• Author / Uploaded
• Tshering Peljor

• Categories
• Rodamiento (Mecánico)
• Conector eléctrico
• Aislador (Electricidad)
• Resistencia Eléctrica y Conductancia
• Motores

Citation preview

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

NUCLEAR POWER CORPORATION (A Govt. of India Enterprise)

RAJASTHAN ATOMIC POWER STATION – 3&4 ELECTRICAL MAINTENANCE UNIT

MAINTENANCE PROCEDURE FOR ELECTRICAL MOTORS (PROCEDURE NO. R-3&4 – EMP–50100–01)

Prepared by : (C.P. Sharma) SO/E (EM) Checked by & Reviewed By :

Approved by :

(Vivek Jain) SME (E) Revision No. Rev –0

Rev. No. 0 Feb. 2002

Date

Prepared/Revised By

March, 2002

-1-

(P.K.Datta) MS Reviewed By

Approved By

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

INDEX S No. 0.0 1.0 1.1 1.2 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.2.9 1.3 1.3. 1.3.2 1.3.3. 1.4 1.5 2.0 2.1 2.2 2.2.1 2.2.2 2.2.3 2.2.4 2.2.5 2.2.6 2.2.7 2.2.8 2.2.9 2.2.10 2.2.11 2.2.11.1 2.2.11.2 2.3 2.3.1 2.3.2 Rev. No. 0 Feb. 2002

TITLE Title Scope Category of Equipment/Maintenance Criteria General Description General Stator Rotor & Bearings Lubrications Bearing replacement Drying out End shield Fan & fan guards Terminal box Technical Details 1 Applicable Standards Quantity of Grease Quantity of Grease List of Equipment sub Assemblies List of References and Drawing Maintenance Procedure Condition Monitoring Preventive Maintenance Frequency of Preventive Maintenance Pre-requisite Tools/Instruments Required Consumable & spare requirement Man Power Required Expected time of completion Initial observation before starting the job Safety instruction and precautions Dismantling procedure Test on Equipment Return to service Re-assembly No load run Break down Maintenance Frequency of over hauling Pre-requisite -2-

PAGE No. 4 4 5 5 5 6 6 7 7 8 8 9 9 9 9 9 10 10 11 11 11 11 11 11 11 12 12 12 12 12 12 13 13 13 13 14 15 15

MAINTENANCE PROCEDURE S No. 2.3.3 2.3.4 2.3.5 2.3.6 2.3.7 2.3.8 2.3.9 2.3.10 2.3.11 3.0 4.0

PAGE No.

TITLE Tools and special instrument Man Power Expected time of completion Consumables and spare requirement Initial observation before starting the job Safety instruction and precautions Dismantling procedure Test on equipment Return to serve Trouble shooting Annexure Annexure-1 Annexure-2 Annexure-3 Annexure-4 Annexure-5

Rev. No. 0 Feb. 2002

R-3&4-EMP-50100-01

Preventive Maintenance Check list Preventive Maintenance Check list Preventive Maintenance Check list Preventive Maintenance Check list Preventive Maintenance Check list

-3-

EMP-50100/01/PM/01 EMP-50100/01/BM/02 EMP-50100/01/PM/03 EMP-50100/01/BM/04 EMP-50100/01/BM/05

15 15 15 15 15 15 15 18 15 16 18 19 23 27 30 34

MAINTENANCE PROCEDURE 0.0

R-3&4-EMP-50100-01

TITLE : Maintenance procedure for Electrical Motors.

1.1

SCOPE: Approximately 2000 Nos. of LT / HT motor are installed alongwith pumps & fans in various systems in the plant. They are fed from HT / LT switchgears and MCC’s, depending upon size of the motor and are reasonably protected against various ‘expected’ faults. In order to ensure smooth operation of motors and also to prevent development or propagation of any deficiencies in the motors, they are being given preventive maintenance regularly. Still, if some motor breakdown, then it get rewinded / repaired. The scope of this manual covers maintenance requirements and procedural aspects of preventive & breakdown maintenance checks to be performed on motors. Apart from this manual, specific references is to be made to the relevant maintenance instructions of the respective manufacturer. The following make & sizes of motors are installed at RAPS-3&4 :i) HT (6.6 KV) Motors - M/s Kirloskar / NGEF / BHEL make of size above 200 KW to 2800 KW. ii) LT (415V) Motor - M/s Kirloskar / NGEF / SIEMENS/ GEC / BHARAT BIJLEE / CROMPTON GREAVES / ABB of sizes from fractional KW to 200 KW

Details of important loads is as follows :-

S.No. 1 2 3 4

Description

5 6 7 8 9 10 11

Primary circulating pump motor Boiler feed pump motor Condense extraction pump motor Active low pressure process water pump motor Chiller motor Condenser cooling water pump motor Primary feed pump motor Plant water pump motor HP Aux. Oil pump motor Active HP process water pump motor Moderator pump motor

12

Shut down cooling pump motor

13

Fueling machine supply pump motor

Rev. No. 0 Feb. 2002

-4-

Make

KW

Volt

NGEF BHEL KEC NGEF

2800 1450 720 335

6600 6600 6600 6600

No. of motors (both Unit) 8 6 4 6

NGEF KEC NGEF KEC BHEL NGEF Crompton Greaves Crompton Greaves NGEF

435 965 350 720 375 170 132

6600 6600 6600 6600 6600 415 415

3 6 4 2 2 8 10

80

415

4

93

415

4

MAINTENANCE PROCEDURE S.No. 14 15 16 17 18 19

1.1

Description Active process cooling water pump Auxiliary boiler feed pump motor Compressor motor Fire water pump motor ECCS pump motor Exhaust fan SFB, RAB, RB

R-3&4-EMP-50100-01

Make

KW

Volt

NGEF NGEF KEC NGEF NGEF GEC Alstom

160 130 140 100 130 125

415 415 415 415 415 415

No. of motors (both Unit) 8 4 6 2 8 3

CATEGORY OF EQUIPMENT / MAINTENANCE CRITERIA: Motors covered in this manual will fall under all categories of station equipment classification i.e. Category – A, B, C or D, depending upon the respective process system. Frequency of maintenance of these motors, depending upon their usage, application, availability of shutdown accessibility to location etc., shall be i)

Preventive Maintenance : Yearly- for safety related loads ( Cat. A) Two yearly- for non-safety related (Cat. B,C &D)

ii)

Breakdown Maintenance : Need based

The above suggestive schedules may have to be reviewed for better performance depending upon factors like Running Time of the motor, maintenance intervals and lubrications intervals etc., as recommended by the respective manufacturer.

