance of the rotor winding. If the inspection does not produce results, then it is determined by determining uneven heating of the rotor winding. In this case, the rotor is braked, and a reduced voltage is supplied to the stator.

Uniform heating of the electric motor above the permissible norm occurs due to prolonged overload and deterioration of the cooling system. This malfunction leads to premature wear of the winding insulation.

Local heating of the stator winding occurs due to a short circuit of the winding to the housing in 2 places, erroneous connection of the coils in any phase, a short circuit between 2 phases or a short circuit between the turns of the winding in one of the phases of the stator winding. This malfunction can be diagnosed by reducing the rotation speed of the electric motor, a strong hum, or the smell of overheated insulation. The damaged winding is determined by measuring the resistance (the damaged phase has less resistance), or by measuring the current when a reduced voltage is supplied.

When connecting the windings in a star configuration, the current in the damaged phase will be higher than in the others. In the case of using a “triangle”, the line current in healthy wires will have a higher value.

Burnout or melting of steel that occurs when the stator winding is short-circuited, steel sheets are short-circuited due to the stator touching the rotor, or due to insulation failure leads to local heating of the active steel of the rotor. In this case, smoke appears, a burning smell, sparks appear, and the engine hum intensifies. This malfunction occurs due to wear or incorrect installation of bearings, strong vibration or one-sided attraction of the rotor to the stator (turn short circuits in the stator winding).

REMINDER

for the operation of asynchronous electric motors with voltages up to 1000 V.

1. General part.

1. Asynchronous electric motors can develop their rated power with voltage fluctuations in the network of 5% of the rated value and the air cooling temperature not exceeding +35 o C.

2. Asynchronous electric motors at a cooling air temperature below +35 o C, after special tests, can be overloaded with current up to 5%, while the temperature of the main components of the electric motor (windings, iron, bearings) should not exceed the values specified below.

3. Overloading the electric motor with current greater than 5% is not permissible under any temperature conditions.

4. Electric motors and the mechanisms they drive must be marked with arrows indicating the direction of their rotation, and the unit to which it belongs must be indicated on the engine starting device.

5. The design of the electric motor and its control and measuring equipment must comply with the environmental conditions according to the type of design.

6. The housing of electric motors and starting equipment must be reliably grounded.

7. Rotating parts of electric motors and parts connecting electric motors to mechanisms (clutches, pulleys) must be protected from accidental touches.

8. Electric motor housings made of materials susceptible to corrosion and without special coatings (enamel, oxidation, etc.) must be painted.

9. To monitor the start-up and operation of electric motors of mechanisms, regulation of the technological process, which is carried out according to the current value, an ammeter must be installed on the starting board or panel, measuring the current in the stator circuit of the electric motor.

10. The cable sleeve or pipe with the cable laid in it must fit directly into the terminal box of the electric motor, or the cables or wires in the unprotected area must have additional insulation and protection from mechanical damage (flexible metal wires, fences).

2. Operation of electric motors.

1. Electric motors with voltages up to 1000 V are switched on by the person servicing the mechanism being driven.

2. Assembly and disassembly of the electrical circuit of electric motors in preparation for start-up or repair is carried out by the shop electrician on duty at the direction of the shift supervisor (shift foreman) or the person responsible for servicing the driven mechanism.

3. Before putting the electric motor into operation, it is necessary to check: the cleanliness of the electric motor, the absence of foreign objects on it or near it, the reliability of fastening of the fences, the serviceability of grounding, the presence and tightness of fasteners.

4. After turning on the electric motor and during its operation, you must check:

a) temperature of the electric motor housing - heating, which should not exceed 90 o C;

b) heating temperature of the bearings, which should be no more than 90 ° C for rolling bearings and 70 ° C for plain bearings;

c) lubrication of plain bearings;

d) vibration of electric motor bearings, which under all permissible modes should not exceed 0.1 mm for electric motors 1500 rpm, 0.05 mm for electric motors 3000 rpm, 0.13 mm for 1000 rpm, 0.17 mm for electric motors 750 rpm and below;

e) the axial spread of electric motor rotors should be no more than 2-4 mm for plain bearings; f) absence of knocks and extraneous noise in the bearings and engine;

g) load of electric motors (by ammeters, if any);

f) the operation of slip rings and brushes on electric motors with a wound rotor.

5. Electric motors that do not provide starting mechanisms under load must be turned on after unloading the driven mechanisms.

6. Electric motors that have been in reserve for a long time must be constantly ready for immediate start-up, periodically inspected and tested according to the approved schedule.

7. Checking the condition and operating modes of engines by operational personnel (electrician on duty) is carried out during equipment inspections, but at least 2 times per shift.

8. All noticed defects and abnormal operation of electric motors must be recorded in the operational log and the equipment defect log, the shift supervisor and, during the daytime, the workshop energy engineer must be notified.

9. Minor defects and malfunctions are eliminated by the electrician on duty in compliance with the relevant safety rules.

10. The electric motor is emergency (immediately) disconnected from the network in the following cases:

a) the appearance of smoke or fire from the electric motor or it;

b) an accident with a person;

c) vibration in excess of permissible norms, threatening the integrity of the electric motor;

d) failure of the driven mechanism;

e) a strong decrease in speed, accompanied by strong heating of the electric motor.

In other cases, the electric motor is disconnected from the network after starting the backup unit or with the permission of the shift supervisor.

11. Protection of the electric motor must be carried out in accordance with the “Rules for Electrical Installations”.

Fuse links protecting power and control circuits must be calibrated indicating the rated current.

It is prohibited to use uncalibrated fuse-links without marking the rated current value.

12. Before putting into operation electric motors, critical positions or those that are in reserve for a long time (from a month or more), it is necessary to check the insulation resistance of the motor windings with a megger in accordance with the “Rules for the operation of consumer electrical installations” (PTEEP). The resistance must be at least 1 MOhm, for hot machines at least 0.5 MOhm.

For electric motors with a power above 100 kW, the absorption coefficient is measured, the value of which is at least 1.3.

3. Safety precautions when servicing electric motors.

When servicing electric motors, the following rules must be observed:

1. When servicing electric motors, women must wear a hat and overalls. Servicing electrically driven units while wearing women's clothing is not permitted.

2. When the electric motor is running, it is prohibited to remove the guards and penetrate behind them.

3. Insulating the rotor rings may only be done using pads made of insulated material.

4. It is prohibited to carry out any work in the circuits of operating (rotating) electric motors and their starting and control equipment, with the exception of work in the rheostat circuit and test work carried out according to special approved programs that provide for the necessary safety measures.

5. Only operating personnel with an electrical safety group of at least III are allowed to open starting devices (cabinets, drawers, etc.) that are energized to inspect them.

6. Work in starting devices can be carried out at full voltage.

7. Preparation for repairing the electric motor and allowing repair personnel to work must be carried out in strict accordance with safety rules, and attention should be paid to eliminating the possibility of rotation of the shaft (stator) of the electric motor from the side of the driven mechanism.

8. When repairing the drive mechanism, the electric motor must be disconnected from the network, its circuit is completely disassembled, the power cable is disconnected from the electric motor and portable grounding is installed at its ends. If it is impossible to install portable grounding at the ends of the cable, all its current-carrying parts are connected together with a bolt and insulated. All drives, keys, and buttons that can supply voltage to the engine of the mechanism being repaired must have locks installed and posters posted in accordance with safety rules.

9. . Repair of electric motors and their starting and control equipment is carried out, as a rule, with repair of the drive mechanism.

All documents presented in the catalog are not their official publication and are intended for informational purposes only. Electronic copies of these documents can be distributed without any restrictions. You can post information from this site on any other site.

BRANCH OF JSC "ENGINEERING CENTER UES" - "FIRM ORGRES"

STANDARD INSTRUCTIONS
ON OPERATION OF ELECTRIC MOTORS IN INSTALLATIONS OF OWN NEEDS OF POWER PLANTS

SO 34.45.509-2005

Moscow 2005

Developed by:Branch of OJSC "Engineering Center UES" - "Company ORGRES"

Executor: V.A. VALITOV

Approved:Chief Engineer of the Branch of OJSC "Engineering Center UES" - "Company ORGRES" V.A. KUPCHENKO 08/04/2005

The period for the first inspection of this RS is 2010, inspection frequency is once every 5 years

Keywords: electric motor, mechanism, insulation, winding, bearing, personnel, maintenance, start-up, shutdown

STANDARD INSTRUCTIONS FOR THE OPERATION OF ELECTRIC MOTORS IN INSTALLATIONS OF OWN NEEDS OF POWER PLANTS

SO 34.45.509-2005

Put into effect
from 01.09.2005

The standard instructions apply to asynchronous and synchronous electric motors with a power of over 1 kW, used to drive auxiliary mechanisms of power plants with a voltage of 0.4 kV; 3.15kV; 6.0 kV and 10 kV, as well as DC electric motors used to drive fuel feeders, emergency turbine oil pumps and shaft seals of hydrogen-cooled turbogenerators.

This Standard Instruction is the basis for drawing up local instructions at each power plant, which must take into account the specific conditions of the electric motors being operated, the requirements and recommendations of the manufacturers.

With the publication of this Standard Instruction the following become invalid:

“Standard instructions for the operation of electric motors in auxiliary installations of power plants: RD 34.45.509-91” (M.: SPO ORGRES, 1991);

“Standard operating instructions for large electric motors with water-cooled rotors for driving feed pumps: RD 34.45.507” (M.: SPO Soyuztekhenergo, 1989);

“Standard operating instructions for synchronous electric motors of ball mills Ш-50: TI 34-70-023-86” (Moscow: SPO Soyuztekhenergo, 1986).

1 General requirements

1.1. All electric motors installed in the technological workshops of a power plant must have an abbreviated marking on the body, common with the mechanism and corresponding to the executive operating process diagram, and an indicator of the direction of rotation. Buttons or keys for controlling switches (circuit breakers or magnetic starters) of electric motors must have clear inscriptions indicating which electric motor they relate to, as well as which button or which direction of turning the key relates to starting and which to stopping the electric motor. Marking of switching devices, buttons and control keys must be carried out by electrical shop personnel.

The keys of automatic transfer switches and technological interlocks must have inscriptions indicating their operating position (operation, automation, reserve, interlocked, etc.). On the housing of each electric motor there must be a nameplate in accordance with GOST 12969 and GOST 12971 indicating the type, serial number of the machine, trademark, nominal and other technical data.

1.2. An emergency shutdown button should be located near the installation site of electric motors with remote or automatic control. The emergency button may only be used to stop the electric motor in an emergency. Emergency shutdown buttons must be protected from accidental or erroneous operation and sealed. Monitoring the safety of seals should be carried out by the personnel on duty in the electrical workshop.

1.3. Electric motors with dual control (local and remote from the operator station of the automated process control system) must be equipped with a switch for selecting the type of control, located at the local push-button control station, and an alarm for the switch position.

1.4. The degree of protection of protected electric motors intended for operation in enclosed spaces without artificial regulation of climatic conditions with dust content in the ambient air up to 2 mg/m 3 must be no lower than IP23 according to GOST 17494.

The degree of protection of electric motors of a closed, ventilated design, intended for operation outdoors and in rooms with high humidity and dust content of the ambient air of no more than 10 mU/m 3, must be no lower than IP44 according to GOST 17494.

The degree of protection of the output device for both versions of electric motors must be at least IP54.

Motors and their output devices intended for installation in rooms with high dust levels that require periodic water cleaning must have a degree of protection of at least IP55.

1.5. Exposed rotating parts (couplings, pulleys, shaft ends, belts and gears) must be guarded.

1.6. The motor housing and the metal sheath of the supply cable must be reliably grounded, ensuring a visible connection connection between the motor housing and the ground loop. The grounding conductor must be connected by welding to a metal base or by bolting to the motor frame.

1.7. For AC electric motors with a power over 100 kW, if it is necessary to control the technological process, as well as electric motors of mechanisms subject to technological overloads, stator current control must be ensured. The instrument scale is graduated in amperes for individual control and in percentage for a selective control system. The ammeter scale must have a line corresponding to the rated stator current.

On DC electric motors for driving fuel feeders, emergency oil pumps of turbines and shaft seals of hydrogen-cooled turbogenerators, regardless of their power, the armature current must be controlled. In cases where information on the MV unit is displayed on the video monitor of the operator station of the automated process control system, the indication of the current values of currents that exceed the rated value must differ from the indication of currents in the normal mode of the electric motor.

1.8. Switched-off electric motors that are on standby must always be ready for immediate starting. After starting the backup electric motor, it is necessary to inspect the electric motor and ensure its normal operation.

1.9. Electric motors that are in reserve must be put into operation, and those that are running must be transferred to reserve at least once a month according to a schedule approved by the technical manager of the power plant. In this case, for outdoor electric motors that do not have heating, the insulation resistance of the stator winding and the absorption coefficient must be checked.

Automatic transfer switching devices (ATDs) must be checked at least once a quarter according to the program and schedule approved by the technical manager of the power plant.

1.10. Ventilated electric motors installed in dusty rooms with high humidity and air temperature, must be equipped with devices for supplying clean cooling air.

The amount of air blown through the electric motor, as well as its parameters (temperature, impurity content, etc.) must comply with the instructions in the factory technical descriptions and operating instructions.

1.11. Air ducts for supplying and discharging cooling air must be made of non-combustible materials and have a mechanically strong and gas-tight design. Devices for regulating air flow and excess air pressure after final adjustment must be securely fastened and sealed. The tightness of the cooling path (air ducts, connections of air duct casings to the electric motor housing, dampers) must be checked at least once a year.

1.12. Individual external cooling fan motors should automatically turn on and off when the main motors are turned on and off.

1.13. The upper points of the water chambers of air coolers of electric motors must be equipped with taps to control the complete filling of the air coolers with water.

1.14. On electric motors with forced lubrication of bearings, protection must be installed that acts on the signal and shuts down the electric motor when the temperature of the bearing shells rises above the permissible level or when the flow stops. lubricants

1.15. On electric motors that have forced ventilation with separately installed fans, protection must be installed that acts on the signal and shuts down the electric motor when the motor temperature rises above the permissible control level. at certain points or when ventilation stops.

1.16. Electric motors AB (2AV)-8000/6000, which were previously used to drive power supply pumps with water cooling systems for the rotor winding and active stator steel, as well as electric motors with built-in water-air coolers, must be equipped with devices that signal the appearance of water in the housing. In addition, electric motors of the first group must be equipped with protection that acts on the signal when the condensate flow through the active parts decreases and turns off with a time delay of no more than 3 minutes when the circulation of the cooling medium stops.

The operation of equipment and equipment of water cooling systems, the quality of condensate in these systems and the cooling water of air coolers must comply with the instructions of the factory instructions.

1.17. To blow electric motors with compressed air during repairs, use air at a pressure of no more than 0.2 MPa (2 kgf/cm2). The air must be clean, free of moisture and oil. If possible, blowing should be done outdoors or in a special blowing chamber, or dust should be removed with a vacuum cleaner.

1.18. For installation, disassembly and assembly of electric motors, stationary, mobile or inventory lifting and transport devices must be provided.

1.19. Spare parts for electric motors should be stored at the power plant or repair facility and replenished as they are used.

1.20. For each electric motor with a power of 1 kW and above, regardless of operating voltage, there must be the following technical documentation:

Electric motor passport;

Acceptance test protocol;

Winding connection diagrams (if they are not standard);

Schematic and installation (executive) diagrams of control, alarm and relay protection. If the electric motors are of the same type, it is allowed to have the indicated diagrams in the documentation of one of the electric motors;

Technical reports on damage to electric motors;

Operation log,

1.21. Operational information on the electric motor is entered into a journal (form) by a senior foreman or foreman.

2 Operating conditions and permissible operating modes of electric motors

2.1. To ensure normal operation of electric motors, the voltage on the auxiliary buses must be maintained at 100-105% of the nominal value. If necessary, it is allowed to operate electric motors while maintaining their rated power in case of voltage deviations in the network up to ±10% of the rated value. Monitoring of the voltage level on the auxiliary buses should be carried out using measuring instruments (according to indications on the monitors of the automated process control system) installed on control panels (control room, main control room), as well as devices connected to voltage transformers or directly to the buses of sections and power assemblies in switchgear rooms , RUSN, etc.