1.2

GENERAL DESCRIPTION :

1.2.1

GENERAL i) ii) iii)

iv) v) vi)

viii) ix) x) xi) xii) xiii)

Rev. No. 0 Feb. 2002

Ensure that the motor is isolated from the power supply source and physically confirm at the switchgear / MCC end Request MMU to take pre-maintenance alignment values, if required by them. Inspect the power terminal box for any abnormality, like loose connections, loosening of cable lugs, de-colorization of cables due to overheating or any other sign of overheating and disconnect the cable. Insulate the cable lugs with insulation tape. Note down the RYB sequence of terminal connections before disconnecting the cable. Do the disconnection of space heater, if provided, in a similar way, Ensure handling equipment / manpower are ready for shifting the motor to maintenance area. Request MMU to de-couple the load, Loosen the foundation bolts of the motor and remove it away from the platform. If any foundation packing material like copper shims or vibration arresting pads are provided, mark them with proper identification marks (which would help in relocationg them at the right place during reinstallation) and secure them at a safe place, vii) Shift the motor to the motor maintenance area or shop as required. Check pre-maintenance IR values of winding, Record the pre-maintenance value of winding resistance / inductance. Record space heater resistance and IR values, if applicable. Record the RTD / Thermistor values, if applicable. Prior to dismantling, make match marking on the stator body and the end shields on both sides, to avoid human error during reassembly, Remove the fan cover and subsequently the fan,

-5-

MAINTENANCE PROCEDURE xiv) xv) xvi)

xvii)

xvii)

1.2.2

Remove the coupling pully and secure it along with the key safely. Loosen the end shield mounting bolts diagonally and gradually, Use suitable pullers, wooden block or mallet while dismantling or assembling. Avoid using hammers in the process as these may damage end shield / motor body which are made of Cast Iron, Remove both the end shields. For large motors, suitable support should be provided to the shaft (while the end shields are being dismantled) so as to protect the shaft from getting bent or deformed, Separate the end shields, rotor and the stator bodies

STATOR i) ii) iii) iv)

v) vi)

vii) viii) ix) x) xi)

1.2.3

R-3&4-EMP-50100-01

Inspect the stator winding closely for any physical damage to the winding insulation / coils/ overhangs, Examine the inner surface of the stator slots for any abrasive marks, damage to the wedges etc., Ensure that winding overhangs are safely secured, Ensure terminal connections of the windings are healthy and tight. Take care to tighten the terminal stud nuts, lock nuts etc., and ensure flat and spring washers are positioned appropriately, Clean the stator core, windings, frames etc., with a suitable , lint free cloth etc., Measure resistance / inductance of the windings with the help of Motor checker and ensure these are balanced. If severe non-uniformity is found, locate the faulty winding and the location of fault by using a Growler. Rectify the fault if possible locally. Otherwise the motor must be sent for repair / rewinding and a spare motor should be put on the system, Check connection tightness of space heater connections and measure the resistance and insulation values, Check RTD resistance, if applicable and record their values along with ambient temperature at the time of testing, ix) Measure insulation resistance value of the winding and ensure it is more than 5 M ohm (when the stator is cold), If the insulation resistance is found to be below 2 M ohm, the motor should be dried out before returning to service. The methods of drying out are explained vide 1.2.6 of this manual. If “Rotation Arrow” plate is provided, ensure it is visible and clear and does not lead to any illusion.

ROTOR & BEARINGS i)

Remove the dirt, dust from rotor by using brush cloth etc., or by compressed air / vacuum cleaner. Subsequently clean it with kerosene thoroughly.

ii)

Inspect the cage rotor bars for any cracks or slackening,

iii)

Ensure shorting rings at both the ends of the rotor are healthy and no sign of cracks is present.

iv)

Inspect the bearings carefully and ensure they are free from any defect (If found defective, replace both the bearings as per procedure given in para 1.2.5).

v)

If the old grease is found to be dirty or deteriorated, greasing should be done afresh, as per the procedure laid down in 1.2.4 of this manual. Do the lubrication just before reassembly.

vi)

Inspect the coupling key/ key way for any defect or damage,

vii)

Whenever bearings are replaced, ensure inners of bearings covers are in place before installing new bearings on to the shaft. Follow procedures laid down in 1.2.5 of this manual during bearings replacement.

Rev. No. 0 Feb. 2002

-6-

MAINTENANCE PROCEDURE 1.2.4

R-3&4-EMP-50100-01

LUBRICATION Normally the original grease need not be removed unless it has become dirty or has deteriorated. The hands must be perfectly clean and smeared with good quality mineral oil before any bearing is handled. A small quantity of old grease will unavoidably be left in the bearings (when old grease is wiped out from the bearing) and if this is clean and in good condition it should be left rather than washed out with petrol. A good bearing can be ruined by rotating in the absence of lubricant. When washing out is essential, it should be carried out in a bath of clean benzene or petrol to which a small quantity of lubricating oil has been added. Before bearing is packed with grease, a few drops of clean lubricating oil should be introduced into the bearing. Never over-grease any bearing which may lead to overheating and spillage. Lithium based multipurpose grease conforming to grade 3 of IS-1002-1956 amended up to date is recommended for all rotating machines fitted with anti-friction bearings. The approved grease among others is Castrol Ball Bearings Grease AP-3. The safe operating temperature for the above grease is 25°C to 120°C (approx. value)

1.2.5

BEARING REPLACEMENT 1)

Removal of Bearings The bearings along with its housing should be removed from the shaft using bearing puller, otherwise the bearing may get damaged. The endshied and the external bearing cap must first be removed, and then the small retaining screw in the split locking collar must be loosened, after which the collar can be unscrewed. If any difficulty is experienced, widen the split in the locking collar with say a screw-driver. The tapped holes in the housing may be used for fixing the withdrawing gear, studs and equal pressure must be put on each nut, otherwise the internal bearing cap may be distorted and damaged. When dismantling the inner ring of a ball bearing from the shaft on no account must the bearing be knocked off the shaft by hitting the outer ring of the bearing. The housing and the bearing may then be separated without any difficulty as a push fit is employed.

2)

Cleaning of Bearing The bearing should be washed to remove all traces of old grease and dirt or foreign matter that may have crept in. The use of goods quality solvent or a mixture of eight parts of white spirit to one part of light grade machine oil is recommended for washing. Where a solvent is used for washing, all the parts should be dipped in good quality light machine oil after the washing is completed. If not immediately re-used, protect the bearing with grease paper wrapping.

3)

Assembly of Bearing Ensure that all the parts are handled carefully to avoid entry of foreign particles. A bearing should not be removed from its housing until it is required for use. After cleaning the housing it should be smeared lightly with the specified grade of grease. In the case of roller bearing lay the housing flat on a clean level surface and insert the bearing outer ring by applying even pressure to the ring. Ensure that the bearing remains “Square” in the housing through out this operation. It may be necessary to tap the outer ring lightly into the housing in the final stage.