2.2. When the frequency of the supply network changes within ±2.5% (1.25Hz) of the rated value, the electric motor is allowed to operate with the rated load.

2.3. The rated power of electric motors must be maintained with a simultaneous deviation of voltage up to ±10% and frequency up to ±2.5% (±1.25 Hz) of the rated values, provided that when working with increased voltage and reduced frequency or with reduced voltage and increased frequency, the sum of the absolute voltage and frequency deviations do not exceed 10%.

2.4. The voltage on the DC buses supplying power cabinets of electric motors, control circuits, relay protection devices, alarms and automation under normal operating conditions can be maintained 5% higher than the rated voltage of electrical receivers,

2.5. Electric motors must allow direct starting from full mains voltage and ensure that the mechanism starts both at full mains voltage and at a voltage of at least 80% of the rated voltage during the starting process. The values of the moments of resistance on the motor shaft during starts, as well as the permissible moments of inertia of the driven mechanisms, must be established in the technical specifications for motors of specific types.

2.6. Two-speed electric motors, as a rule, allow direct starting only from a lower-speed winding, followed by switching (if necessary) to a higher-speed winding.

The admissibility of direct starting from a winding of higher rotation speed and the number of such starts are determined by the technical conditions for a specific type of electric motor.

Switching of such motors should be done with no more than two switches.

Simultaneous activation of both windings is not allowed.

The completion of installation and commissioning work must be recorded by the responsible persons of the installation and commissioning organizations in the “Equipment entry log from installation”, stored on the central control panel.

4.2. During installation and adjustment, as well as upon completion, the electrical part of the mounted electric motor must undergo unit testing and acceptance by the foreman of the corresponding repair department or ETL group. The completion of unit-by-unit acceptance is recorded in the “Equipment Entry from Installation Log”, after which a test run is allowed.

4.3. Readiness for a test run is determined by the management of the electrical shop, based on the condition of the electric motor and the results of unit acceptance. At his request, the shift supervisor of the electrical shop instructs subordinate personnel to assemble the electrical circuit of the electric motor being tested. Before this, the personnel on duty in the electrical and technological shops must inspect the electric motor to the extent specified in the paragraphs and these Instructions.

4.4. A test run of the electric motor must be carried out in the presence of a foreman (engineer) of the electrical workshop, a representative of the installation organization, a foreman and a representative of the technological workshop. A test run is carried out to determine the direction of rotation (for two-speed electric motors, the direction of rotation is checked at both speeds), mechanical serviceability, and correct assembly and installation. A test run, as a rule, is carried out with the drive mechanism disconnected and not until it is fully turned. After short-term test starts and elimination of noticed defects, the electric motor is started idle for the time necessary for the bearings to reach a steady temperature. In this case, the vibration state, no-load current, bearing operation, and the absence of extraneous sounds must be checked.

4.5. The conduct and results of the trial launch must be noted by the launch manager in the “Equipment Entry from Installation Log” and by the duty personnel in the operational logs. Subsequent startups and assemblies of the electrical circuit can be carried out at the request of installation, commissioning and operational personnel through the shift supervisor of the technological workshop.

4.6. The electric motor is accepted for operation upon satisfactory results of comprehensive testing, after which the electric motor is transferred for service to operating personnel with an entry in the “Equipment Commissioning Log from Installation”.

4.7. Testing and running-in of electric motors after major and current repairs is carried out by installation personnel after making entries about the completion of repair work in the “Log of equipment input/output for repair.”

4.8. When preparing the electric motor for start-up (for the first time or after repair), the on-duty personnel of the technological workshop must check the following:

4.8.1. Completion of all work on the mechanism, closing of orders, absence of people and foreign objects on the unit and inside the fences.

4.8.2. Availability oil in oil pans and its level according oil indicator in electric motors with plain bearings and annular lubricant. In electric motors with forced lubrication, readiness for operation oil systems.

4.8.3. Presence of pressure And flow of water through air coolers (and oil coolers when their availability).

4.8.4. Shut-off position and control valves mechanisms taking into account the instructions point .

4.8.5.Sensor serviceability alarm devices and technological protections, thermal control devices and technological control(if available).

4.8.6. Reliability mounting the electric motor and mechanisms, the presence of protective guards for rotating parts and mechanical gears, no clutter service sites, availability markings on the electric motor.

4.8.7. On electric motors AB (2AV)-8000/6000, equipped with direct water cooling systems for the stator core and rotor winding, as well as units with a forced lubrication system for motor and mechanism bearings, prepare for start-up and put these systems into operation, ensuring that upon completion of repairs (installation) ):

Flushing of pipelines and circuit elements with condensate (oil) in addition to the active parts of the electric motor (bearings);

Filling the systems with clean condensate (oil) and checking that there is no airing of the hydraulic circuit elements;

Alternate short-term testing of pumps while idling and checking their performance;

Turning on the circulation of condensate (oil) through the active parts of the electric motor (unit bearings) with checking the density of the check valves of the pumps and adjusting the flow rate, pressure and temperature of the working medium within the required limits;

Testing (with the involvement of the on-duty personnel of the electrical shop and CTAI) of ATS pumps, process alarm devices, interlocks and protections, putting them into operation;

Inspect the systems included in the operation to ensure there are no leaks.

4.8.8. The mechanism is ready to start.

4.9. If there are no comments on the condition of the unit, the power plant shift supervisor must give a command to the electrical department shift supervisor to assemble the electrical circuit of the electric motor. Upon receipt of such an order, the electrical shop personnel on duty must:

4.9.1. Check the completion of work and closure of all issued work orders for work on the electric motor and its electrical equipment. Make sure there is an extract in the “Log of equipment input/output for repair.”

4.9.2. Inspect the electric motor and its electrical equipment; check the connection of the power cables to the motor terminals, the absence of bare live parts, the tightness of the output device or the closure of the terminal chamber, the serviceability of the starting and switching equipment, the condition of the brush device, the presence and serviceability of the protective grounding of the electric motor.

4.9.3. Make sure that the area around the electric motor and the electric motor itself are clear of dirt and foreign objects.

4.9.4. Remove portable grounding connections or disconnect the grounding blades.

4.9.5. Using a megohmmeter, check the integrity of the phases of the stator winding and the supply cable and the condition of the insulation windings, which must comply with the following.

For new electric power units put into operation for the first time motors and electric motors, who have undergone rehabilitation or major repairs and reconstruction at a specialized repair shop enterprise, acceptable values insulation resistance winding st ator, absorption coefficient and nonlinearity coefficient, being the conditions of their inclusions in work without drying are given in tables 5 and 6.

Rotor winding insulation resistancesynchronous electric motors and asynchronous electric motors with a wound rotor for voltage 3 kV and higher or power more than 1 MW, switched on for the first time into operation, it must be at least 0.2 MOhm, and after completion of scheduled repairs it is not standardized.

For electric motorsvoltage above 1 kV in operation, the permissible value of the insulation resistance of the stator winding R 60 and absorption coefficient at the end of capital or no current repairs are standardized, but must be taken into account when deciding whether to dry them. In operation, determination of the absorption coefficient is mandatory for electric motors with voltages above 3 kV or power more than 1 MW. It should be taken into account that when the engine is under repair for a long time, its stator winding may become moist, which may require drying and for this reason delay its commissioning. Therefore, when starting a unit from scheduled repairs, measuring Insulation of the stator winding of electric motors of critical auxiliary mechanisms should be carried out no later than 2 days. before the scheduled completion date of the repair. The insulation resistance of the stator windings of electric motors with voltages above 1 kV, together with the supply cable, which are started up after a long period of inactivity or being in reserve, is also not standardized. It is considered sufficient if the specified resistance is at least 1 MΩ per 1 kV of rated line voltage. Insulation resistance is measured at a rated winding voltage of up to 0.5 kV inclusive with a mega-ohmmeter for a voltage of 500 V, for a rated winding voltage of over 0.5 kV to 1 kV - with a mega-ohmmeter for a voltage of 1000 V, and for a winding voltage above 1 kV - with a mega-ohmmeter for a voltage of 2500 V.

Table5

Acceptable values of insulation resistance, absorption coefficients and nonlinearity for stator windings, new electric motors put into operation for the first time and electric motors that have undergone restoration or major repairs and reconstruction at a specialized repair enterprise

Power, rated voltage of the electric motor, type of winding insulation

Criteria for assessing the state of stator winding insulation

Insulation resistance value, MOhm

Absorption coefficient value R 60 ² / R 15 ²

Coefficient value nonlinearity ** K u = I nb × U nm / I nm × U nb

1. Power over 5MW, thermoset and mica compound insulation

Not lower than 10MΩ per 1kV rated line voltage at temperature* 10-30°C

No more than 3

2. Power 5 MW and below, voltage above 1kb, thermosetting insulation

Not lower than 10MΩ per 1kV rated line voltage at temperature* 10-30°C

Not less than 1.3 at temperature* 10-30°C

3. Electric motors with mica compound insulation, voltage over 1 kV, power from 1 to 5 MW inclusive, as well as motors of lower power for outdoor installation with the same insulation with voltage over 1 kV

Not lower than 1.2

4 . Electric motors with mycalentcompounded insulation, voltage over 1 kV. power less than 1 MW, except as specified in paragraph 3

Not lower than the values indicated in table 6

Not lower than 1Mohm at a temperature* 10-30°C

* At temperatures above 30°C the permissible insulation resistance value is reduced

2 times for every 20°C difference between the temperature at which the measurement is performed and 30°C,

** U nb - the greatest, i.e., the full test rectified voltage (voltage of the last stage); U nm - the lowest test voltage in rectified (first stage voltage); I nb and I nm - leakage currents (I 60 ² ) at voltages U nb and U nm.

To avoid local overheating of the insulation by leakage currents, voltage withholding at the next stage is allowed only if the leakage currents do not exceed the values indicated below:

Multiplicity of test voltage in relation to U nom			1.5 and above
Leakage current, µA			1000

Table 6

The lowest permissible values of insulation resistance for electric motors (see table 5, points 3 and 4)

Winding temperature,°C	Insulation resistance R 60 ² , MOhm at rated winding voltage, kV
Winding temperature,°C	3-3,15	6-6,3	10-10,5

In case of an unacceptable decrease in insulation resistance and unsatisfactory values of the absorption coefficient and non-linearity, the electric motor must be dried.

4.9.6. Remove safety signs and prohibition warning posters from the electric motor and switching equipment, which was used to disassemble the electrical circuit of the electric motor.

4.9.7. Assemble the electrical circuit of the electric motor and lubrication oil pumps (if any), apply operational current to the control, protection, alarm circuits, automation and interlock circuits. In preparation for operation of electric motors of ball mills, in addition to assembly electrical diagram synchronous motors and their oil station, it is necessary to assemble electrical circuits of their exciters (excitation systems) and fans of the forced cooling system (if the latter are present).

4.9.8. Check the presence and operation of signal lamps on the control panel, the absence of dropped indicator relays and signals about a malfunction of the circuit and electrical engine, including information about unavailability displayed on the monitor of the automated process control system (if available).

4.9.9. Report to the person who gave the order to prepare the electric motor for start-up about assembling the electrical circuit And motor readiness to switch onto the network. Make an entry in the operational log.

5.1. The electric motor is switched on by the duty personnel of the technological workshop servicing this mechanism. About the upcoming launch of a powerful or the responsible electric motor located in long-term reserve(more than 1 month) or after repair, the workshop personnel servicing the starting mechanism must notify the electrical workshop personnel, who are obliged to perform pre-starting operations in accordance with clause 4.9. The exceptions are launches related to the elimination of an emergency situation, and launches electric motors, switched on by AVR.

5.2. When turning on the electric motor locally, its control key (button) should be kept in the “On” position until the electric motor turns.

When turning on the electric motor remotely, its control key (virtual key on the video frame of the technological diagram of the unit being started) should be kept in the “On” position until the alarm goes off, indicating the end of the operation (signal lamp, light display, etc. comes on).

5.3. At the location where the electric motor is installed, it is necessary to monitor the starting mode. The supervisor of the technological workshop must check the correct rotation, ease of movement, and the absence of extraneous noise. In the event of sparks, smoke from the winding or bearings, extraneous sound, knocking and rubbing, you should immediately turn off the electric motor with the emergency button.

During a normal start-up, the observer must inspect the electric motor, make sure that the bearings are operating normally and that there is no unacceptable heating or vibration.

5.4. The person performing the start must monitor the start using an ammeter or stator current indication on the screen of the operator station of the automated process control system (if available).

When starting an asynchronous electric motor with a squirrel-cage rotor, the stator current exceeds the rated value by 5-7 times and remains practically unchanged throughout the entire start-up. As soon as the rotor speed reaches 90% of the rated value, the stator current decreases sharply to a value close to the rated value or lower. The start-up time, depending on the flywheel masses of the unit, ranges from several seconds (circulation, feed pumps) to tens of seconds (blown fans, smoke exhausters).

When starting a synchronous motor of a ball mill, it is initially started asynchronously due to the starting short-circuited winding located in the pole pieces. Upon reaching a subsynchronous rotation speed, the motor is automatically excited by supplying direct current to the circuit of the working rotor winding, and the electric motor is pulled into synchronism. Signs of involvement engine deceleration synchronism is determined by the presence of excitation current and the steady position of the ammeter needle in the stator winding circuit.

If the stator current at the end of the start exceeds the rated value, it is necessary to partially unload the motor in terms of active power and, if necessary, reactive power (the latter only for synchronous motors when operating with a reduced (advanced) power factor).

5.5. If, at the moment of turning on the electric motor with a voltage above 1000V, the signal “Ground on the section...” appears, the electric motor should be turned off and the duty personnel of the electrical workshop should be informed about this.

5.6. If the engine turns off during start-up, it is necessary to acknowledge the control key, inspect the electric motor and inform the electrical shop personnel on duty to take measures to determine the cause of the shutdown and activation of the protection.

5.7. Two-speed motors, as a rule, should be connected to the network on a winding of lower rotation speed with subsequent switching (if necessary) to a winding of higher rotation speed.

The admissibility of direct starting from a winding of higher rotation speed and the number of such starts are determined by technical conditions or factory operating instructions for specific motors.

Simultaneous activation of both windings is not allowed.

5.8. Starting electric motors that drive fans (smoke exhausters, blower fans, hot blast fans, etc.) must be started with the dampers closed.

5.9. Electric motors with squirrel-cage rotors are allowed, according to the conditions of their heating, to be started from a cold state 2 times in a row, from a hot state - 1 time, if the factory instructions do not allow more starts. Subsequent starts are allowed after the electric motor has cooled for a time determined by the factory instructions.

Subsequent starts of electric motors with voltages over 1000V are allowed after 3 hours.

6 Supervision of electric motor operation

6.1. Constant supervision of the operation of electric motors must be carried out by the on-duty personnel of the technological workshop servicing the mechanisms. In addition, the condition and operating mode of electric motors must be monitored by the personnel on duty in the electrical workshop through periodic scheduled walk-throughs and inspections of all electric motors, both working and in reserve. Regardless of this, all electric motors with voltages above 1000V at least 2 times a month, and the rest must be inspected by a repairman once a month.

Extraordinary inspections of electric motors must be carried out when their protection is switched off and there is a sudden change in climatic conditions (for outdoor units) and operating mode.

6.2. Electric motors that have been in reserve for a long time and automatic reserve switching devices must be inspected and tested together with the mechanisms according to a schedule approved by the technical manager of the power plant, but at least once a month.