Rev. No. 0 Feb. 2002

-7-

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

Next slip the inner bearing cap correctly over the shaft after a small quantity of grease has been applied inside it. The inner ring of the bearing may now be fitted over the shaft by heating the bearing in a mineral oil to a temperature not exceeding 100°C to enable easy mounting. Fit the split locking collar correctly on the shaft to clamp the inner ring, close the split on the collar by a gently blow on the same, and tighten the remaining screw firmly. Re-lubricate all parts as detailed in Appendix-2. Assemble the endshield containing the outer ring of the bearing and fasten to the inner bearing cap. Rotate the bearing housing by hand in both directions to check if the running is smooth. If this is the case fit the outer bearing cap firmly to the bearing housing. A small gap MUST be visible between the flange of the external bearing cap and the housing this gap confirms that the outer ring of the bearings is firmly clamped to prevent its creep during operation.

1.2.6

DRYING OUT A convenient method of “Drying out” is to block the rotor so that it can’t rotate and apply a very low voltage of about 10% of the rated value to the stator terminals. The heat generated in the winding is not easily dissipated and one part of the winding may be exceedingly hot before another part had time to expel the moisture. This may be deviated to some extent by taking every precaution to exclude draughts for the exposed parts of the winding. Second method of drying out is to keep the motor in an electrical oven. But the temperature shall not be allowed to exceed 60°C. Other options are (i) blowing of hot air (ii) using electric radiators (iii) placing of carbon filament lamps inside the m/c. When placing hot bulb, care shall be taken that it is not in contact with the windings. If it is not possible to reach sufficient high temperature the ventilation may be reduced by covering the stator with a tarpaulin. Whichever of the above method of drying out is adopted the heating shall be continuous and shall be carefully monitored to ensure that it does not attain a temperature sufficiently high to damage the insulation. The maximum safe temperature of the windings measured by thermometer is 90°C. At the same time the temperature should not be allowed to fall too low as otherwise re-absorption of moisture would take place. The insulation resistance will be found to drop considerably as the motor warms up will reach the minimum and then remain constant for sometime depending upon the dampness of the machine and as the drying progresses the insulation resistance will gradually rise. The drying out shall be continued as long as the insulation resistance rises or until a sufficiently high value has been reached which should not be less than 2M ohm by 500 volts megger (for LT motors). During the drying out period, readings of temperature and insulation resistance shall be taken at least once an hour in order to see how the drying out is progressing. The temperature of the motor shall be kept as constant as possible, otherwise the insulation resistance readings may be misleading. After drying out, air drying varnish should be applied by brush on the winding surfaces only and this should be applied when winding is in hot condition to prevent absorption of moisture. The length of drying time depends on the amo unt of dampness but in any case it should be at least six hours.

1.2.7

END SHIELDS i) ii)

Rev. No. 0 Feb. 2002

Clean the end shields thoroughly Inspect the bearing housings for any damage or any abrasive mark. The bearings should fit tight in the housing.

-8-

MAINTENANCE PROCEDURE iii)

If any grease- filling holes are provided, ensure these are clean and not choked. Clean them thoroughly Also ensure air gap inspection holes (closed with threaded metal plugs), if any provided are clean.

iv)

1.2.8

FAN & FAN GUARD i) ii) iii) iv)

1.2.9

R-3&4-EMP-50100-01

Clean the fan and fan guard thoroughly. Ensure balancing weights, if any, provided on the fan are intact Inspect the fan closely for any crack. Ensure key/keyway/locking screw of the fan is healthy.

TERMINAL BOX i) ii) iii)

Clean the terminal box thoroughly, Inspect the lugs for de-colorization, lug afresh, if conductor strand found burnt, Inspect the lead coming out from stator, for any damage to the conductor, If so, it must be repaired by strengthening insulation or by re-lugging (for LT motors only) Check terminals to be intact, Check glanding to be perfect, For HT motors, check condition of HT kit to be OK, Check tightness of cable connections.

iv) v) vi) vii)

1.3

TECHNICAL DETAILS :

1.3.1

APPLICABLE STANDARDS All the motor maintenance activities and post-maintenance testing shall conform to the following Indian standards as per the latest revision : i) ii) iii) iv) v) vi) vii) viii)

1.3.2

Performance & Testing Insulation Method of cooling Type of construction & mounting Terminal markings Vibration level & measurement Noise level Testing

-

IS : 325 IS : 1271 IS : 6362 IS : 2253 IS : 4728 IS : 4729 IS : 6098 IS : 4029

QUANTITY OF GREASE Quantity of grease required per bearing and the re-greasing intervals for normal motor is as per the following table : Amount of grease in cm3

Type

Rev. No. 0 Feb. 2002

AM

AJ

4,6,8, & 10 pole

132

-

12

160

160

16

-9-

To be injected after running hours 2 pole

4 pole

6 & 8 pole

1500

1500

2000

MAINTENANCE PROCEDURE Amount of grease in cm3

Type AM

AJ

4,6,8, & 10 pole

180

180

20

200

200

20

225

225

20

35

250

250

20

35

280

280

20

35

315

315

25

40

355

355

25

40

R-3&4-EMP-50100-01

To be injected after running hours 2 pole

4 pole

6 & 8 pole

750

1200

1500

For motors used in chemical industries, refineries and other industries where acid, alkali and saline atmosphere are predominant and for motors with IP 55 protection the re-greasing interval should be reduced by 20% 1.3.3

QUANTITY OF GREASE Grease Qty. (in Grams)

3000 RPM

1500 RPM and below

6313 6314 6315 6316 6318 6319

20 25 30 35 35 40

1500 1000 1000 1000 1000

4000 2500 2500 2500 -

N315 N316

30 30

N318 N319 N221 N321

35 40 40 50

1000 1000 1000 1000 -

2500 2500 2500 2500 2500

NOTE

1.4

Re-greasing interval

Bearing Size

:

ALL TWO POLE MOTORS SHALL HAVE C-3 CLEARANCE BEARINGS. FOR VH SERIES MOTORS, TOP BEARING SHALL HAVE SPHERICAL ROLLER THRUST BEARING, WHICH IS OIL LUBRICATED.

LIST OF EQUIPMENT SUB-ASSEMBLIES:

This maintenance procedure shall be applicable to all the electrical motors in various systems, along with their corresponding power cable. The following are various parts / sub-assembly of motor – i) ii) iii)

Rev. No. 0 Feb. 2002

Rotor Stator Bearings

- 10 -

MAINTENANCE PROCEDURE iv) v) vi) vii) viii) ix) x) xi)

1.5

End shield Terminal box Pulley Space heater (for motor of rating 30 KW & above) Space heater terminal box (for motor of rating 30 KW & above) Cable end alongwith gland and termination kit (for HT cable only) Cable supporting structure. Fan & fan guard.

LIST OF REFERENCES AND DRAWINGS: 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) 15)

2.0

R-3&4-EMP-50100-01

Load schedule User hand book for induction motors (Kirloskar) MI for PHT motor MI for BFP motor MI for CEP motor MI for main chiller unit MI for plant water pump motor MI for moderator pump motor MI for S/D cooling pump motor MI for Air compressor (Kirloskar) MI for PFP motor MI for CCW motor MI for NAPW motor MI for Fire water motor MI for moderator motor.