6.3. During operation of the electric motor, the personnel on duty in technological workshops are obliged to:

6.3.1. Regulate the load of electric motors within acceptable limits depending on the operating mode of the boiler, turbine and other equipment of the power plant, ensuring that the stator (rotor) currents do not exceed the rated values. If there are no ammeters, monitor the heating temperature electric motor directly touching the body with your hand. If the permissible limits for current or heating are exceeded, it is necessary to unload the unit and take measures to determine the cause of the overload.

6.3.2. Monitor heating and vibration of bearings. If an increase in temperature or vibration of the bearing is detected by touch, it is necessary carry out a control measurement through a portable device (with lack of stationary devices).

Extremely valid values vibration and temperature electric motor bearings are given in paragraphs and.

6.3.3. Check the oil level in electric motors with ring-lubricated bearings. Sleeve bearing chambers must be filled out oil up to the mark on the oil level gauge or, if there is no mark, to the middle of the oil indicator glass on bearing. If necessary, add oil recommended by the manufacturer brands (T22, T30, Tp30 or other). Frequent topping up (more than once a month) with indicates its leak. Especially oil leakage inside the housing is dangerous electric motor, because the it may cause corrosion covers, varnishes and reducing the insulation resistance of the stator winding.

IN electric motors with using a forced lubrication system, control the oil pressure in the oil pressure pipe and the amount of oil at the bearing drain, which should fill approximately 1/2 to 1/3 of the cross-section of the oil drain pipe.

6.3.4. Ensure proper operation of the lubricating rings, in particular their rotation. Rapid rotation of the lubrication rings, accompanied by a slight ringing sound, indicates a lack of oil in the bearing chamber.

6.3.5. Pay attention to the appearance of abnormal noise in the rolling bearings, indicating an insufficient amount of lubrication or the appearance of a defect on the surfaces of the races and rolling elements, and report this to the shift supervisor of the electrical department.

6.3.6. Monitor stator heating using standard heat control sensors. If increased heating of the winding, core and cooling air is detected, partially unload the motor along the stator (rotor) currents and take immediate measures to restore the normal thermal state of the electric motor by adjusting the parameters of the cooling water and condensate used to cool the rotor and stator core.

If it is impossible to reduce temperatures to acceptable values, the engine must be stopped in agreement with the shift supervisor of the electrical department.

6.3.7. Observe the brush apparatus of synchronous electric motors. If unacceptable sparking, increased vibration and other defects are detected, report this to the shift supervisor of the electrical department so that measures can be taken to normalize the operation of the current collection unit.

6.3.8. Monitor the operating mode of air coolers, as well as the direct water cooling system of electric motors AB (2AV)-8000/6000, ensuring that the pressures, flow rates and temperatures of cooling water and condensate are maintained within acceptable limits.

6.3.9. Make sure that all rotating parts of the electric motor (shaft ends, coupling halves, pulleys, etc.) are securely covered with guards.

6.3.10. Do not allow steam, water or oil to enter the motor output device or inside its housing.

6.3.12. Keep records of electric motor starts and stops.

6.3.13. Notify the shift supervisor of the electrical shop about any abnormalities in the operation of the electric motor.

6.4. When walking around and inspecting an electric motor, the personnel on duty in the electrical shop must monitor:

Load, housing heating, temperature of the cooling medium, rolling bearings, copper and stator core (without the right to regulate them);

Vibration of bearings and housing (to the touch);

No leaks from air coolers built into the stator and water supply units to the active parts of the electric motor inside their housings;

Condition of lighting of the service area;

Condition of grounding of the electric motor housing;

Terminal box condition;

No heating of contact connections and no smell of burnt insulation;

The condition of the brush-contact devices of alternating current electric motors (the degree of sparking, heating and vibration of the electric brushes, the force of pressing the brushes to the slip rings, the contamination of the device with brush dust, the presence of stuck, extremely worn brushes, as well as brushes with mechanical damage to their fittings, etc. are monitored. ).

6.5. If during inspections emergency situations and malfunctions in the operation of electric motors are identified, it is necessary to eliminate them, provided that the operations carried out in this case are allowed to be carried out by production instructions and safety rules solely by the person on duty. Otherwise, it is necessary to immediately inform a higher operational person about the emergency condition and the need to take urgent action.

A list of the most common malfunctions of electric motors and methods for eliminating them are given in the appendix to this Instruction.

6.6. The electrical shop staff on duty can switch off the electric motor or change its operating mode only with the permission of the shift supervisor of the workshop where the electric motor is installed, with the exception of emergency cases (see Section 7).

6.7. All work related to the repair of electric motors is carried out by repair personnel of the electrical shop or a specialized repair organization.

Urgent work to eliminate electric motor malfunctions that threaten to disrupt the normal operation of the unit (station) is allowed to be carried out by the personnel on duty. In this case, before work, all organizational and technical measures to prepare the workplace must be completed.

7 Emergency shutdown of the electric motor

7.1 The electric motor must be immediately (emergency) disconnected from the network under the following circumstances:

Accidents with people;

The appearance of smoke or fire from the housing (output device), bearings, oil pipes of the electric motor, its starting and exciting devices;

Fire in oil pipelines and the impossibility of extinguishing it;

Breakage of the driven mechanism;

Failure of technological protections to stop the supply of condensate to the rotor and stator core of electric motors AB (2AV)-8000/6000 and an unacceptable decrease in pressure in the bearing lubrication system.

After an emergency shutdown of a running electric motor, measures must be taken to turn on the backup unit and the shift supervisor of the technological workshop and the shift supervisor of the electrical workshop must be notified.

7.2 The electric motor must be stopped after starting the electric motor of the standby unit (if available) or after warning the technological shift supervisor in the following cases:

The appearance of abnormal noise in the electric motor;

The smell of burnt insulation appears;

A sharp increase in vibration of the electric motor or the mechanism driven by it;

Unacceptable increase in bearing temperature;

Electric motor overload above permissible limits;

Electric motor operation in two phases;

There is a threat of damage to the electric motor (flooding with water, steaming, etc.).

8 Action of personnel during automatic shutdown of the electric motor by protections

8.1. During operation of the electric motor, it is possible that it will be automatically disconnected from the network by technological or electrical protection.

When a running electric motor is automatically switched off, the personnel on duty in the process shop must immediately check the successful activation of the backup unit from the ATS. If the ATS fails or is absent, it is necessary to turn on the electric motor of the backup unit by hand, notifying the shift supervisor of the workshop in which the electric motor is installed and the shift supervisor of the electrical workshop.

After turning on the electric motor of the standby unit, the personnel on duty in the electrical shop must, on the switched-off electric motor:

Check for the absence of signs leading to an emergency shutdown and indicated in;

Find out the reason for the shutdown using the indicator relays and the corresponding alarm system;

Carry out an external inspection of the switched-off electric motor in order to look for obvious signs of a short circuit;

Using a megohmmeter, check the insulation condition of the stator winding and power cable.

The duty personnel of the technological workshop must:

Check the operation of the switched-on electric motor;

Observe the switched-on electric motor for 1 hour;

Record the observation results in the operational journal.

8.2. Restarting electric motors in the event of their shutdown by the main protections is permitted after inspection and control measurements of insulation resistance. If signs of damage to the electric motor or cable are detected, its electrical circuit must be disassembled and the shift supervisor of the technological workshop, as well as the supervisor of the electrical workshop, must be informed to take measures to replace the damaged electric motor or carry out emergency repairs.

8.3. An emergency shutdown of an electric motor with overload protection without signs of a short circuit is possible due to jamming, jamming and other malfunctions of the mechanism. This can be established by measuring the stator current when testing the electric motor under load and at idle without a mechanism (with the coupling halves disengaged). In this case, the electric motor can be put into operation only after the process shop personnel have eliminated the cause of the overload and mechanism malfunction.

8.4. If the electric motor of a critical mechanism is disconnected from the protection action and there is no backup electric motor, it is allowed to restart the electric motor after an external inspection and obtaining permission from the shift supervisor of the electrical shop and the station shift supervisor with registration of all instructions and operations in the operational log.

The list of critical mechanisms that are subject to the requirements of this paragraph must be approved by the technical manager of the power plant and indicated in the local operating instructions for electric motors.

8.5. Restarting electric motors in cases of backup protection until the cause of the shutdown is determined is not allowed.

8.6. In the event of an emergency shutdown of the electric motor as a result of a short circuit in the winding or at its terminals, it may catch fire. Extinguishing an electric motor fire should be carried out after disassembling the electrical circuit with a carbon dioxide fire extinguisher or water. It is prohibited to extinguish a burning electric motor with a foam fire extinguisher and sand.

9 Taking the electric motor out for repair

9.1. No repair work is allowed on a rotating electric motor, except for those that do not involve approaching live and rotating parts (cleaning, marking, painting, repairing bases and foundations).

9.2. Switching off the electric motor for repairs is carried out by the duty personnel of the technological workshop at the direction of the workshop shift supervisor with the permission of the station shift supervisor on the basis of an existing application.

During a planned shutdown of the electric motor, the load is reduced taking into account the instructions in paragraph , the electric motor switch is turned off, the excitation is turned off (for synchronous electric motors), the oil pumps of the forced lubrication system are turned off (after the rotor has stopped rotating), the water cooling pumps of the active parts of the engines are turned off, water is removed and the cooling system is dried compressed air (for electric motors type AB (2AV)-8000/6000), stopping the supply of cooling water to the air cooler and disassembling the electrical circuits of the electric motor itself and the electric motors of its supporting systems.

During long shutdowns or breaks in work, if the ambient temperature is below 5ºC, electric heaters on outdoor electric motors must be turned on, if they are provided by the manufacturer.

9.3. An entry must be made in the operational log of the duty personnel about for what work, in what workshop and at whose request the electric motor was stopped.

9.4. After the electric motor is turned off, the on-duty personnel of the technological workshop must post a prohibiting poster “Do not turn on!” on the key or control button of the stopped electric motor. People are working." In addition, measures must be taken to prevent the rotation of the electric motor from the mechanism side. Such measures are closing the pressure valve, guide vanes, gates, and tying the steering wheels with a chain and locking them, hanging a prohibitory poster “Do not open! People are working."

9.5. Until the completion of the repair work and until the closure of the work order, the personnel on duty in the process shop do not have the right to remove these prohibitory posters. They must be removed before assembling the electric motor circuit as directed by the workshop shift supervisor.

9.6. To carry out repair work on the rotating parts of a mechanism or electric motor or on its live parts, the on-duty personnel of the electrical workshop, at the direction of the shift supervisor of the electrical workshop or at the request of the station shift supervisor, must take the following measures to prepare the workplace.

9.6.1. The electrical circuit of an electric motor with a voltage above 1 kV must be disassembled, creating a visible break by rolling out the switchgear trolley into the repair position. The protective curtains must be locked and a prohibitory sign “Do not turn on!” must be posted on them. People are working." A grounding blade must be included in the switchgear cell.

For a two-speed electric motor, both power circuits of the stator windings must be disconnected and disassembled.

9.6.2. The electrical circuit of electric motors with a voltage of 380V connected to the RUSN-0.4 kV section must be disassembled by turning off the circuit breaker and installing its trolley in the repair position. A prohibitory poster “Do not turn on!” must be posted. People are working,” the power cable was disconnected from the motor terminals and a portable grounding connection was installed.

9.6.3. The electrical circuit of 380V electric motors connected to power assemblies must be disassembled by turning off the circuit breaker; a poster “Do not turn on!” must be hung on its handle. People are working." On live parts after the circuit breaker, the absence of voltage must be checked and the grounding blade must be turned on, and if it is absent, the power cable must be disconnected from the motor terminals and a portable grounding must be installed.

For electric motors of small power, in which the cross-section of the supply cable does not allow installing portable grounding, it is allowed to ground the cable (with or without disconnecting from the electric motor terminals) with a copper conductor with a cross-section not less than the cross-section of the cable core or connect the cable cores together and insulate them. In this case, twists are allowed.

9.7. Upon completion of the preparation of workplaces, the operational log of the shift manager of the electrical workshop should record at whose instructions, the application of which workshop and for what work the electric motor was taken out for repair.

9.8. If the power cable of the electric motor of the mechanism being repaired is grounded on the side of the cell or assembly, then disconnecting the cable from the terminals of the electric motor (at the request of the technological workshop) should be performed only in cases where during the repair it is necessary to move, rotate or remove the electric motor from the foundation.

As a rule, disconnecting cables from the terminals of electric motors should be done when the unit or other technological equipment is taken out for major repairs.

9.9. When stopping the mechanism only for repairing the electric motor, disconnecting the cable from the motor terminals, if grounding is installed on the RUSN side, must be carried out by personnel repairing the electric motor.

9.10. In all cases, portable grounding must be installed at the disconnected ends of the cable by the electrical shop personnel on duty.

9.11. Upon completion of the repair, the connection of the power cable to the motor terminals should usually be carried out by the personnel repairing the motor. As an exception, in emergency cases, the cable connection is allowed to be made by the personnel on duty.

9.12. Repair work on electric motors located on the territory of the technological workshop is carried out according to orders and orders issued by the electrical workshop on a daily basis. the decision of the shift manager of the technological workshop, who must record this in his operational log. The permission must be transferred by telephone to the electrical shop personnel on duty (permitting) and recorded in its operational log.

9.13. During major and current repairs of the unit, permission to work on electric motors located in the premises of the technological workshop and located within the coverage area of the general order must be carried out in accordance with orders and orders endorsed by the responsible manager for the general order.

In this case, permission for daily access from the shift supervisor of the technological workshop is not required. Permission to work is carried out by the personnel on duty in the electrical workshop. The provision of work orders and orders for approval to the responsible manager for the general work order should be done by the work manager for the work order for repairing the electric motor.

9.14. Testing of control circuits, protection devices and technological interlocks acting on the electric motor switch is allowed to be carried out on the unit being repaired (with a valid general order) provided that the switchgear trolley is installed in the test position and there is grounding in the switchgear cell.

9.15. The testing must be carried out at the request of the personnel of the ETL or the thermal automation shop with the permission of the shift supervisor of the technological workshop after confirmation by the shift supervisor of the electrical workshop that the above test conditions have been met.

9.16. Testing of technological protections and interlocks should be carried out with a minimum number of operations with switching equipment (to reduce wear, preserve the settings of the switch and contact block).

9.17. The assembly of the circuit for testing the electric motor is carried out by the personnel on duty in the electrical workshop at the request of the work manager with the permission of the shift supervisor of the technological workshop.

9.18. The switching on of the tested electric motor is carried out by the personnel on duty of the technological workshop at the direction of the shift supervisor of the technological workshop and at the command of the work manager conducting the testing.

During testing, a prohibitory sign “Do not turn on! People are working” is removed from the switch control key and installed again after testing.

10 Maintenance, scope of repairs and testing of electric motors.

10.1. Maintenance and repair involve the implementation of a set of works aimed at ensuring the good condition of electric motors, their reliable, safe and economical operation, carried out with a certain frequency and sequence at optimal labor and material costs.

10.2. Maintenance that does not require taking electric motors out for routine repairs includes:

Scheduled walk-throughs and technical inspection of operating electric motors;

Monitoring the technical condition of electric motors using external monitoring or diagnostic tools, including monitoring with portable equipment;

Replenishing and replacing lubricant of rubbing parts, cleaning oil and water filters, tightening oil seals, checking control mechanisms, etc.;

Elimination of water, oil leaks and other individual defects identified during condition monitoring and performance testing;

Adjustment and purging of the brush apparatus of synchronous electric motors;

Inspection and testing of electric motors when they are in reserve or on conservation in order to identify and eliminate deviations from the normal state;

Monitoring the serviceability of measuring systems and measuring instruments, including their calibration and other work to maintain the good condition of electric motors;

10.3. At each power plant:

The scope of engine maintenance work and the frequency (schedule) of their implementation are established for each group of mechanisms, taking into account the requirements of the manufacturer and operating conditions;

Responsible performers of maintenance work are appointed or an agreement is concluded with a contractor to perform these works;

A control system is being introduced to monitor the timely completion and scope of work during maintenance;

Maintenance logs (operational logs) are drawn up, in which information about the work performed, deadlines and performers must be entered.