– – – – -

(EM-855) (EM –556) (EM –545) (EM –584) (EM –194) (EM – 635) (EM – 444) (EM – 672) (EM – 190) (MM - 1241) (Central Doc cell - 2748) (MM - 351) (MM - 691) (EM-1208)

MAINTENANCE PROCEDURE: The objective of maintenance is to ensure smooth operation of all the electrical motors.

2.1

CONDITION MONITORING: Not Applicable

2.2

PREVENTIVE MAINTENANCE:

2.2.1

Frequency of Preventive Maintenance: Yearly – for safety related equipment (Cat. A) Yearly – for non-safety related equipment (Cat B,C &D)

2.2.2

Pre-requisite: 1) Work permit should be taken. 2) Proper isolation has been provided. 3) Proper tools & equipment are available. 4) Consumable are available

2.2.3

Tools & Special Instruments: a) Megger ( 500 V for LT motors & 5 KV for HT motors) b) Motor checker c) Screw Driver d) Spanner e) Wire brush

Rev. No. 0 Feb. 2002

- 11 -

MAINTENANCE PROCEDURE 2.2.4

2.2.5

R-3&4-EMP-50100-01

Consumables and Spare Requirement: i) ii) iii) iv) v)

Cleaning agent Lubricant Contact grease (Electrically conducting) Winding / Core cleaner Rust remover (Nut bolts)

– – – – –

vi) vii)

Paint & varnish remover Varnish

– –

viii) ix)

For pasting / sticking gasket Repairs of stator winding (Patch-up work)

– –

CRC, OKS Sentinel synthetic lubricant “ Servogem” contact gelly Lotoxane (Arnold make) Rustolene (M/s Hard Castle & Ward Mfg. Co.Ltd.) Action 100 (M/s Gunjan Organics Pvt. Ltd.) “Crown”Red insulating varnish (M/s Stanvac chemicals (I) Ltd.) LOCTITE (M/s Loctite India Pvt. Ltd.) Epoxy gelcoat (Red) (Dr. Beck+ co.)

Man Power: Supervisor – 1 Technician – 2

2.2.6

Expected Time of Completion: 8 Hour.

2.2.7

Initial Observation Before Starting the Job: 1) 2) 3)

2.2.8

Safety Instruction and Precaution: 1) 2) 3) 4) 5)

2.2.9

Check the motor terminals & lugs for any over heating marks. Check the motor internal leads and cable leads for any crack / damage of insulation. Any abnormality in motor.

Avoid using slide wrench, Never use plier for opening a bolt / nut. Put proper marking on TB cover plate before opening. The plate may be too heavy to be handled by one person. All nut-bolts should be kept at one place, duly segregated size wise. Discharge cable before touching the terminals, as the same may be having static charge. While pulling rotor out from the motor, no damage to starter core/ winding should be ensured.

Dismantling Procedure: The sequence of dismantling motors is given below : 1) Before dismantling any machine, obtain “permit to work” from authorities. 2) If required, arrange a crane of sufficient capacity and height to lift off the motor and taking to maintenance shop, 3) Disconnect supply cables at the terminal box, detatch terminal box from cable spreading box and support the latter against falling, 4) Uncouple the motor from the driven machine, 5) Unfasten the foundation bolts or nuts and lift the motor for removed to maintenance shop or elsewhere for further disassembly. 6) Collect all the hardware like bolts/nuts, shims used below machine foot (for alignment) etc., and keep them separately. Do not mix them with ordinary hardware. 7) Remove the grease extractors if fitted to bearings and remove all the old grease collected in it.

Rev. No. 0 Feb. 2002

- 12 -

MAINTENANCE PROCEDURE 8)

R-3&4-EMP-50100-01

The dowel pins used for location of motor should be removed carefully. The dowel pins should be stored more carefully as these are required to ensure correct repositioning of motor after overhauling. Remove the external fan cover and fan where fitted. Remove any cowls, canopies or other fitments fitted on the endshields. In the case of slipring motor, remove the slipring cover and dismantle the brushgear carefully. The slipring stud nuts are all the brass, store them carefully away from other steel hardware. Remove the endshields after the removal of fastening bolts, making use of the endshields removing screws provided. For bigger size of motors remove the rotor with the help of a crane. Ensure that this is done very carefully and that the rotor does not touch the stator winding overhand during this process to prevent damage to the windings. Remove any accumulated dust or dirt with a dry soft brush or bellows. Remove the outer bearing caps and the bearing housing at both ends and remove also all old grease from bearings to expose them.

9) 10) 11) 12) 13)

14) 15)

Note : Where the bearings are oil lubricated, drain the oil before removing the bearing housing or endshield.

2.2.10 Test on Equipment: Preventive maintenance test are to be carried out as per the following check lists : 1) EMP/50100/01/PM/01 - PM of HT Motor 2) EMP/50100/01/BM/02 - BM of HT Motor 3) EMP/50100/01/PM/03 - PM of LT Motor 4) EMP/50100/01/BM/04 - BM of LT Motor

2.2.11 Return to Service: 2.2.11.1 Re-assembly – 1.

2.2.11.2

2.

After the assembly is completed, check the concentricity of the air gap through the air gap inspection holes, and close these with the plugs provided. Ensure that the rotor can rotate freely. Any difficulty in rotating the rotor or any unusual noise should be taken as sign of interference between stationary and mo ving parts. In such a case investigate and eliminate the cause of the trouble.

3.

Check the insulation resistance again.

4.

Realign the machine with the load but do not couple.

5.

Reconnect the machine to the supply cable acording to the terminal connection diagram fixed inside the terminal box cover. Ensure that the supply cable sockets make intimate contact with the motor cable sockets in the case of low voltage terminal box, there must be NO nut or washer of any kind between the sockets.

No load Run : 1)

Rev. No. 0 Feb. 2002

The procedure is practically the reverse of that followed for dismantling.

A transient kick start may be given to ascertain the direction of rotation. If it is incorrect, stop the motor and inter change the connections to any two phases in the terminal box. Re-start the motor and examine carefully for any evidence of unusual sound, vibration, electrical or mechanical fault conditions and undue temperature rise of the bearings. Run the motor in uncoupled

- 13 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

conditions and check the vibration level. Vibration measured on no load must be within 25 microns (peak to peak). Then run the motor in uncoupled condition with half-coupling pulley mounted on the motor shaft extension and check the vibration level. This vibration shall also be within 25 microns (peak to peak). Measure the no load current, though out its No Load run at a fixed regular intervals. The No Load current should remain constant and as thumb rule would be equal or less than 40% of full load current of the motor. Record the observations as per PM check list. No Load run for big motor shall preferably to done for a period till its bearing temp. stop rising further. This period may be 4 to 8 Hrs. 2)

Couple the motor with the driven machine. Check that the driven machine is not loaded but see above point-1 for vertical high thrust motors. Start the motor and examine carefully for any evidence to unusual sound, vibration, electrical or mechanical fault. If no abnormality is observed, run the motor for a few hours. Check the bearing and the body temperatures.