10.4. The frequency and scope of maintenance of electric motors and spare parts for them stored at the power plant are established by power plants in accordance with the instructions for the storage and preservation of engines and spare parts for them.

10.5. The type of repair of electric motors is determined by the type of repair of the main equipment, but may differ from it and be determined by the power plant based on local conditions.

10.6. Overhaul of electric motors, as a rule, is carried out simultaneously with repair of the mechanism. Combining the timing of repairs of electric motors with mechanisms is advisable in order to reduce labor costs for work related to alignment, preparation of the unit’s workplace, etc.

If, due to its technical condition, the electric motor cannot ensure reliable operation until the next major overhaul of the technological unit, then the malfunction must be eliminated during the current repair.

When planning the timing of major and current repairs, it is necessary to take into account the technical condition of electric motors established during operation (heating of active parts, vibration, condition of bearings, etc.).

10.7. The schedules and scope of repairs are approved by the technical manager of the power plant and are mandatory for repair personnel. When repairs of electric motors are carried out by a contracting organization, schedules and volumes are additionally coordinated with the latter’s management.

10.8. Before the electric motor is taken out for repair, all preparatory work must be completed:

Long-term and annual plans for preparation for repairs have been developed;

A statement of planned work on the repair of electric motors provided for in the annual plan has been prepared;

Technical documentation for modernization or reconstruction work was compiled and approved;

The necessary materials, tools and equipment have been prepared;

Lifting mechanisms and rigging devices were brought into compliance with the rules of Gosgortekhnadzor;

The necessary spare parts have been prepared;

Fire and safety measures have been completed.

10.9. The start of repair of the electric motor is considered to be the time of withdrawal for repair, established by the shift supervisor of the power plant,

10.10. Before stopping the electric motor for repairs while it is operating under load, operational measurements of electric motor parameters are carried out and an assessment of the current condition of the engine and its supporting systems is carried out, which are entered into the list of the main parameters of the technical condition of the electric motor, and equipment and service areas are also cleaned.

10.11. During routine repairs, the following work is performed:

Cleaning and blowing with compressed air;

Checking the air gaps between the stator and rotor;

Measuring clearances in plain bearings;

Inspection of the terminal box and contact connections;

Inspection of the bearing assembly, replacement or addition of: strokes.

10.12. The scope of overhaul of an electric motor according to the standard nomenclature includes the following work:

10.12.1. DC motors:

Pre-repair measurements and tests , defective assembly;

Dismantling from the installation site and transportation to the workshop;

Examination air gaps between the armature and the poles;

Disassembly electric motor;

Cleaning and blowing with compressed air, as well as using detergents;

Defect wrapped anchor;

Groove and continuation of the commutator, checking the quality of soldering of the armature winding to the commutator;

Defects of the traverse, revision of brush holders, replacement of electric brushes;

Defects of the magnetic system and repair of coils of the main and additional poles;

Defects of the frame and bearing shields;

Inspection and replacement of rolling bearings;

Electric motor assembly;

On-site installation, alignment with mechanism;

Measurements and tests after repair.

10.12.2 Asynchronous and synchronous electric motors:

Pre-repair measurements and tests, assembly defect detection;

Dismantling from the installation site and transportation to the workshop;

Checking the air gaps between the armature and the rotor, in plain bearings;

Complete disassembly with rotor removal (on site or in the workshop);

Inspection and cleaning of all parts and components;

Checking the compaction density of the stator active steel;

Inspection of welds and fasteners;

Checking the fastening of the stator winding in the slot and end parts;

Inspection of connections, stator winding terminals and terminal box;

Checking the fastening of the active steel of the rotor, blades and fan hub;

Inspection of the squirrel cage, fans and rotor bandage units;

Checking the serviceability of the squirrel-cage rotor rods and their tight fit in the groove;

Checking the fastening of poles, pole windings and interpole connections of synchronous electric motors;

Checking the integrity of the damper (starting) winding;

Defects of slip rings with their grooving and grinding, checking the condition of traverses, brush holders, replacing defective and worn electric brushes;

Checking the fastening of balancing weights; replacement of lubricant and repair of bearings;

Defects and repairs of the thrust bearing (disassembling and cleaning the oil reservoir, removing segments and their supports; checking the condition of fasteners and welds, cups of support bolts of the stops of the segments; checking the condition of the mirror surface of the disk, the insulating gasket and the tightness of its fit on the thrust bearing bushing; checking the segments and their supports, scraping them onto the surface plate; installing segments and adjusting the load on the segments; replacing sealing elements, assembling the oil pan and sealing it);

Inspection of the cooling system (dismantling of the air cooler, oil cooler, their disassembly, cleaning and washing, replacement of gaskets and assembly; hydraulic tests and elimination of detected defects; installation of the oil cooler and its pressure testing with the system; inspection, high pressure water testing of the air cooler and heat exchanger of the water cooling system of the AB electric motor (2АВ)-8000/6000, carrying out hydraulic tests of the water supply units of the rotor winding and the stator core of these electric motors);

Stator painting;

Electric motor assembly;

Electrical measurements and tests after repair.

10.13. After stopping the electric motor for repairs, electrical shop personnel must:

Carry out all shutdowns to ensure safe working conditions;

Issue a work permit to repair the electric motor;

Establish the working hours of support workers (warehouses, laboratories, cranes, etc.).

10.14. During the repair process, the management personnel of the electrical shop must:

Carry out incoming quality control of used materials and spare parts;

Conduct operational quality control of repair work performed;

Check compliance with technological discipline (compliance with the requirements of technological documentation, the quality of the devices and tools used).

10.15. During a major overhaul of an electric motor, reconstruction of its components can be carried out in order to eliminate deficiencies identified during operation, as well as special work related to the repair or replacement of individual components. Changing the dimensions of parts, replacing components with products of a different type must be agreed with the electric motor manufacturer.

10.16. Special work related to the repair of the rotor and stator windings, their partial or complete replacement, the repair of rotor banding units and reconstruction, are usually carried out by a repair company.

10.17. Vibration measurements of the electric motor (bearings, stator and base plate) should be carried out in the vertical, transverse and axial directions after each scheduled repair, as well as after trimming the bearing shells or replacing them, correcting the alignment, or if obvious signs of increased vibration are detected.

10.18. High-voltage electric motors, as well as critical electric motors, regardless of voltage, after completion of installation or major repairs must be accepted by a commission headed by the management of the electrical shop with the execution of a bilateral act for each electric motor.

Acceptance of the electric motor is carried out partially in accordance with the repair technology - during the assembly process after repair work has been completed; in general - after assembly during testing under load.

10.19. Information about repairs must be included in the documentation of the electric motor no later than 10 days after completion of the repair.

10.20. The suitability of the electric motor for operation is determined on the basis of the results of tests carried out in accordance with the requirements of Chapters 4 and 5 of the current “Scope and Standards for Testing Electrical Equipment” and based on the totality of all tests and inspections performed.

11 Safety precautions when servicing electric motors. Fire safety.

11.1. The basis for the safe operation of electric motors is compliance with the requirements of the current PTE, PTB, PPB, factory instructions for specific types of machines, compliance with permissible operating conditions (in terms of load, heating, vibration, lubrication, etc.) and maintenance (inspections, repairs) , preventive tests).

11.2. Operational and maintenance of electric motors must be carried out by persons who have undergone training, instruction and special training in studying the principles of operation, design, layout and maintenance methods of electric motors, who have acquired skills and experience in practical work, who have passed exams on knowledge of the rules of technical operation, safety precautions, official and local operating instructions for the equipment assigned to them.

11.3. Repair and restoration work on a specific electric motor must be carried out, as a rule, with the unit stopped and a permit issued.

Admission of repair crews to the work site is carried out by the power plant personnel on duty.

11.4. The admission of crews to repair work on rotating and current-carrying parts of the electric motor must be carried out after performing technical measures, which are described in sufficient detail in Section 11.

11.5. The winding terminals and cable funnels of electric motors must be covered with guards, the removal of which requires unscrewing the nuts or unscrewing the bolts. It is not allowed to remove these guards while the electric motor is running.

11.6. Rotating parts of electric motors and parts connecting electric motors to mechanisms (clutches, pulleys) must be protected from accidental touches.

11.7. For a running two-speed motor, the unused stator winding and the cable supplying it must be considered live.

11.8. When working simultaneously on the mechanism and the electric motor, the coupling must be disengaged. The clutch must be disengaged by repair personnel in accordance with the repair order for the rotating mechanism.

11.9. Before starting work on an electric motor driving a pump or draft mechanism, measures must be taken to prevent rotation of the electric motor on the mechanism side. Such measures are closing the corresponding valves or gates, locking their steering wheels using chains or other devices and devices. Signs “Do not open!” must be posted on disconnected fittings and the starting device of the mechanism. People are working" and "Do not turn on! People are working”, prohibiting the supply of voltage and the operation of shut-off valves, and at the place of work there is a safety sign “Work here!”

11.10. Work on an electric motor (or group of electric motors), from which the power cable is disconnected and its ends are short-circuited and grounded, can be carried out without a work order, by order.

The supply of operating voltage to the electric motor until the work is completed (test start-up, testing of the electric motor or its starting device) can be done after the removal of the team, the return of the work order by the manufacturer to the operating personnel and the removal of temporary fences, locking devices and posters.

The work manager is obliged to warn his team about the supply of voltage.

Preparation of the workplace and admission of the team after trial activation is carried out as during the initial admission.

11.11. During the period of repair, it is prohibited to use fire-hazardous detergents to clean metal parts, assemblies and windings with thermosetting insulation from contamination.

11.12. It is prohibited to service electric motors in women's clothing, raincoats, coats and robes due to the possibility of getting caught in the rotating parts of said clothing.

11.13. Servicing the brush apparatus while the electric motor is running is permitted by order of an employee trained for this purpose with electrical safety group III, subject to the following precautions:

Work using face and eye protection, wearing protective clothing that is buttoned up, being careful not to get caught in the rotating parts of the electric motor;

Use dielectric galoshes and carpets;

Do not touch live parts of two poles or live and grounding parts with your hands at the same time.

Rotor rings can only be ground on a rotating electric motor using pads made of insulating material.

11.14. The use of rubber, polyethylene and other gaskets made of soft and non-oil-resistant material for flange connections of oil pipelines of the electric motor lubrication system is prohibited.

11.15. It is prohibited to carry out work on the oil pipelines and equipment of the oil system during its operation, with the exception of replacing pressure gauges and adding oil.

11.16. Fire extinguishing in electric motors (after de-energizing them) must be done with water, carbon dioxide or bromine ethyl fire extinguishers.

It is not allowed to extinguish fires in electric motors with foam fire extinguishers or sand.

11.17. If a winding fire is detected inside the motor housing, it must be disconnected from the network, and the excitation on the synchronous electric motor must be de-energized.

Personnel can extinguish a fire in an electric motor winding manually through special inspection and technological hatches using mobile fire extinguishing equipment (fire extinguishers, fire nozzles, etc.) after turning off the electric motor.

12 General instructions for drawing up local instructions.

12.1. Based on this Standard Instruction, local instructions must be drawn up at each power plant. In this case, the requirements and recommendations of manufacturers, industry normative documents must be fully taken into account, taking into account operating experience and test results, as well as the specific conditions in which electric motors are operated.

12.2. The local instructions must include those sections and paragraphs of this Standard Instruction that relate to all the main issues of operating electric motors installed at a given power plant in relation to local conditions.

12.3. The local operating instructions for electric motors should specify:

Permissible conditions and operating modes of electric motors;

Brief description of the main most powerful electric motors of different voltage classes, their supporting systems (cooling, excitation, lubrication, thermal and technological control and protection devices);

Distribution of responsibilities for servicing electric motors between power plant workshops;

The procedure for preparation for start-up, the procedure for start-up, shutdown and maintenance during normal operation and in emergency modes;

Procedure for admission to inspection, repair and testing of electric motors;

Safety and fire safety requirements specific to a specific group of electric motors,

12.4. The job description of each person charged with fulfilling the requirements of the local instructions for the operation of electric motors must include the relevant sections and points to be performed by these persons (duty electrician, duty driver, duty lineman, foremen).

12.5. In the relevant paragraphs of the local instructions, all instructions on modes, frequency of inspections and monitoring of the operation of electric motors must be given specifically for each type of electric motor in use. In addition, the frequency of measuring vibration of bearings of critical mechanisms must be established.

12.6. In the event of a change in the condition or operating conditions of electric motors, appropriate additions must be made to the local instructions and brought to the attention of employees for whom knowledge of these instructions is required, with an entry in the order log.

12.7. The instructions must be revised at least once every 3 years.

12.8. The local operating instructions for electric motors must be signed by the head of the electrical department and approved by the technical manager of the power plant.

12.9. The local operating instructions for electric motors should specify the list of emergency situations in accordance with local conditions.

12.10. The local instructions must contain a list of critical mechanisms, approved by the technical manager of the power plant, the re-enablement of which, after being switched off by their protections, is permitted after an external inspection.

12.11. The local operating instructions for electric motors should contain a list of protections, interlocks and alarms.

Application

Typical malfunctions of electric motors and their elimination

p.p.	Signs abnormal phenomenon	Probable Causes
	When starting electric motorbuzzes and doesn't turn around	Break of one phase in the stator circuit (fuse blown, poor contact in the switch, etc.). Break or poor contact in the rotor circuit (broken or burnt out rods in the area of the short-circuit rings).	Using a megohmmeter, identify the circuit break and eliminate it.
			Identify cracks or breaks in the rods by measuring the magnetic leakage flux around the rotor circumference using VAF-85 (for the method, see EC No. E-11/61 or § 6.60 SDME-81) or in another way.
		The stator winding circuit is assembled incorrectly (“star” instead of “triangle”, one phase is turned out, etc.). Mechanical binding in the drive mechanism or motor	Check the polarity of the terminals (determine the beginnings and ends of each phase) and assemble the stator winding circuit according to the manufacturer’s instructions. Bring the unit out for repairs and remove the jamming
	Sparks and smoke appeared from the engine when starting or during operation.	The rotor touching the stator due to a foreign object getting into the air gap, excessive wear of the bearings..	Bring the unit out for repairs to eliminate the defect.
		The rod of the short-circuited rotor winding has broken.	Take the engine out for repairs.
		Interturn short circuit in the stator winding	Repair winding fault
	At start-up, overcurrent protection operates	Short circuit in the stator circuit (in the cable, in the stator winding, terminal box).	Inspect the entire circuit up to the switching device, measure the insulation resistance of the circuit elements. If a short circuit is detected, remove the connection for repair. Change the protection settings in accordance with the conditions of detuning from the starting mode of the electric motor. Repair the drive mechanism



		The protection tripping current is low or the overload time delay is short. Drive mechanism faulty






4	Increased vibration of bearings	The alignment of the engine with the drive mechanism is incorrect.	Align the motor with the drive mechanism.


		The rotor is out of balance and the coupling is unbalanced.	Balance the rotor. Remove the coupling and balance it separately from the rotor. Construct the foundation in accordance with factory installation requirements.