3)

Load the driven machine. As far as possible increase the loading gradually. Allow the motor to run under full load conditions for a few hours, provided there is no indication of fault any where. During this period note the current drawn by the motor and the speed and check that the current does not exceed the rated value as stated on the motor name plate. If it does, reduce the load or stop the motor and determine the cause. It could be that the voltage is lower than that specified or the motor may have been overloaded. The motor should not be restarted until the cause of this problem has been eliminated. Check the vibration level in coupled condition on load. The increase in vibration level on load over that measured on no-load (in uncoupled condition) should not exceed the value given in the following table. Allowable increase in vibration amplitude (peak to peak in mm) when the motor is coupled to the load and tested over the vibration amplitude of motor tested in uncoupled condition. Synchronour speed re/min

2.3

Increase in vibration amplitude (peak to peak) microns

3600

5

3000

6

1800

9

1500

11

1200

12

1000

14

900

15

750

16

720

16

600

18

500

20

428

25

375

26

BREAK DOWN MAINTENANCE : Despite all precautions and preventive maintenance, if the motor insulation fails, then the motor is taken out for breakdown maintenance.

Rev. No. 0 Feb. 2002

- 14 -

MAINTENANCE PROCEDURE 2.3.1

R-3&4-EMP-50100-01

Frequency : As and when required.

2.3.2

Pre-requisites: 1) 2) 3) 4)

2.3.3

Work permit is available Proper isolation has been provided Proper tools and equipment are available Consumables are available

Tools & Special Instrument: Winding machine, former, brazing tool, oven screw guage, motor checker, spanner set, screw driver set.

2.3.4

Man Power: Supervisor –1, Technician – 2

2.3.5

Expected Time of Completion: Not Applicable

2.3.6

Consumables & Spare Requirement: Copper wire, insulating paper, binding wire, RTD, Lugs, varnish, PVC sleeve, bearings.

2.3.7

Initial Observation Before Starting the Job: 1) 2)

2.3.8

Check the repairability of the fault. Efforts should be made to determine the root cause of failure of the motor. Any foreign material if recovered inside motor, the same must be immediately reported.

Safety Instruction & Precautions: 1) Prior to start of rewinding, hot spot in stator, if any, must be removed, 2) RTDs should be inserted during rewinding, 3) Winding coils must be properly tagged

2.3.9

Dismantling Procedure: As envisaged in para 1.2.1

2.3.10

Test on Equipment: As per check list No. 1) EMP/50100/01/BM/02 2) EMP/50100/01/BM/04

2.3.11

Return to Service: As per para 2.2.11

Rev. No. 0 Feb. 2002

- 15 -

- BM of HT motor - BM of LT motor

MAINTENANCE PROCEDURE 3.0

R-3&4-EMP-50100-01

TROUBLE SHOOTING: S.No.

Trouble

1.

Hot Bearing (General)

2.

Hot Bearings – Ball or Roller

Cause Excessive belt pull Pulley too far away Pulley dia too small Misalignment Bearing running dry Insufficient grease Excess lubricant Over loaded bearings

3.

Broken ball or rough races Motor connected but does No supply voltage not start One phase open Voltage too low Motor may be over loaded Control gear defective Starting torque of load is too high

4.

Motor runs and then dies down

Rotor Defective Brushes are not down due to sticking or worn brushes Short circuit to earth Fault in starters or star delta switch Power failure Over load

5.

Motor starts sluggishly speed falls when load is put on

Rev. No. 0 Feb. 2002

Not applied properly Voltage is too low at motor terminals because of line drop If wound rotor, improper operations of secondary resistance Starting load torque too high Broken rotor bars

- 16 -

Remedy Decrease belt tension Move pulley closer to bearing Use larger pulley Correct by realignment of drive Re-grease the bearing Maintain proper quantity of grease in bearings Reduce quantity of grease (Bearing should not be filled more than half) Check alignment, side thrust and end thrust Replace bearings Check voltage on each phase Reduce load or try to start uncoupled from load Examine each step of the control gear for bad contacts or open circuit. a) If of squirrel cage type and with auto transformer starting, change to higher tap, b) If it is slipring type, lower the starting resistance Look for broken rings Free brushes in holders, change worn brushes Test with Megger Check contacts and connections. Check for loose connections to line, to fuses and to control a) Examine overload trips and see that they are set correctly to approx. 150% full load current b) See that the dashpots are filled with correct quantity of oil Consult factory for proper type -- “--

--“--

Check the load characteristic with motor speed torque a) Look for crack near the ring. b) New rotor may be required as repairs are usually temporary

MAINTENANCE PROCEDURE S.No.

Trouble

Cause Open primary circuit

6.

7.

8.

Motor starts with difficulty Load too high on star connection or not at Supply voltage low all Burning of contacts in stardelta starter Stator heats up quickly and Stator wrongly connected takes a large no-load Phase – Short current Multiple earth Motor overheats while Overload running under load Motor may have one phase open Shorted stator coil Faulty connection High voltage Low voltage Rotor rubs stator bore

9.

Motor Vibrates connections are made

Foreign material in airgap Motor operated on load cycle not in accordance with the rating particulars indicated in the Name plate after Motor mis -aligned

10

Scraping Noise

11.

Magnetic noise

12.

Shaft end breaks or Stator Rotor rubbing Heavy vibrations

13.

Rev. No. 0 Feb. 2002

R-3&4-EMP-50100-01

Remedy Locate fault with testing device and repair Reduce load or use larger motor Check supply line and cables to motor Overhaul starter Check connection Rewind Short-Rewind Reduce load Check to make sure that all leads are well connected Repair and then check watt meter reading Correct the connections Check terminals of the motor with voltmeter Recondition the rotor, replace worn bearings Dismantle and remove obstruction Run the motor on duty for which it is designated

Re-align. Maintain within 0.03mm

Weak foundation

Strengthen base

Coupling out of balance Driven equipment unbalanced Defective ball or roller bearings Bearings not in line Balancing weights shifted Wound rotor coils replaced

Balance coupling Re-balance

Excessive end play

Adjust bearings or add washer. Use proper shim for alignment. Use vibration mounts dampen external vibration

Fan rubbing fan cover Fan rubbing insulation Loose on bed plate Air gap not uniform Loose bearings Excessive radial loads due to pulley drives Rotor unbalance

Remove interference Clean fan Tighten holding bolts Check and correct bracket fit or bearings Correct or renew bearings Give pulley drive details to factory and check its suitability Re-balance

- 17 -

Replace bearing Line up properly Re-balance rotor

MAINTENANCE PROCEDURE 4.0

R-3&4-EMP-50100-01

ANNEXURE.

Rev. No. 0 Feb. 2002

1)

Preventive Maintenance Check list of HT Motors – EMP/50100/01/PM/01

2)

Breakdown Maintenance Check list of HT Motors – EMP/50100/01/BM/02

3)

Preventive Maintenance Check List of LT Motors – EMP/50100/01/PM/03

4)

Breakdown Maintenance Check list of LT Motors – EMP/50100/01/BM/04

5)

Preventive Maintenance Check list of LT Motors – EMP/50100/01/BM/05

- 18 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF HT MOTORS Sheet 1 of 4 UNIT NO.

: R3/R4/R-3&4 :

CHECK LIST NO REVISION ISSUE DATE

: EMP/50100/01/PM/01 : 1 : DEC.’ 2002

EQUIPMENT TAG NO. CATEGORY

: A/B/C/D

PREPARED BY

: C.P.SHARMA, SO/E

FREQUENCY

: YEARLY/TWO YEARLY

APPROVED BY

: VIVEK JAIN SME (E)

DATE

:

RUN/SHUTDOWN CONDITION

:

CREW

: SUPERVISOR-1 TECHNICIAN-2

TOOLS

: MOTOR CHECKER, 5KV MEGGER, VACUUM CLEANER, SPANNER SET, SCREW DRIVER SET, WIRE BRUSH.

MATERIAL

: INSULATION TAPE, CLEANING AGENT, MASKING TAPE, LUBRICANT

DURATION JOB

A)

OF : 08 HOURS

PREREQUISITES: (i) (ii) (iii) (iv) (v)

Work permit is available ( No…. …………. Dt---------------) Proper isolation has been provided on CB Proper tools & equipment are available. Consumable are available. Inform RT lab and switchgear group for taking up PM of their area. -

Note :Always stand on rubber mats while working on bus bars. B)

PM CHECKS:

Sl. No. 1.0

DESIGNED / EXPECTED VALUE

DESCRIPTION GENERAL: i)

Clean motor body, fan, earthing connection with vacuum cleaner / cloth and cleaning re-gent

ii) Check foundation bolt for tightness

Tight

iii) Check healthiness of cooling fan iv) Check tightness of both the earthing connections

Rev. No. 0 Feb. 2002

Clean

- 19 -

No damage & Clean Earth at both side

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO.

Sl. No. 2.0

Sheet 2 of 4 CHECK LIST NO. : EMP/50100/01/PM/01

: R-3/R-4

DESIGNED / EXPECTED VALUE

DESCRIPTION Terminal Box (Phase side) a) Check general condition of the terminal box/chambers. b) Check tightness of lugs c) Check HT kit for any abnormality

d) Check cable lug for any overheating/ decolourisation e) Check insulator, separator etc., for cracks and correct installation f) Check gaskets of terminal box 3.0

Terminal box ( Neutral side) (if outside the motor) a) Check general condition of the terminal box b)

Check tightness of shorting links

c)

Check insulator/ separators etc. for cracks and correct installation

d)

Check gasket of terminal box

No crack, Properly installed No wear & tear Properly installed

Clean

No crack No wear & tear

Space Heater Check space heater cable glanding, connectiontightness & overheating

5.0

CB end (Tightness of Cable) a) Check lugs for over heating sign b) Check tightness of lugs

Properly glanded, all connection tight, No decolourisation No overheating Tight

c) Check any abnormality in the HT termination kit

No deformity/ damage/ overheating

CB end (Relay) Check corresponding relay(s) is/are calibrated (By RT lab)

Rev. No. 0 Feb. 2002

Tight No deformity / damage / over heating No overheating

Tight

4.0

6.0

Clean / No damage

- 20 -

Calibrated

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO.

Sheet 3 of 4 CHECK LIST NO. : EMP/50100/01/PM/01

: R-3/R-4

C) MEASUREMENT & TESTING : Note : Cross check the present measurement with the commissioning / design data and if difference of the order of 5% or more is observed, this may be informed immediately to group-in-charge In the column "DESIGNED / EXPECTED VALUE", the values obtained in the previous measurement should be filled

Sl. No. 1.

DESIGNED / EXPECTED VALUE (See note above)

DESCRIPTION

AS FOUND

AS LEFT

REMARKS

i) Measure winding resistance in M ohm. R-Y Y-B B-R ii) Space Heater (iii) Winding inductance in mH R-Y Y-B B-R iv) Insulation Resistance at 5 KV DC (*) R+Y+B to Earth a) 15 sec b) 1 Minute c) 10 Minute d) PI v) Capacitance & tan delta (By RT lab) a) Capacitance ( R+ Y+B) to Earth b) Tan delta ( R+Y+B) to Earth vi) Insulation resistance of space heater at 500V DC

D)

AREA CLEANING: Clean the work area and remove all defective consumable, spares etc.

(*) QA check point for category A equipment (PM carried out by) NAME & Designation : SIGNATURE (with Date & Time)

Rev. No. 0 Feb. 2002

- 21 -

(Checked by)

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF HT MOTORS Sheet 4 of 4 CHECK LIST NO. : EMP/50100/01/PM/01

UNIT NO.

: R-3/R-4

Feed Back Session

: To be filled by Supervisor or above. (Checking Authority) (Use extra sheets if space is not sufficient)

S. No.

Description

Observation

Remark

1.

Consumable used

Write the name & Qty.

2.

Spares used

3.

Duration of job

Write the actual duration

4.

Man power used

Write the name of man power

5.

Entry done

History file/CMMS file

6.

Setting changed

Write any setting changed

7.

Area cleaned

Switchgear area cleaned

8.

Other abnormality

Name & Signature Checking Authority

Rev. No. 0 Feb. 2002

Name & Signature Reviewing officers

- 22 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO.

:

R-3/4

CHECK LIST NO REVISION ISSUE DATE

: : :

Sheet 1 of 4 EMP/50100/01/BM/02 1 DEC.’ 2002

EQUIPMENT NO. CATEGORY

TAG : :

A / B / C/ D

PREPARED BY

:

C.P.SHARMA / S.P.GUPTA SO/E SO/E

FREQUENCY

:

NEED BASED

APPROVED BY

:

VIVEK JAIN SME (E)

DATE

:

RUN/SHUTDOWN CONDITION

:

CREW

:

SUPERVISOR-1 TECHNICIAN-2

TOOLS

:

DURATION OF JOB

:

08 HRS. TO 40 MATERIAL HRS.

A) (i) (ii) (iii) (iv) B)

PREREQUISITES: Work permit is available ( No…. …………. Dt---------------) Proper isolation has been provided on CB / MCC cell Proper tools & equipment are available. Consumable are available. BM CHECKS:

Sl. No. 1.

2.