		Insufficient foundation rigidity.
		There are gaps between the engine feet and the foundation	Eliminate gaps with gaskets.
		The motor feet on the Drive side are not pinned and the disc springs are not installed on the foundation bolts on the side opposite to the drive.	Install the pins and disc springs.
		The coupling is faulty, there are defects in the gear coupling due to improper engagement and improper tooth processing. There is a misalignment between the coupling halves mounted on the shafts, one or both coupling halves are beating, the pins of the elastic-finger coupling are installed incorrectly or are worn out.	Repair or replace the gear coupling. Check the correct fit and runout of both coupling halves, check the installation of pins in the coupling halves. If necessary, eliminate increased runout of the coupling halves, correct the installation of the pins or replace them with new ones.
		The temperature of the oil entering the bearings with forced lubrication is too low	During engine operation, the incoming oil should have a temperature of 25-45°C
	When the engine is running, rhythmic oscillations of the stator are observed.	Loss of contact or turn short circuit in the rotor winding	Carry out inspection and necessary repairs to the rotor.
	Water leak from the air cooler, the sensor for monitoring the presence of water in the engine is triggered	Possible cracks in the cooling tube at the flaring site or weakening of the flaring	Remove water from the engine. Conduct hydraulic tests of the air cooler to determine the location of the leak. It is allowed to plug one defective tube on both sides with plugs. If there are more damaged tubes, replace the air cooler
	Water leak in the electric motor AB(2AV)-8000/6000 in the weld or in the “fitting rod” connection of the rotor	Formation of a fistula or fissure	Cut out the leak to a depth of 4 mm. Solder with PSr45 solder and PV209X flux. After filling the hole with solder, maintain it for 1 minute. heating the rod neck to reduce stress in the “nozzle-rod” connection.
	in the “rod-short-circuit ring” connection of the rotor	Same	Cut and remove the technological steel bushing, cut out a groove 5 mm deep around the rod. Solder with PSr45 solder and PV209X flux, maintaining the heating of the rod neck as it cools.
	through tubes inside the stator core segment	Cracks, fistulas	Exclude a segment from the diagram using a jumper. It is allowed to exclude up to two parallel branches, the distance between which must be at least three packets. In the two extreme branches from each end of the core, segments are not allowed to be excluded.
	V collector stator	Loose fittings.	Tighten the nuts and lock.
		Loosening of the rubber seals in the end caps.	Tighten flanges or replace rubber seals
		Damage to the welds on the manifold.	Weld the welds
		Contamination of mating sealing surfaces	Clean sealing surfaces thoroughly
	Increased leakage of cooling water through the rotor AB (2АВ)-8000/6000	Wear of the fluoroplastic seal	Replace bushing
	Overheating of the entire stator winding and active steel. Increased temperature of cooling air at the outlet of the cooler	Increasing the load more than permissible.	Reduce the load to rated and below.
		Increase in cooling water temperature above normal	Increase water flow above normal, but not more than twice (in this case, the pressure in the cooler should not exceed the maximum permissible).
		Reducing water consumption	Clean the cooler by removing both covers. Rinse the tubes with a 5% solution of hydrochloric acid and clean them with special brushes (“brush”).
		Clogging of the inter-tube space of the cooler	Inspect the filters, thoroughly blow out the interpipe space with compressed air
	Increasing the water temperature at the outlet of the rotor, stator AB (2АВ) -8000/6000	Clogged rotor or stator cooling path	Backwash with water at a temperature of 80-90°C. If the effect of this method is insignificant, use chemical reagents (5% hydrochloric acid solution and 5% chromic anhydride solution)
	There are no readings from one of the resistance thermal converters	Broken sensor or test wiring	Replace the defective converter, eliminate the break or put the reserve cable core into operation
	Excessive bearing heating	Insufficient oil supply to the bearings (lubrication ring seizes). Excess or lack of lubrication in rolling bearings.	Increase the oil supply to the bearings and eliminate the ring malfunction. Check the quantity and quality of lubricant. If necessary, wash and fill the bearing with the required amount of lubricant.
		Grease or oil is contaminated	Clean the oil chambers of the bearings and change the oil.
		The wrong brand of oil was used.
		Axial impact on the motor rotor from the driven mechanism.	Check the alignment and connection of the motor to the driven mechanism
		No rotor run-up	Check the presence of adjusting shims between the bearing housing and the shield on the side of the working end of the shaft.
		Increased rotor vibration	See paragraph of this table
		Increased rotor vibration	See paragraph of this table
	Oil leakage from bearings	Increased oil consumption through bearings.	Adjust oil consumption.
	Oil leakage from bearings	The drain is clogged oil line Insufficient sealing of the joints between the labyrinth seals and the bearing housing	Clean the oil drain line. Replace gaskets between labyrinth seals and bearing housing
	Reduced insulation resistance of the stator winding	The winding is dirty or damp	Disassemble the electric motor, blow with dry compressed air, wipe the winding with a cloth moistened with detergent, and dry the insulation
	Increased brush sparking	Insufficient force to press the brushes against the slip rings.	Adjust the pressing force of the brushes.
		Interindustry rules for labor protection (safety rules) during the operation of electrical installations M.: Publishing House NC ENAS, 2003. . Rectangular plates for machines and devices. Dimensions.

INSTRUCTIONS

ON INSTALLATION AND OPERATION OF THREE-PHASE INDUCTION ELECTRIC MOTORS

1. SAFETY REQUIREMENTS.

Persons who have undergone technical instruction are allowed to install and maintain engines.

It is prohibited to operate motors without reliable grounding and mounting. For grounding, use only the special grounding clamps provided on the motors.

Installation, maintenance and dismantling of live motors is prohibited. It is prohibited to operate motors with the fan casing and terminal box cover removed.

2. PREPARATION FOR INSTALLATION.

Check that the supply voltage and frequency correspond to the data indicated on the motor nameplate.

Remove grease from preserved engine parts. Make sure the rotor rotates freely by hand. Measure the insulation resistance of the stator and rotor windings (only for wound-rotor motors) relative to the housing. If the resistance is below 0.5 MOhm, dry the engine. Dynamically balance the drive parts installed at the end of the shaft with a half key.

3. INSTALLATION.

When installing the engine, ensure free flow and exhaust of cooling air.

To avoid damage to the bearings when fitting the drive parts onto the shaft, it is necessary to provide a stop for the shaft on the opposite side. Secure the engine to a solid foundation or suitable foundation.

When connecting the motor to the drive mechanism, it is necessary to ensure the alignment and parallelism of the shaft connection. Permissible shaft misalignment is no more than 0.2 mm.

For a drive with a belt drive, it is necessary to ensure the correct relative position of the motor shafts and the drive mechanism. The minimum diameter of the pulley on the shaft and the maximum permissible belt tension are determined according to current standards. Load the second end of the shaft only using an elastic coupling.

4. PREPARATION FOR WORK.

Upon completion of installation, it is necessary to check the correct connection of the motor to the network according to the diagram on the cover of the terminal box and the passport (nameplate).

Check the tightness of the contact connections in the terminal box, fastening connections and seals in the fittings, and the serviceability of the grounding.

To check the correct installation, operation and direction of rotation of the drive, test run the engine at idle speed. To change the direction of rotation of the motor, you need to swap any two wires of the power cable.

After starting at idle speed and eliminating any observed deficiencies, start the engine under load.

5. DURING OPERATION IT IS NECESSARY:

Conduct general monitoring of engine operation in order to monitor normal technical condition,

Carry out maintenance systematically (frequency - at least once every two months),

Carry out routine repairs if deviations in the bed heating level, noise and vibration levels and other deviations in engine operation are noticed, but at least once a year.

6. MAINTENANCE.

When servicing the engine, it is necessary to carry out an external inspection, clean the engine of dirt, check the reliability of grounding and the condition of the contacts in the terminal box, and measure the insulation resistance.

Check the mechanical fastening of the motor to the installation site and the connection to the drive mechanism.

7. DURING CURRENT REPAIRS IT IS NECESSARY:

Dismantle and disassemble the engine, wash, clean and dry parts. Inspect bearings, stator and rotor to detect mechanical damage, identify parts that need to be replaced, restored and adjusted.

Replenish the felt seals along the shaft line with transformer oil after 3000 hours of operation, but at least once a year.

For engines with open bearings, replenish or completely replace the lubricant after 6,000 - 10,000 operating hours, but at least once every two years. For replenishment, use only mineral oil-based lubricants with a lithium thickener.

Bearings should be replaced when the operating time exceeds 20,000 hours and when there is increased bearing knock, noise during engine operation, the rotor touching the stator, or the presence of mechanical damage. Remove bearings from the shaft only using a puller.

8. STORAGE.

Engines can be stored in containers or without them in closed, ventilated rooms, the atmosphere of which does not contain acidic, alkaline and other vapors that have a harmful effect on insulation and coatings.

Sharp fluctuations in temperature and air humidity that cause the formation of condensation (dew) are unacceptable.

This Standard Instruction is intended to provide guidance for the operation of electric motors in auxiliary installations of power plants and contains the basic requirements to ensure reliable and safe operation of electric motors.
The standard instructions apply to asynchronous and synchronous electric motors with a power of over 1 kW, used to drive auxiliary mechanisms of power plants with a voltage of 0.4 kV; 3.15kV; 6.0 kV and 10 kV, as well as DC electric motors used to drive fuel feeders, emergency turbine oil pumps and shaft seals of hydrogen-cooled turbogenerators.
This Standard Instruction is the basis for drawing up local instructions at each power plant, which must take into account the specific conditions of the electric motors being operated, the requirements and recommendations of the manufacturers.

Designation:	SO 34.45.509-2005
Russian name:	Standard instructions for the operation of electric motors in auxiliary installations of power plants
Status:	valid (Date of the first inspection of this RS - 2010, inspection frequency - once every 5 years)
Replaces:	TI 34-70-023-86 “Standard operating instructions for synchronous electric motors of ball mills Ш-50” (SPO Soyuztekhenergo, 1986) RD 34.45.507 “Standard operating instructions for large electric motors with water-cooled rotors for driving feed pumps” ( SPO Soyuztekhenergo, 1989) RD 34.45.509-91 “Standard instructions for the operation of electric motors in auxiliary installations of power plants” (SPO ORGRES, 1991)
Date of text update:	01.10.2008
Date added to the database:	01.02.2009
Effective date:	01.09.2005
Designed by:	Branch of OJSC "Engineering Center UES" - "Company ORGRES" 105023, Moscow, Semenovsky lane, 15
Approved:	Branch of OJSC "Engineering Center UES" - "Company ORGRES" (04.08.2005)
Published:	CPTIiTO ORGRES No. 2005

BRANCH OF JSC ENGINEERING CENTER UES - FIRMAORGRES

STANDARD INSTRUCTIONS
ON OPERATION OF ELECTRIC MOTORS IN INSTALLATIONS OF OWN NEEDS OF POWER PLANTS

SO 34.45.509-2005

Moscow 2005

Developed by:Branch of OJSC "Engineering Center UES" - "FirmaORGRES"

Executor: V.A. VALITOV

Approved:Chief Engineer of the Branch of OJSC "Engineering Center UES" - "Company ORGRES" V.A. KUPCHENKO08/04/2005

The period for the first inspection of this RS is 2010, inspection frequency is once every 5 years

Keywords: electric motor, mechanism, insulation, winding, bearing, personnel, maintenance, start-up, shutdown

STANDARD INSTRUCTIONS FOR THE OPERATION OF ELECTRIC MOTORS IN INSTALLATIONS OF OWN NEEDS OF POWER PLANTS

SO 34.45.509-2005

Put into effect
from 01.09.2005

This Standard Instruction is intended to provide guidance for the operation of electric motors in auxiliary installations of electric power plants and contains the basic requirements to ensure reliable and safe operation of electric motors.

The standard instructions apply to asynchronous and synchronous electric motors with a power of over 1 kW, used to drive mechanisms for the auxiliary needs of power plants with a voltage of 0.4 kV; 3.15kV; 6.0 kV and 10 kV, as well as DC electric motors used to drive fuel feeders, emergency turbine oil pumps and shaft seals of hydrogen-cooled turbogenerators.

With the publication of this Standard Instruction the following become invalid:

“Standard instructions for the operation of electric motors in auxiliary installations of power plants: RD34.45.509-91” (M.: SPO ORGRES, 1991);

“Standard operating instructions for large electric motors with water-cooled rotors for driving feed pumps: RD34.45.507” (M.: SPO Soyuztekhenergo, 1989);

“Standard operating instructions for synchronous electric motors of ball mills Ш-50: TI 34-70-023-86” (Moscow: SPO Soyuztekhenergo, 1986).

1 General requirements

1.1. All electric motors installed in the technological workshops of a power plant must have an abbreviated marking on the body, a general design and corresponding to the executive working technological diagram, and an indicator of the direction of rotation. Buttons or keys for controlling switches (circuit breakers or magnetic starters) of electric motors must have clear inscriptions indicating which electric motor they relate to, as well as which button or which direction of turning the key relates to starting and which to stopping the electric motor. Marking of switching devices, buttons and control keys must be carried out by electrical shop personnel.

1.2. An emergency shutdown button must be located near the installation site of electric motors with remote or automatic control. The emergency button may only be used for emergency stop of the electric motor. Emergency shutdown buttons must be protected from accidental or erroneous operation and sealed. Monitoring the safety of the seals should be carried out by the personnel on duty in the electrical workshop.

1.3. Electric motors with dual control (local and remote control by the operator station of the automated process control system) must be equipped with a switch for selecting the type of control, located at the local push-button control station, and an indication of the switch position.

The degree of protection of electric motors of a closed, ventilated design, intended for operation in the open air and in rooms with high humidity and dust in the ambient air of no more than 10 mU / m 3, must be not lower than I P44 according to GOST 17494.

The degree of protection of the output device for both versions of electric motors must be at least I P54.

Motors and their output devices intended for installation in rooms with high dust levels that require periodic water cleaning must have a degree of protection of at least IP 55.

1.5. Exposed rotating parts (couplings, pulleys, shaft ends, toothed belt drives) must be guarded.

1.7. For AC electric motors with a power over 100 kW, if it is necessary to control the technological process, as well as electric motors of mechanisms subject to technological overloads, currentator control must be provided. The instrument scale is graduated in amperes for individual control and in percentage for a selective control system. The ammeter scale must have a line corresponding to the rated stator current.

On DC electric motors for driving fuel feeders, emergency oil pumps of turbines and shaft seals of hydrogen-cooled turbogenerators, regardless of their power, the armatures must be controlled. In cases where information on the MV unit is displayed on the video monitor of the operator station of the automated process control system, the indication of the current values of currents that exceed the rated value must differ from the indication of currents in the normal mode of the electric motor.

1.8. Disconnected electric motors that are in reserve must be constantly ready for immediate start. After starting the backup electric motor, it is necessary to inspect the electric motor and ensure its normal operation.

1.9. Electric motors that are in reserve must be put into operation, those that are not working must be transferred to reserve at least once a month according to a schedule approved by the technical manager of the power plant. In this case, for outdoor electric motors that do not have heating, the insulation resistance of the stator winding and the absorption coefficient must be checked.

Automatic transfer switching devices (ATDs) must be checked at least once a quarter according to the program and schedule approved by the technical manager of the power plant.

1.10. Ventilated electric motors installed in dusty rooms with high humidity and air temperature, must be equipped with devices for supplying clean cooling air.

1.11. Air ducts for supplying and discharging cooling air must be made of non-combustible materials and have a mechanically strong and gas-tight design. Devices for regulating air flow and excess air pressure after final adjustment must be securely fastened and sealed. The tightness of the cooling path (air ducts, units connecting air duct casings to the electric motor housing, dampers) must be checked at least once a year.

1.12. Individual electric motors for external cooling fans should automatically turn on and off when the main electric motors are turned on and off.

1.13. The upper points of the water chambers of air coolers of electric motors must be equipped with taps to control the complete filling of the air coolers with water.

1.15. On electric motors that have forced ventilation with separately installed fans, protection must be installed that acts on a signal and shuts down the electric motor when the motor temperature rises above the permissible control level. at certain points or when ventilation stops.