:

MOTOR CHECKER, SPANNER SET, SCREW DRIVER SET COPPER WIRE, PAPER INSULATORS, VARNISH, SOLDERING/BRAZING EQUIPMENT, PREFABRICATED HT WINDING

DESIGNED / EXPECTED VALUE

DESCRIPTION Name plate - Details of Motor a) KW b) Voltage c) Full load current d) RPM e) Frame size f) Make g) S.No. h) Connection i) Bearing j) Class of insulation Pre & post repair inspection a) Insulation Resistance (M? ) R-E Y- E B-E R-Y Y- B B-R

Rev. No. 0 Feb. 2002

- 23 -

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO. Sl. No.

Sheet 2 of 4 CHECK LIST NO. : EMP/50100/01/BM/02

: R-3/R-4

DESIGNED / EXPECTED VALUE

DESCRIPTION b) Winding Resistance (? )

c)

R1-R2 Y1-Y2 B1-B2 R-Y R-B B-Y Winding Inductance (mH) R1-R2 Y1-Y2 B1-B2 R– Y R– B B– Y

d) RTD Resistance at ____?C RTD – 1 RTD - 2 RTD - 3 RTD - 4 RTD - 5 RTD - 6 RTD - 7 RTD - 8 e)

Space Heater Resistance (in ohm) IR Value (m? )

f)

Condition of bearings

g) General condition of motor 3.

No rusting smooth operation No rusting, No damage

Repair / Overhauling / Replacement of part/ Rewinding All dismentaled Dismantling of motor with properly tagged proper identification Tag

Rev. No. 0 Feb. 2002

- 24 -

parts

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO.

Sheet 3 of 4 CHECK LIST NO. : EMP/50100/01/BM/02 DESIGNED / EXPECTED AS AS REMARKS VALUE FOUND LEFT

: R-3/R-4

Sl. No.

DESCRIPTION a)

4.

Cleaning of stator / rotor with cleaning agent & air blower and bearing with turpentine oil and pre-post cleaning inspection Stator Rotor Temp. Sensor Space Heater Bearing Oil supply unit c) Varnishing of stator by class "F" varnish d) Rewinding i) Size of wire ii) No. of wires / slot iii) No. of slots iv) Single / Double layer v) Make & class of insulation vi) Make & class of varnish e) Baking of stator core in oven at 130 ? C f) Details of work (other than rewinding) carried out (like shaft metalising, replacement of fan, any major repair etc.) Post repair / rewinding measurement Note : Any variation of 5% or more from design values, shall be informed to group engineer a) HV test (KV for 1 min) (R+Y+B) - E b) Insulation resistance at 5KV DC (*)

c)

Rev. No. 0 Feb. 2002

i) 15 Sec ii) 1 Minute iii) 10 Minute iv) PI Capacitance & tan delta (at 1 KV AC) (*) i) Capitance (R+Y+B) to E ii) Tan delta (R+Y+B) to E

Clean Clean Clean Clean Clean Properly varnished

Completed

? ? ? ?

100 M? 100 M? 100 M? 1.8

- 25 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF HT MOTORS UNIT NO. Sl. No.

Sheet 4 of 4 CHECK LIST NO. : EMP/50100/01/BM/02

: R-3/R-4

DESIGNED / EXPECTED VALUE As per Name plate

DESCRIPTION d) No load current

AS FOUND

AS LEFT

REMARKS

R - Phase Y - Phase B - Phase e) f)

C)

Speed Operation of motor

As per Name plate Smooth without any noise & vibration

AREA CLEANING: Clean the switchgear area and remove all defective consumable, spares etc. (*) QA check point for category A equipment

(BM carried out by)

(Checked by)

NAME & Designation : SIGNATURE (with Date & Time) Feed Back Session

S. No.

: To be filled by Supervisor or above. (Checking Authority) (Use extra sheets if space is not sufficient)

Description

Observation

Remark

1. 2. 3. 4. 5.

Consumable used Spares used Duration of job Man power used Entry done

Write the name & Qty.

6. 7. 8.

Setting changed Area cleaned Other abnormality

Write any setting changed Switchgear area cleaned

Write the actual duration Write the name of man power History file/CMMS file

Name & Signature Checking Authority

Rev. No. 0 Feb. 2002

Name & Signature Reviewing officers

- 26 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF LT MOTORS Sheet 1 of 3

UNIT NO.

: R-3/R-4/R-3&4

EQUIPMENT NO. CATEGORY

TAG : :

A/B/C/D

FREQUENCY

:

YEARLY/ YEARLY

DATE

:

CREW

:

DURATION JOB A)

OF :

CHECK LIST NO.

: EMP/50100/01/PM/03

REVISION

: 2

ISSUE DATE

: DEC.’ 2002

PREPARED BY

: C.P.SHARMA, SO/E

APPROVED BY

: VIVEK JAIN, SME (E)

TWO RUN/SHUTDOWN CONDITION TOOLS

SUPERVISOR-1 TECHNICIAN-2

MATERIAL

4 HOURS-UPTO 90 KW MOTOR 8 HOURS-UPTO 200 KW MOTOR

: : MOTOR CHECKER, VACUUM CLEANER, SPANNER SET, SCREW DRIVER SET, WIRE BRUSH. : INSULATION TAPE, CLEANING AGENT, MASKING TAPE , LUBRICANT :

PREREQUISITES: i) Work permit is available ( No…. …………. Dt---------------)

ii) Proper isolation has been provided on CB / MCC cell iii) Proper tools & equipment are available. iv) Consumable are available. v) Inform CB/MCC group & protection group for taking up the PM. B) PM CHECKS: Note : Always stand on rubber mats while working on Bus bar. DESIGNED / EXPECTED VALUE

Sl. No.

DESCRIPTION

1.

VISUAL INSPECTION : Thoroughly inspect motor body, earthing connection, fan, cable, lugs, terminals etc., for any damage, corrosion, dust deposition, loose connection, over heating, blackening and tension. CLEANLINESS/TIGHTNESS CHECKS a) Clean motor body, fan, earthing connection withvacuum cleaner/cloth and cleaning re-agent

2.

No loose connection / No damage / No over heating sign

b) Check foundation bolt for tightness.

Rev. No. 0 Feb. 2002

- 27 -

Clean

Tight

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF LT MOTORS UNIT NO.

Sl. No.

Sheet 2 of 3 CHECK LIST NO. : EMP/50100/01/PM/03

: R-3/R-4

DESCRIPTION c) Check general condition of the terminal box d)

Checks power cable for glanding and inside condition. e) Check cable terminal tightness

DESIGNED / EXPECTED VALUE Properly glanded, No tension, No overheating sign. Clean, No damage

All connection tight & clean

g) Check cable lug for any overheating / decolourisation h) Check insulator, separator etc., for cracks and correct installation

No overheating Sign, No loose connection No cracks, properly installed

i)

Installed no wear & tear Sealed

j) Check extra holes for proper sealing

AS LEFT

REMARKS

All connection tight & clean

f) Check star / delta link tightness (If accessible)

Check gaskets of terminal box

AS FOUND

k) Check space heater cable for proper All connection tight glanding, connection, tightness etc. (for 30KW & above) l) Check cooling fan & cover for any No damage properly damage & correct installations. installed, clean m) Check tightness of both the earthing Earthed at both points points. n) At CB end, check connection of lugs for No over heating / No over heating sign / loose connection (for loose connection CB fed motors) o) Check that thermal overload relay is Set to _____A calibrated (for MCC fed motors) p) Check that motor protection relay is Comp leted calibrated (by RT lab) (for CB fed loads) q) Check that PM check of corresponding Completed MCC cell/ CB is completed.