1.16. Electric motors AB (2AV)-8000/6000, which were previously used to drive power supply pumps with water-cooling systems for the rotor winding and active stator steel, as well as electric motors with built-in water-air coolers, must be equipped with devices that signal the appearance of water in the housing. In addition, electric motors of the first group must be equipped with protection that acts on the signal when the flow of condensate through the active parts decreases and turns off with a time delay of no more than 3 minutes when the circulation of the cooling medium stops.

Operation of equipment and equipment of water cooling systems, the quality of condensate in these systems and cooling water of air coolers must comply with the instructions of the factory instructions.

1.17. To blow electric motors with compressed air during repairs, use air with a pressure of no more than 0.2 MPa (2 kgf/cm2). The air must be clean, free of moisture and oil. If possible, blowing should be done outdoors or in a special blowing chamber, or dust should be removed with a vacuum cleaner.

1.18. For installation, disassembly and assembly of electric motors, stationary, mobile or inventory lifting and transport devices must be provided.

1.19. Spare parts for electric motors should be stored at the power plant or repair facility and replenished as they are used.

1.20. For each electric motor with a power of 1 kW and above, regardless of operating voltage, there must be the following technical documentation:

Electric motor passport;

Acceptance test protocol;

Winding connection diagrams (if they are not standard);

Schematic and installation (executive) diagrams of control, alarm and relay protection. In the case of electric motors of the same type, it is allowed to have the indicated diagrams in the documentation of one of the electric motors;

Technical reports on damage to electric motors;

Operation log,

1.21. Operational information on the electric motor is entered into a journal (form) by a senior foreman or foreman.

2 Operating conditions and permissible operating modes of electric motors

2.1. To ensure normal operation of electric motors, the voltage on the auxiliary buses must be maintained at 100-105% of the nominal value. If necessary, it is allowed to operate electric motors while maintaining their rated power in case of voltage deviations in the network up to ±10% of the rated value. Monitoring of the voltage level on the buses of own needs should be carried out using measuring instruments (according to the indication on the monitors of automated process control systems) installed on control panels (control room, main control room), as well as devices connected to voltage transformers or directly to the buses of sections and power assemblies in the premises of switchgear switchgear, switchgear distribution systems and etc.

2.2. If the frequency of the supply network changes within ±2.5% (1.25 Hz) of the rated value, the electric motor can operate with the rated load.

2.3. The rated power of electric motors must be maintained with a simultaneous deviation of voltage up to ±10% and frequency up to ±2.5% (±1.25 Hz) of the nominal values, provided that when working with increased voltage and reduced frequency or with reduced voltage and increased frequency, the sum of the absolute values of the deviations voltage and frequency does not exceed 10%.

2.5. Electric motors must allow direct starting from full mains voltage and ensure the mechanism starts both at full mains voltage and at a voltage of at least 80% of the rated voltage during the starting process. The values of the moments of resistance on the motor shaft during starts, as well as the permissible moments of inertia of the driven mechanisms, must be established in the technical specifications for motors of specific types.

2.6. Two-speed electric motors, as a rule, allow direct starting only of a winding with a lower rotation speed, followed by switching (if necessary) to a winding of a higher rotation speed.

The admissibility of direct starting from a winding of higher rotation speed and the number of such starts are determined by the technical conditions for a specific type of electric motor.

Switching of such motors should be done with no more than two switches.

Simultaneous activation of both windings is not allowed.

The completion of installation and commissioning work must be recorded by the responsible persons of the installation and commissioning organizations in the “Equipment Input Log from Installation”, stored on the central control panel.

4.2. During installation and adjustment, as well as upon completion, the electrical part of the mounted electric motor must undergo unit testing and acceptance by the foreman of the corresponding repair department or ETL group. The completion of unit acceptance is recorded in the “Equipment Entry from Installation Log”, after which a test run is allowed.

4.3. Readiness for a test run is determined by the management of the electrical shop, based on the condition of the electric motor and the results of unit acceptance. At his request, the shift supervisor of the electrical shop instructs subordinate personnel to assemble the electrical circuit of the electric motor being tested. Before this, the duty personnel of the electrical and technological shops must inspect the electric motor to the extent specified in the paragraphs and these Instructions.

4.5. The conduct and results of the test launch must be noted by the launch manager in the “Equipment Entry from Installation Log” and by the duty personnel in the operational logs. Subsequent startups and assemblies of the electrical circuit can be carried out at the request of installation, commissioning and operating personnel through the shift supervisor of the technological workshop.

4.6. The electric motor is accepted into operation upon satisfactory results of comprehensive testing, after which the electric motor is transferred for service to the operating personnel with an entry in the “Equipment Commissioning Log from Installation”.

4.7. Testing and running-in of electric motors after major and ongoing repairs is carried out installation personnel after making entries about the completion of repair work in the “Logbook for input and output of equipment for repair.”

4.8. When preparing the electric motor for start-up (for the first time or after repair), the duty personnel of the technological workshop must check the following:

4.8.1. Completion of all work on the mechanism, closing of orders, absence of people and foreign objects on the unit and inside the fences.

4.8.2. Availability oil in oil pans and its level oil indicator in electric motors with plain bearings and annular lubricant. In electric motors with forced lubrication, readiness for operation oil systems.

4.8.3.Presence of pressure And flow of water through air coolers (and oil coolers when their availability).

4.8.4. Shut-off position and control valves mechanisms taking into account the instructions point .

4.8.5.Sensor serviceability alarm devices and technological protections, thermal control devices and technological control(if available).

4.8.7. On electric motors AB (2AV)-8000/6000, equipped with direct water cooling systems for the stator core and rotor winding, as well as units with a forced lubrication system for the motor and mechanism bearings, prepare for start-up and put these systems into operation, ensuring upon completion of the repair (installation):

Flushing of pipelines and circuit elements with condensate (oil) in addition to the active parts of the electric motor (bearings);

Filling the systems with clean condensate (oil) and checking that there is no airing of the elements of the hydraulic circuits;

Alternate short-term testing of pumps while idling and checking their performance;

Turning on the circulation of condensate (oil) through the active parts of the electric motor (unit bearings) with checking the tightness of the check valves of the pumps and adjusting the flow rate, pressure and temperature of the working medium within the required limits;

Testing (with the involvement of the on-duty personnel of the electrical shop and CTAI) of ATS pumps, process alarm devices, interlocks and protections, putting them into operation;

Inspection of systems included in operation for the absence of leaks.

4.8.8. The mechanism is ready to start.

4.9. If there are no comments on the condition of the unit, the power plant shift supervisor must give the command to the electrical department shift supervisor to assemble the electrical circuit of the electric motor. Upon receipt of such an order, the electrical shop personnel on duty must:

4.9.1. Check the completion of work and closure of all issued work orders on the electric motor and its electrical equipment. Make sure there is an extract in the “Equipment Input/Output Log for Repair”.

4.9.2. Inspect the electric motor and its electrical equipment; check the connection of the power cables to the motor terminals, the absence of bare current-carrying parts, the density of the output device or the closure of the terminal chamber, the serviceability of the starting and switching equipment, the condition of the brush device, the presence and serviceability of the protective grounding of the electric motor.

4.9.3. Make sure that the area around the electric motor and the electric motor itself are clear of dirt and foreign objects.

4.9.4. Remove portable grounding connections or disconnect the grounding blades.

4.9.5. Using a megohmmeter, check the integrity of the phases of the stator winding and the supply cable and the condition of the insulation of the windings, which must correspond to the following.

For new electric power units put into operation for the first time motors and electric motors, who have undergone rehabilitation or major repairs and reconstruction in a specialized repair shop enterprise, acceptable values insulation resistance winding st ator, absorption coefficient and nonlinearity coefficient, being the conditions of their inclusions in work without drying are given in tables 5 and 6.

Rotor winding insulation resistancesynchronous electric motors and asynchronous electric motors with a phase rotor for a voltage of 3 kV higher or power more than 1 MW, switched on for the first time during operation, it must be at least 0.2 MOhm, and after completion of scheduled repairs it is not standardized.

For electric motorsvoltage above 1 kV in operation, the permissible value of the insulation resistance of the stator winding R 60 and absorption coefficient at the end of capital or no current repairs are standardized, but must be taken into account when deciding on the need for their drying. In operation, determination of the absorption coefficient is mandatory for electric motors with voltages above 3 kV or power greater than 1 MW. It should be taken into account that if the engine is under repair for a long time, its stator winding may become moist, which may require drying and, for this reason, delay its commissioning. Therefore, when starting a scheduled repair unit, measurement Insulation of the stator winding of electric motors of critical auxiliary mechanisms should be carried out no later than 2 days. before the scheduled completion date of the repair. The insulation resistance of the stator windings of electric motors with voltages higher than 1 kV, together with the supply cable, which are started up after a long period of inactivity or being in reserve, is also not standardized. It is considered sufficient if the specified resistance is at least 1 MΩ per 1 kV of the rated line voltage. Insulation resistance is measured at a nominal winding voltage of up to 0.5 kV inclusive with a mega-ohmmeter for a voltage of 500 V, at a rated winding voltage of over 0.5 kV to 1 kV - with a mega-ohmmeter for a voltage of 1000 V, and for a winding voltage above 1 kV - with a mega-ohmmeter for a voltage of 2500 V.

Table5

Acceptable values of insulation resistance, absorption coefficient and nonlinearity for stator windings, new electric motors put into operation for the first time and electric motors that have undergone restoration or major repairs and reconstruction at a specialized repair enterprise

Power, rated voltage of the electric motor, type of winding insulation

Criteria for assessing the state of stator winding insulation

Insulation resistance value, MOhm

Absorption coefficient value R 60 ² / R 15 ²

Coefficient value nonlinearity ** K u = I nb × U nm / I nm × U nb

1. Power over 5MW, thermoset and mica compound insulation

No more than 3

2. Power 5 MW and below, voltage above 1kb, thermosetting insulation

Not lower than 10MΩ per 1kV rated line voltage at temperature* 10-30°C

Not less than 1.3 at temperature* 10-30°C

Not lower than 1.2

4 . Electric motors with mycalentcompounded insulation, voltage over 1 kV. power less than 1 MW, except as specified in paragraph 3

Not lower than the values indicated in table 6

Not lower than 1Mohm at a temperature* 10-30°C

* At temperatures above 30°C the permissible insulation resistance value is reduced

2 times for every 20°C difference between the temperature at which the measurement is performed and 30°C,

To avoid local overheating of the insulation by leakage currents, voltage withholding at the next stage is allowed only if the leakage currents do not exceed the values indicated below:

Multiplicity of test voltage in relation to U nom			1.5 and above
Leakage current, µA			1000

Table 6

The lowest permissible insulation resistance values for electric motors (see Table 5, paragraphs 3 and 4)

Winding temperature,°C	Insulation resistance R 60 ² , MOhm at rated winding voltage, kV
Winding temperature,°C	3-3,15	6-6,3	10-10,5

In case of an unacceptable decrease in insulation resistance and unsatisfactory values of the absorption coefficient and nonlinearity, the electric motor must be dried.

4.9.6. Remove safety signs and prohibition warning posters from the electric motor and switching equipment, which was used to disassemble the electrical circuit of the electric motor.

4.9.7. Assemble the electrical circuit of the electric motor and lubrication oil pump (if any), supply operational current to the control, protection, alarm circuits, and to the automatic and interlock circuits. In preparation for operation of electric motors of ball mills, in addition to assembly electrical diagram synchronous motors and their oil stations, it is necessary to assemble electrical circuits of their exciters (excitation systems) and fans of the forced cooling system (if the latter are present).

4.9.9. Report to the person who gave the order to prepare the electric motor for start-up about assembling the electrical circuit And motor readiness inclusionto the network. Make an entry in the operational journal.

5.1. The electric motor is switched on by the duty personnel of the technological workshop servicing this mechanism. About the upcoming launch of a powerful or the responsible electric motor located long-term reserve(more than 1 month) or after repair, the workshop personnel servicing the starting mechanism must notify the electrical workshop personnel, who are obliged to carry out pre-start operations in accordance with paragraph 4.9. The exceptions are launches related to the liquidation of an emergency situation, and launches electric motors, switched on by AVR.

5.2. When turning on the electric motor locally, its control key (button) should be kept in the “On” position until the electric motor turns.

5.3. At the location where the electric motor is installed, it is necessary to monitor the starting mode. The supervisor of the technological workshop must check the correct rotation, ease of movement, and the absence of extraneous noise. In the event of sparks, smoke from the windings or bearings, extraneous sound, knocking and rubbing, you should immediately turn off the electric motor with the emergency button.

If the start-up proceeds normally, the supervisor must inspect the electric motor, make sure that the bearings are operating normally and that there is no unacceptable heating or vibration.

5.4. The person performing the start must monitor the start using an ammeter or stator current indication on the screen of the operator station of the automated process control system (if available).

When starting an asynchronous electric motor with a squirrel-cage rotor, the toxtator exceeds the rated value by 5-7 times and remains practically unchanged throughout the entire start-up. As soon as the rotor speed reaches 90% of the rated value, the stator current sharply decreases to a value close to the rated value or lower. The start-up time, depending on the flywheel of the mass unit, ranges from several seconds (circulation, feed pumps) to tens of seconds (blower fans, smoke exhausters).

When starting a synchronous motor of a ball mill, it is initially started asynchronously due to the starting short-circuited winding located in the pole pieces. Upon reaching the subsynchronous rotation speed, the motor is automatically excited by supplying direct current to the circuit of the working rotor winding, and the electric motor is drawn into synchronism. Signs of involvement engine deceleration synchronism is determined by the presence of excitation current and the steady position of the ammeter needle in the stator winding circuit.

5.5. If, at the moment of turning on the electric motor with a voltage above 1000 V, the signal “Ground on the section...” appears, the electric motor should be turned off and the duty personnel of the electrical workshop should be informed about this.

5.6. If the engine turns off during start-up, then it is necessary to acknowledge the control key, inspect the electric motor and inform the duty personnel of the electrical department to take measures to determine the reason for the shutdown and activation of the protection.

5.7. Two-speed motors, as a rule, should be connected to the network on a winding of lower rotation speed with subsequent switching (if necessary) to a winding of higher rotation speed.

Simultaneous activation of both windings is not allowed.

5.8. Starting of electric motors driving fans (smoke exhausters, blower fans, hot blast fans, etc.) must be done with the dampers closed.

5.9. Electric motors with squirrel-cage rotors are allowed, subject to the conditions of their heating, to be started from a cold state 2 times in a row, from a hot state - 1 time, if the factory instructions do not allow more starts. Subsequent starts are allowed after the electric motor has cooled for a period of time determined by the factory instructions.

Subsequent starts of electric motors with voltages over 1000 V are allowed after 3 hours.

6 Supervision of electric motor operation

6.1. Constant supervision of the operation of electric motors must be carried out by the duty personnel of the technological workshop servicing the mechanisms. In addition, the condition and operating mode of electric motors must be monitored by the personnel on duty in the electrical workshop through periodic scheduled walk-throughs and inspections of all electric motors, both working and in reserve. Regardless of this, all electric motors with voltages above 1000V at least 2 times a month, and the rest must be inspected by a repairman once a month.

Extraordinary inspections of electric motors must be carried out when their protection is switched off and there is a sudden change in climatic conditions (for outdoor units) and operating mode.

6.2. Electric motors that are in reserve for a long time and automatic reserve switching devices must be inspected and tested together with mechanics according to a schedule approved by the technical manager of the power plant, but at least once a month.

6.3. During operation of the electric motor, the personnel on duty in technological workshops are obliged to:

6.3.2. Control heating and vibration of bearings. If an increase in temperature or vibration of the bearing is detected by touch, it is necessary carry out a control measurement through a portable device (with lack of stationary devices).

Extremely valid values temperature vibration electric motor bearings are given in paragraphs and.

6.3.3. Check the oil level in electric motors with ring-lubricated bearings. Sleeve bearing chambers must be filled out oil up to the mark on the oil level gauge or, if there is no mark, to the middle of the oil indicator glass on bearing. If necessary, add oil. recommended by the manufacturer brand (T22, T30, Tp30 or other). Frequent topping up (more than once a month) with indicates its leak. Especially oil leakage inside the housing is dangerous electric motor, because the it may cause corrosion cover, varnish and reduction of insulation resistance of the stator winding.

IN electric motors with With a forced lubrication system, control the oil pressure in the oil pressure line and the amount of oil at the bearing drain, which should fill approximately 1/2 to 1/3 of the cross-section of the oil drain line.

6.3.5. Pay attention to the appearance of abnormal noise in the rolling bearings, indicating an insufficient amount of lubrication or the appearance of defects on the surfaces of the races and rolling elements, and report this to the shift supervisor of the electrical department.

If it is impossible to reduce temperatures to acceptable values, the engine must be stopped in agreement with the shift supervisor of the electrical department.

6.3.7. Observe the brush apparatus of synchronous electric motors. If unacceptable sparking, increased vibration and other defects are detected, report this to the shift supervisor of the electrical shop so that measures can be taken to normalize the operation of the current collection unit.

6.3.8. Monitor the operating mode of air coolers, as well as direct water cooling systems for AB (2AV)-8000/6000 electric motors, ensuring that the pressures, flow rates and temperatures of cooling water and condensate are maintained within acceptable limits.

6.3.9. Make sure that all rotating parts of the electric motor (end ends, coupling halves, pulleys, etc.) are securely covered with guards.

6.3.10. Do not allow steam, water or oil to enter the motor output device or inside its housing.

6.3.12. Keep records of electric motor starts and stops.

6.3.13. Notify the shift supervisor of the electrical department about any abnormalities in the operation of the electric motor.

6.4. When walking around and inspecting the electric motor, the personnel on duty in the electrical shop must monitor:

Load, housing heating, temperature of the cooling medium, rolling bearings, copper and stator core (without the right to regulate them);

Vibration of bearings and housing (to the touch);

No leaks from air coolers built into the stator and water supply units to the active parts of the electric motor inside their housings;

Condition of lighting of the service area;

Condition of grounding of the electric motor housing;

Terminal box condition;

No heating of contact connections and no smell of burnt insulation;

The condition of the brush-contact devices of alternating current electric motors (the degree of sparking, heating and vibration of the electric brushes, the force of pressing the brushes against the slip rings, contamination of the device with brush dust, the presence of stuck, extremely worn brushes, as well as brushes with mechanical damage to their fittings, etc.) are monitored.

6.5. If during inspections emergency situations and malfunctions in the operation of electric motors are identified, it is necessary to eliminate them, provided that the operations carried out in this case can be carried out by the production instructions and safety rules alone by the person on duty. Otherwise, it is necessary to immediately inform a higher operational person about the emergency condition and the need to take urgent measures.

A list of the most typical malfunctions of electric motors and methods for eliminating them are given in the appendix to this Instruction.

6.6. The electrical shop staff on duty switches off the electric motor or changes its operating mode only with the permission of the shift supervisor of the workshop where the electric motor is installed, with the exception of emergency cases (see section 7).

6.7. All work related to the repair of electric motors is carried out by repair personnel of the electrical shop or a specialized repair organization.

Urgent work to eliminate electric motor malfunctions that threaten to disrupt the normal operation of the unit (station) is allowed to be carried out by duty personnel. In this case, before work, all organizational and technical measures must be taken to prepare the workplace.

7 Emergency shutdown of the electric motor

7.1 The electric motor must be immediately (emergency) disconnected from the network under the following circumstances:

Accidents with people;

The appearance of smoke or fire from the housing (output device), bearings, oil pipes of the electric motor, its starting and exciting devices;

Fire in oil pipelines and the impossibility of extinguishing it;

Breakage of the driven mechanism;

7.2 The electric motor must be stopped after starting the electric motor of the standby unit (if available) or after warning the technological shift supervisor in the following cases:

The appearance of abnormal noise in the electric motor;

The smell of burnt insulation appears;

A sharp increase in vibration of the electric motor or the mechanism driven by it;

Unacceptable increase in bearing temperature;

Electric motor overload above permissible limits;

Electric motor operation in two phases;

There is a threat of damage to the electric motor (flooding with water, steaming, etc.).

8 Action of personnel in case of automatic shutdown of the electric motor by protections

8.1. During operation of the electric motor, it may be automatically disconnected from the network by technological or electrical protection.

When a running electric motor is automatically switched off, the on-duty personnel of the process shop must immediately check the successful activation of the backup unit from the ATS. If the ATS fails or is absent, it is necessary to turn on the electric motor of the backup unit by hand, notifying the shift supervisor of the workshop in which the electric motor is installed and the shift supervisor of the electrical workshop.

After turning on the electric motor of the standby unit, the personnel on duty in the electrical shop must, on the switched-off electric motor:

Check for the absence of signs leading to an emergency shutdown and indicated in;

Find out the reason for the shutdown using the indicator relays and the corresponding alarm;

Carry out an external inspection of the switched-off electric motor in order to look for obvious signs of a short circuit;

Using a megohmmeter, check the insulation condition of the stator winding and power cable.

The duty personnel of the technological workshop must:

Check the operation of the switched-on electric motor;

Observe the switched-on electric motor for 1 hour;

Record the observation results in the operational journal.

8.4. If the electric motor of the critical protection mechanism is turned off and there is no backup electric motor, it is allowed to restart the electric motor after an external inspection and obtaining permission from the shift supervisor of the electrical department and the station shift supervisor with registration of all instructions and operations in the operational log.

8.5. Restarting electric motors in cases of backup protection until the cause of the shutdown is determined is not allowed.

8.6. In the event of an emergency shutdown of the electric motor as a result of a short circuit in the winding or at its terminals, it may catch fire. Extinguishing an electric motor fire should be carried out after disassembling the electrical circuit using a carbon dioxide fire extinguisher or water. It is prohibited to extinguish a burning electric motor with a foam fire extinguisher and sand.

9 Taking the electric motor out for repair

9.1. No repair work is allowed on a rotating electric motor, except for those that do not involve approaching live and rotating parts (cleaning, marking, painting, repairing bases and foundations).

During a planned shutdown of the electric motor, the load is reduced taking into account the instructions in paragraph , the motor switch is turned off, the excitation is turned off (for synchronous electric motors), the oil pumps of the forced lubrication system are turned off (after the rotor has stopped rotating), the water cooling pumps of the active parts of the engines are turned off, water is removed and the cooling system is dried with compressed air (for electric motors type AB (2AV)-8000/6000), stopping the supply of cooling water to the air cooler and disassembling the electrical circuits of the electric motor itself and the electric motors of its supporting systems.

During long shutdowns or breaks in operation, if the ambient temperature is below 5ºC, electric heaters on outdoor electric motors must be turned on, if they are provided by the manufacturer.

9.3. An entry must be made in the operational log of the duty personnel about for what work, in what workshop and at whose request the electric motor was stopped.

9.4. After the electric motor is switched off by the duty personnel of the technological workshop, a prohibiting poster “Do not turn on!” must be hung on the key or control button of the stopped electric motor. People are working." In addition, measures must be taken to prevent the rotation of the electric motor from the mechanism side. Such measures are closing the pressure valve, guide vanes, gate valves, and tying the steering wheels with a chain and locking them, hanging a prohibitory sign “Do not open! People are working."

9.5. Until the complete completion of the repair work and until the closure of the work order, the duty personnel of the technological workshop do not have the right to remove these prohibitory posters. Their removal must be done before assembling the electric motor circuit as directed by the workshop shift supervisor.

9.6. To carry out repair work on the rotating parts of a mechanism or electric motor or on its live parts, the duty personnel of the electrical workshop, at the direction of the shift supervisor of the electrical workshop or at the request of the station shift supervisor, must take the following measures to prepare the workplace.

9.6.1. The electrical circuit of an electric motor with a voltage above 1 kV must be disassembled, creating a visible gap by rolling out the switchgear trolley into a repair position. The protective curtains must be locked and a prohibitory sign “Do not turn on!” must be posted on them. People are working." A grounding knife must be included in the switchgear cell.

For a two-speed electric motor, the power supply circuits of the stator windings must be disconnected and disassembled.

9.6.2. The electrical circuit of electric motors with a voltage of 380 V connected to the RUSN-0.4 kV section must be disassembled by turning off the circuit breaker and installing its trolley in the repair position. A prohibitory poster “Do not turn on!” must be posted. People are working,” the power cable was disconnected from the motor terminals and a portable grounding was installed.

9.6.3. The electrical circuit of 380V electric motors connected to power assemblies must be disassembled by turning off the circuit breaker; a poster “Do not turn on!” must be hung on its handle. People are working." On live parts after the circuit breaker, the absence of voltage must be checked and the grounding knife must be turned on, and if it is absent, the power cable must be disconnected from the motor terminals and a portable grounding must be installed.

9.7. Upon completion of the preparation of workplaces, the operational log of the shift manager of the electrical workshop should record at whose direction, the application of which workshop and for what work the electric motor was taken out for repair.

9.8. If the power cable of the electric motor of the mechanism being repaired is grounded on the side of the cell or assembly, then disconnecting the cable from the motor terminals (at the request of the technological workshop) should be carried out only in cases where, during the repair, movement, rotation or removal of the electric motor from the foundation is required.

As a rule, disconnecting cables from the terminals of electric motors should be done when a unit or other technological equipment is removed for major repairs.

9.9. When stopping the mechanism only to repair the electric motor, disconnecting the cable from the motor terminals, if grounding is installed on the RUSN side, must be carried out by personnel repairing the electric motor.

9.10. In all cases, portable grounding must be installed at the disconnected ends of the cable by the electrical shop personnel on duty.

9.11. Upon completion of the repair, the connection of the power cable to the motor terminals, as a rule, should be carried out by the personnel repairing the motor. As an exception, in emergency cases, the cable connection is allowed to be made by the personnel on duty.

9.12. Repair work on electric motors located on the territory of the technological workshop is carried out according to orders and orders issued by the electrical workshop on a daily basis. the decision of the shift manager of the technological workshop, who must record this in his operational log. The permission must be transferred by telephone to the personnel on duty in the electrical workshop (permitting) and recorded in its operational log.

9.13. During major and current repairs of the unit, permission to work on electric motors located in the premises of the technological workshop and located within the coverage area of the general order must be carried out according to the orders and orders endorsed by the responsible manager for the general order.

Permission for daily access from the shift supervisor of the technological workshop is not required in this case. Permission to work is carried out by the staff on duty in the electrical workshop. The provision of work orders and orders for approval to the responsible manager for general work must be done by the work manager for the order for repair of the electric motor.

9.14. Testing of control circuits, protection devices and technological interlocks operating on the electric motor switch is allowed to be carried out on the unit being repaired (with a valid general order) provided that the switchgear trolley is installed in the test position and there is grounding in the switchgear cell.

9.15. The testing must be carried out at the request of the ETL personnel or the thermal automation shop with the permission of the shift supervisor of the technological workshop after confirmation by the shift supervisor of the electrical workshop that the above test conditions have been met.

9.16. Testing of technological protections and interlocks should be carried out with a minimum number of operations with switching equipment (to reduce wear and maintain the settings of the switch and contact block).

9.18. The electric motor being tested is switched on by the personnel on duty of the technological workshop at the direction of the shift supervisor of the technological workshop and at the command of the work manager conducting the testing.

During testing, a prohibiting poster “Do not turn on! People are working” is removed from the switch control key and installed again after testing.

10 Maintenance, scope of repairs and testing of electric motors.

10.1. Maintenance and repair involve the implementation of a set of works aimed at ensuring the good condition of electric motors, reliable, safe and economical operation, carried out with a certain frequency and sequence at optimal labor and material costs.

10.2. Maintenance that does not require taking electric motors out for routine repairs includes:

Scheduled walk-throughs and technical inspection of operating electric motors;

Monitoring the technical condition of electric motors using external monitoring or diagnostic tools, including monitoring with portable equipment;

Replenishing and replacing lubricated parts, cleaning oil and water filters, tightening oil seals, checking control mechanisms, etc.;

Elimination of water, oil leaks and other individual defects identified during condition monitoring and performance testing;

Adjustment and purging of the brush apparatus of synchronous electric motors;

Inspection and testing of electric motors when they are in reserve or on conservation in order to identify and eliminate deviations from the normal state;

Monitoring the health of measuring systems and measuring instruments, including their calibration and other work to maintain the good condition of electric motors;

10.3. At each power plant:

Responsible performers of maintenance work are appointed or an agreement is concluded with a contractor to perform these works;

A control system is being introduced to monitor the timely implementation and volume of work performed during maintenance;

Maintenance logs (operational logs) are drawn up, in which information about the work performed, deadlines and performers must be entered.

10.5. The type of repair of electric motors is determined by the type of repair of the main equipment, but may differ from it and be determined by the power plant, based on local conditions.

10.6. Overhaul of electric motors, as a rule, is carried out simultaneously with the repair of the mechanism. Combining the timing of repairs of electric motors with mechanisms is advisable in terms of reducing labor costs for work related to alignment, preparation of the unit’s workplace, etc.

10.8. Before the electric motor is taken out for repair, all preparatory work must be completed:

Long-term and annual plans for preparation for repairs have been developed;

A statement of planned work on the repair of electric motors provided for in the annual plan has been prepared;

Technical documentation for modernization or reconstruction work was compiled and approved;

The necessary materials, tools and equipment have been prepared;

Lifting mechanisms and rigging devices were brought into compliance with the rules of Gosgortekhnadzor;

The necessary spare parts have been prepared;

Fire prevention and safety measures have been completed.

10.9. The start of repair of the electric motor is considered to be the time of withdrawal for repair, established by the shift supervisor of the power plant,

10.10. Before stopping the electric motor for repairs while it is operating under load, operational measurements of electric motor parameters and an assessment of the current condition of the engine and its supporting systems are carried out, which are entered into the list of the main parameters of the technical condition of the electric motor, and equipment and service areas are also cleaned.

10.11. During routine repairs, the following work is performed:

Cleaning and blowing with compressed air;

Checking the air gaps between the stator and rotor;

Measuring clearances in plain bearings;

Inspection of the terminal box and contact connections;

Inspection of the bearing assembly, replacement or addition of: strokes.

10.12. The scope of overhaul of an electric motor according to the standard nomenclature includes the following work:

10.12.1. DC motors:

Pre-repair measurements and tests , defective assembly;

Dismantling from the installation site and transportation to the workshop;

Examination air gaps between the armature and the poles;

Disassembly electric motor;

Cleaning and blowing with compressed air, as well as using detergents;

Defect wrapped anchor;

Groove and continuation of the commutator, checking the quality of soldering of the armature winding to the commutator;

Defects of the traverse, revision of brush holders, replacement of electric brushes;

Defects of the magnetic system and repair of coils of the main and additional poles;

Defects of the frame and bearing shields;

Inspection and replacement of rolling bearings;

Electric motor assembly;

On-site installation, alignment with mechanism;

Measurements and tests after repair.

10.12.2 Asynchronous and synchronous electric motors:

Pre-repair measurements and tests, assembly defect detection;

Dismantling from the installation site and transportation to the workshop;

Checking the air gaps between the armature and the rotor, in plain bearings;

Complete disassembly with rotor removal (on site or in the workshop);

Inspection and cleaning of all parts and components;

Checking the compaction density of the stator active steel;

Inspection of welds and fasteners;

Checking the fastening of the stator winding in the slot and end parts;

Inspection of connections, stator winding terminals and terminal box;

Checking the fastening of the active steel of the rotor, blades and fan hub;

Inspection of the squirrel cage, fans and rotor bandage units;

Checking the serviceability of the squirrel-cage rotor rods and their tight fit in the groove;

Checking the fastening of poles, pole windings and interpolar connections of synchronous electric motors;

Checking the integrity of the damper (starting) winding;

Defects of slip rings with their grooving and grinding, checking the condition of traverses, brush holders, replacing defective and worn electric brushes;

Checking the fastening of balancing weights; replacement of lubricant and repair of bearings;

Defects and repairs of the thrust bearing (disassembling and cleaning the oil pan, removing the segments and their supports; checking the condition of fasteners and welds, cups of support bolts of the segment stops; checking the condition of the mirror surface of the disk, the insulating gasket and the tightness of its fit on the thrust bearing bushing; checking the segments and their supports, scraping them on the surface plate; installing segments and adjusting the load on the segments; replacing sealing elements, assembling the oil pan and sealing it);

Inspection of the cooling system (dismantling of the air cooler, oil cooler, their disassembly, cleaning and washing, replacement of gaskets and assembly; hydraulic tests and elimination of detected defects; installation of the oil cooler and its pressure testing with the system; inspection, high-pressure water testing of the air cooler and heat exchanger of the water cooling system of the AB (2AB) electric motor) -8000/6000, carrying out hydraulic tests of the water supply units of the rotor winding and the stator core of these electric motors);

Stator painting;

Electric motor assembly;

Electrical measurements and tests after repair.

10.13. After stopping the electric motor for repairs, electrical workshop personnel must:

Carry out all shutdowns to ensure safe working conditions;

Issue a work permit to repair the electric motor;

Establish the working hours of support workers (warehouses, laboratories, cranes, etc.).

10.14. During the repair process, the management personnel of the electrical shop must:

Carry out incoming quality control of used materials and spare parts;

Conduct operational quality control of repair work performed;

Check compliance with technological discipline (compliance with the requirements of technological documentation, the quality of the devices and tools used).

10.15. During a major overhaul of an electric motor, its components may be reconstructed in order to eliminate deficiencies identified during operation, as well as special work related to the repair or replacement of individual components. Changing the dimensions of parts, replacing components with products of a different type must be agreed with the electric motor manufacturer.

10.16. Special work related to the repair of the stator rotor windings, their partial or complete replacement, the repair of rotor bandage units and reconstruction, are usually carried out by a repair company.

10.19. Information about repairs must be entered into the documentation of the electric motor no later than 10 days after completion of the repair.

10.20. The suitability of the electric motor for operation is determined on the basis of the test results carried out in accordance with the requirements of chapters 4 and 5 of the current " Scope and standards of testing of electrical equipment"and based on the totality of all tests and inspections performed.

11 Safety precautions when servicing electric motors. Fire safety.

11.1. The basis for the safe operation of electric motors is compliance with the requirements of the current PTE, PTB, PPB, factory instructions for specific types of machines, compliance with permissible operating conditions (in terms of load, heating, vibration, lubrication, etc.) and technical maintenance (inspections, repairs, preventive tests) .

11.2. Operational and maintenance of electric motors must be carried out by persons who have undergone training, instruction and special training in studying the principles of operation, design, layout and maintenance methods of electric motors, who have acquired skills and experience in practical work, who have passed exams on knowledge of the rules of technical operation, safety regulations, job and local operating instructions assigned equipment.

11.3. Repair and restoration work on a specific electric motor must be carried out, as a rule, with the unit stopped, by issuing a work permit.

Admission of repair crews to the work site is carried out by the power plant duty personnel.

11.5. The winding terminals and cable funnels of electric motors must be covered with guards, the removal of which requires unscrewing nuts or bolts. It is not allowed to remove these guards while the electric motor is running.

11.6. Rotating parts of electric motors and parts connecting electric motors to mechanisms (clutches, pulleys) must have guards against accidental contact.

11.7. For a running two-speed motor, the unused stator winding and the cable supplying it must be considered live.

11.8. When working simultaneously on the mechanism and the electric motor, the coupling must be disengaged. Disengagement of the clutch must be carried out by repair personnel in accordance with the procedure for repairing the rotating mechanism.

11.9. Before starting work on the electric motor driving the pump or draft mechanism, measures must be taken to prevent rotation of the electric motor from the mechanism side. Such measures are closing the corresponding valves or gates, locking their steering wheels using chains or other devices and devices. Posters “Do not open! People are working" and "Don't turn it on! People are working”, prohibiting the supply of voltage and the operation of shut-off valves, and at the place of work there is a safety sign “Work here!”

The supply of operating voltage to the electric motor until the work is completed (test switching on, testing the electric motor or its starting device) can be done after the removal of the team, the return of the work crew to the operating personnel and the removal of temporary fences, locking devices and posters.

The work contractor is obliged to warn the workers of his team about the supply of voltage.

Preparation of the workplace and admission of the team after trial activation is carried out as during the initial admission.

11.11. During the period of repair, it is prohibited to use fire-hazardous detergents to clean metal parts, assemblies and windings with thermosetting insulation from contamination.

11.12. It is prohibited to service electric motors in women's dresses, raincoats, coats and robes due to the possibility of getting caught in the rotating parts of the said clothing.

Work using face and eye protection, in buttoned-up overalls, being careful not to get caught in the rotating parts of the electric motor;

Use dielectric galoshes and carpets;

Do not touch the live parts of both poles or the live and grounding parts with your hands at the same time.

Rotor rings can only be ground on a rotating electric motor using pads made of insulating material.

11.14. The use of rubber, polyethylene and other gaskets made of soft and non-oil-resistant material for flange connections of oil pipelines of the electric motor lubrication system is prohibited.

11.15. It is prohibited to carry out work on the oil pipelines and equipment of the oil system during its operation, with the exception of replacing pressure gauges and adding oil.

11.16. Fire extinguishing in electric motors (after they have been de-energized) must be done with water, carbon dioxide or bromine-ethyl fire extinguishers.

It is not allowed to extinguish fires in electric motors with foam fire extinguishers or sand.

11.17. If a winding fire is detected inside the electric motor housing, it must be disconnected from the network, and the synchronous electric motor must be de-excited.

12 General instructions for drawing up local instructions.

12.2. The local instructions must include those sections and paragraphs of this Standard Instruction that relate to all the main issues of operation of electric motors installed at a given power plant in relation to local conditions.

12.3. The local operating instructions for electric motors should specify:

Permissible conditions and operating modes of electric motors;

Distribution of responsibilities for servicing electric motors between power plant departments;

The procedure for preparing for launch, the procedure for starting, stopping and maintenance during normal operation and in emergency modes;

Procedure for admission to inspection, repair and testing of electric motors;

Safety and fire safety requirements specific to a specific group of electric motors,

12.5. In the relevant paragraphs of the local instructions, all instructions for the modes, frequency of inspections and monitoring of the operation of electric motors must be given specifically for each type of electric motor in use. In addition, the frequency of measuring vibration of bearings of critical mechanisms must be established.

12.7. The instructions must be revised at least once every 3 years.

12.8. The local operating instructions for electric motors must be signed by the head of the electrical department and approved by the technical manager of the power plant.

12.9. The local operating instructions for electric motors should specify the list of emergency situations in accordance with local conditions.

12.10. The local instructions must contain a list of critical mechanisms approved by the technical manager of the power plant, the re-enablement of which, after being switched off by their protections, is permitted after an external inspection.

12.11. The local operating instructions for electric motors should contain a list of protections, interlocks and alarms.

Application

Typical malfunctions of electric motors and their elimination

p.p.	Signs abnormal phenomenon	Probable Causes
	When starting electric motorbuzzes and doesn't turn around	Break of one phase in the stator circuit (fuse blown, poor contact in the switch, etc.). Break or poor contact in the rotor circuit (broken or burnt out rods in the area of the short-circuit rings).	Using a megohmmeter, identify the circuit break and eliminate it.
			Identify cracks or breaks in the rods by measuring the magnetic leakage flux around the rotor circumference using VAF-85 (for the method, see EC No. E-11/61 or § 6.60 SDME-81) or in another way.
		The stator winding circuit is assembled incorrectly (“star” instead of “triangle”, one phase is turned out, etc.). Mechanical binding in the drive mechanism or motor	Check the polarity of the terminals (determine the beginnings and ends of each phase) and assemble the stator winding circuit according to the manufacturer’s instructions. Bring the unit out for repairs and remove the jamming
	Sparks and smoke appeared from the engine when starting or during operation.	The rotor touching the stator due to a foreign object getting into the air gap, excessive wear of the bearings..	Bring the unit out for repairs to eliminate the defect.
		The rod of the short-circuited rotor winding has broken.	Take the engine out for repairs.
		Interturn short circuit in the stator winding	Repair winding fault
	At start-up, overcurrent protection operates	Short circuit in the stator circuit (in the cable, in the stator winding, terminal box).	Inspect the entire circuit up to the switching device, measure the insulation resistance of the circuit elements. If a short circuit is detected, remove the connection for repair. Change the protection settings in accordance with the conditions of detuning from the starting mode of the electric motor. Repair the drive mechanism



		The protection tripping current is low or the overload time delay is short. Drive mechanism faulty






4	Increased vibration of bearings	The alignment of the engine with the drive mechanism is incorrect.	Align the motor with the drive mechanism.


		The rotor is out of balance and the coupling is unbalanced.	Balance the rotor. Remove the coupling and balance it separately from the rotor. Construct the foundation in accordance with factory installation requirements.


		Insufficient foundation rigidity.
		There are gaps between the engine feet and the foundation	Eliminate gaps with gaskets.
		The motor feet on the Drive side are not pinned and the disc springs are not installed on the foundation bolts on the side opposite to the drive.	Install the pins and disc springs.
		The coupling is faulty, there are defects in the gear coupling due to improper engagement and improper tooth processing. There is a misalignment between the coupling halves mounted on the shafts, one or both coupling halves are beating, the pins of the elastic-finger coupling are installed incorrectly or are worn out.	Repair or replace the gear coupling. Check the correct fit and runout of both coupling halves, check the installation of pins in the coupling halves. If necessary, eliminate increased runout of the coupling halves, correct the installation of the pins or replace them with new ones.
		The temperature of the oil entering the bearings with forced lubrication is too low	During engine operation, the incoming oil should have a temperature of 25-45°C
	When the engine is running, rhythmic oscillations of the stator are observed.	Loss of contact or turn short circuit in the rotor winding	Carry out inspection and necessary repairs to the rotor.
	Water leak from the air cooler, the sensor for monitoring the presence of water in the engine is triggered	Possible cracks in the cooling tube at the flaring site or weakening of the flaring	Remove water from the engine. Conduct hydraulic tests of the air cooler to determine the location of the leak. It is allowed to plug one defective tube on both sides with plugs. If there are more damaged tubes, replace the air cooler
	Water leak in the electric motor AB(2AV)-8000/6000 in the weld or in the “fitting rod” connection of the rotor	Formation of a fistula or fissure	Cut out the leak to a depth of 4 mm. Solder with PSr45 solder and PV209X flux. After filling the hole with solder, maintain it for 1 minute. heating the rod neck to reduce stress in the “nozzle-rod” connection.
	in the “rod-short-circuit ring” connection of the rotor	Same	Cut and remove the technological steel bushing, cut out a groove 5 mm deep around the rod. Solder with PSr45 solder and PV209X flux, maintaining the heating of the rod neck as it cools.
	through tubes inside the stator core segment	Cracks, fistulas	Exclude a segment from the diagram using a jumper. It is allowed to exclude up to two parallel branches, the distance between which must be at least three packets. In the two extreme branches from each end of the core, segments are not allowed to be excluded.
	V collector stator	Loose fittings.	Tighten the nuts and lock.
		Loosening of the rubber seals in the end caps.	Tighten flanges or replace rubber seals
		Damage to the welds on the manifold.	Weld the welds
		Contamination of mating sealing surfaces	Clean sealing surfaces thoroughly
	Increased leakage of cooling water through the rotor AB (2АВ)-8000/6000	Wear of the fluoroplastic seal	Replace bushing
	Overheating of the entire stator winding and active steel. Increased temperature of cooling air at the outlet of the cooler	Increasing the load more than permissible.	Reduce the load to rated and below.
		Increase in cooling water temperature above normal	Increase water flow above normal, but not more than twice (in this case, the pressure in the cooler should not exceed the maximum permissible).
		Reducing water consumption	Clean the cooler by removing both covers. Rinse the tubes with a 5% solution of hydrochloric acid and clean them with special brushes (“brush”).
		Clogging of the inter-tube space of the cooler	Inspect the filters, thoroughly blow out the interpipe space with compressed air
	Increasing the water temperature at the outlet of the rotor, stator AB (2АВ) -8000/6000	Clogged rotor or stator cooling path	Backwash with water at a temperature of 80-90°C. If the effect of this method is insignificant, use chemical reagents (5% hydrochloric acid solution and 5% chromic anhydride solution)
	There are no readings from one of the resistance thermal converters	Broken sensor or test wiring	Replace the defective converter, eliminate the break or put the reserve cable core into operation
	Excessive bearing heating	Insufficient oil supply to the bearings (lubrication ring seizes). Excess or lack of lubrication in rolling bearings.	Increase the oil supply to the bearings and eliminate the ring malfunction. Check the quantity and quality of lubricant. If necessary, wash and fill the bearing with the required amount of lubricant.
		Grease or oil is contaminated	Clean the oil chambers of the bearings and change the oil.
		The wrong brand of oil was used.
		Axial impact on the motor rotor from the driven mechanism.	Check the alignment and connection of the motor to the driven mechanism
		No rotor run-up	Check the presence of adjusting shims between the bearing housing and the shield on the side of the working end of the shaft.
		Increased rotor vibration	See paragraph of this table
		Increased rotor vibration	See paragraph of this table
	Oil leakage from bearings	Increased oil consumption through bearings.	Adjust oil consumption.
	Oil leakage from bearings	The drain is clogged oil line Insufficient sealing of the joints between the labyrinth seals and the bearing housing	Clean the oil drain line. Replace gaskets between labyrinth seals and bearing housing
	Reduced insulation resistance of the stator winding	The winding is dirty or damp	Disassemble the electric motor, blow with dry compressed air, wipe the winding with a cloth moistened with detergent, and dry the insulation
	Increased brush sparking	Insufficient force to press the brushes against the slip rings.	Adjust the pressing force of the brushes.
		Contamination or unevenness of the working surfaces of the slip rings.	Sand the working surface of the rings with fine sandpaper, remove dirt and deposits with a cloth moistened with alcohol. If necessary, sharpen and polish the rings.
		Brushes do not adhere well to slip rings	More carefully grind and grind the brushes to the rings

List of used literature

Rules for the technical operation of power plants and networks of the Russian Federation. -M.: SPO ORGRES, 2003.

SO153-34.03.150-2003. Interindustry rules for labor protection (safety rules) during the operation of electrical installations M.: Publishing House NC ENAS, 2003.

SO 34.03.201-97 (RD34.03.201-97). Safety rules for the operation of thermal and mechanical equipment of power plants and heating networks. - M.: Publishing House NC ENAS, 2001.

SO 34.03.301-00 (RD153-34.0-03.301-00). Fire safety rules for energy enterprises. - M.: CJSC "Energy Technologies", 2000.

SO34.04.181-2003. Rules for organizing maintenance and repair of equipment, buildings and structures of power plants and networks, M., 2004.

Electrical insulation systems. Heat resistance assessment and classification.

GOST9630-80. Three-phase asynchronous motors with voltage over 1000V. General technical conditions.

GOSTR 51757-2001. Three-phase asynchronous motors with voltage over 1000V for auxiliary mechanisms of thermal power plants. General technical conditions.

GOST 17494-87. Electric rotating machines. Classification of degrees of protection provided by the shells of rotating electrical machines. Notation. Test methods.

GOST 12969-67. Plates for machines and devices. Technical requirements.

GOST 12971-67. Rectangular plates for machines and devices. Dimensions.