C) : MEASUREMENT & TESTING Note : Cross check the present measurement with the conditioning / design data and if any difference more than 5% is observed this may be informed immediately to group-in-charge

Rev. No. 0 Feb. 2002

- 28 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST OF LT MOTORS UNIT NO.

Sl. No. 1.

Sheet 3 of 3 CHECK LIST NO. : EMP/50100/01/PM/03

: R-3/R-4

*To be filled from commissioning data / history file DESIGNED / AS DESCRIPTION EXPECTED FOUND VALUE i) Measure motor winding resistance in ohm. along with cable from source end. R-Y Y-B B-R Space heater resistance ii) Measure motor winding inductance in mH along with cable from source end. R-Y Y-B B-R iii) Measure motor winding I R at 500 V DC along with cable from source end. (**) a) (R+Y+B) to earth ? 20 ? b) Space Heater terminal to ? 20 ? earth

AS LEFT

REMARKS

D) AREA CLEANING: Clean the area and remove all defective consumable, spares etc. (**) QA check point for category ‘A’ equipment. (PM carried out by) NAME & Designation : SIGNATURE (with Date & Time) Feed Back Session: To be filled by Supervisor or above. (Checking Authority) (Use extra sheets if space is not sufficient) S. No. 1. 2. 3. 4. 5. 6. 7.

Description Consumable used Spares used Duration of job Man power used Entry done Setting changed Area cleaned

8.

Other abnormality

Observation

Remark Write the name & Qty. Write the actual duration Write the name of man power History file/CMMS file Write any setting changed Switchgear area cleaned

Name & Signature Checking Authority

Rev. No. 0 Feb. 2002

(Checked by)

Name & Signature Reviewing officers

- 29 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF LT MOTORS UNIT NO.

:

R-3 / 4

CHECK LIST NO REVISION ISSUE DATE

Sheet 1 of 4 : EMP/50100/01/BM/04 : 1 : DEC.’ 2002

EQUIPMENT NO. CATEGORY

TAG : :

A/B/C/D

PREPARED BY

: C.P.SHARMA / S.P.GUPTA SO/E SO/E

FREQUENCY

:

NEED BASED

APPROVED BY

: VIVEK JAIN SME (E)

DATE

:

:

CREW

:

SUPERVISOR-1 TECHNICIAN-2

RUN/SHUTDOWN CONDITION TOOLS

DURATION OF JOB

:

08 HRS. TO 40 HRS.

MATERIAL

: COPPER WIRE, PAPER INSULATORS, VARNISH, SOLDERING/BRAKING EQUIPMENT

A)

: MOTOR CHECKER, SPANNER SET, SCREW DRIVER SET

PREREQUISITES:

Work permit is available ( No…. …………. Dt---------------) i) Proper isolation has been provided on CB / MCC cell ii) Proper tools & equipment are available. iii) Consumable are available.

B)

BM CHECKS:

Sl. No.

DESIGNED / EXPECTED VALUE

DESCRIPTION

1.

Name plate - Details of Motor k) KW l) Voltage m) Full load current n) RPM o) Frame size p) Make q) S.No. r) Connection s) Bearing j) Class of insulation 2. Pre & post repair inspection (*) Insulation Resistance (M? ) R-E Y- E B-E R-Y Y– B B-R (*) QA check point (post repairs) applicable for category A equipment

Rev. No. 0 Feb. 2002

- 30 -

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF LT MOTORS UNIT NO. Sl. No. 2.

Sheet 2 of 4 CHECK LIST NO. : EMP/50100/01/BM/04

: R-3/R-4

DESIGNED / EXPECTED VALUE

DESCRIPTION iv) Winding Resistance ( ? ) R1 - R2 Y1 - Y2 B1 - B2 R-Y R-B B-Y v) Winding Inductance ( mH ) R1 - R2 Y1 - Y2 B1 - B2 R-Y R-B B-Y vi) RTD Resistance at _______ ? C RTD – 1 RTD – 2 RTD – 3 RTD – 4 RTD – 5 RTD – 6 RTD – 7 RTD – 8 vii) Space Heater Resistance (? ) IR Value (M? )

3.

viii)Condition of bearings xi) General condition of motor Repair / Overhauling / Replacement of part/ Rewinding a) Dismantling of motor with proper All dismantled identificationTag parts properly tagged b) Cleaning of stator / rotor with cleaning agent & air blower and bearing with turpentine oil and pre-post cleaning inspection Stator Clean Rotor Clean Temp. Sensor Clean Space Heater Clean Bearing Clean Oil supply unit Clean

Rev. No. 0 Feb. 2002

- 31 -

AS FOUND

AS LEFT

REMARKS

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF LT MOTORS Sheet 3 of 4 UNIT NO. Sl. No.

: R-3/R-4

CHECK LIST NO. : EMP/50100/01/BM/04

DESCRIPTION c) Varnishing of stator by class "F" varnish

DESIGNED / EXPECTED VALUE Properly varnished

AS FOUND

AS LEFT

REMARKS

d) Rewinding i) Size of wire ii) No. of wires / slot iii) No. of slots iv) Single / Double layer v) Make & class of insulation vi) Make & class of varnish e) Baking of stator core in oven at 130 ? C

Completed

f) Details of work (other than rewinding) carried out (like shaft metalising, replacement of fan, any major repair etc.) 4.

Post repair / rewinding measurement With stand Note: Any variation of 5% or more from design successfully value shall be informed to group engineer. g) HV test (1KV for 1 min) * (R+Y+B) to E b) No load current As per name plate details R – phase Y – phase B – phase c) Speed As per name plate details d) Operation of motor Smooth without noise & vibration * - QA check point for category A equipment. C)

AREA CLEANING: Clean the area and remove all defective consumable, spares etc.

(BM carried out by) NAME & Designation : SIGNATURE (with Date & Time)

Rev. No. 0 Feb. 2002

- 32 -

(Checked by)

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT BREAK DOWN MAINTENANCE CHECK LIST OF LT MOTORS Sheet 4 of 4 CHECK LIST NO. : EMP/50100/01/BM/04

UNIT NO.

: R-3/R-4

Feed Back Session

: To be filled by Supervisor or above. (Checking Authority) (Use extra sheets if space is not sufficient)

S. No.

Description

Observation

Remark

1.

Consumable used

Write the name & Qty.

2.

Spares used

3.

Duration of job

Write the actual duration

4.

Man power used

Write the name of man power

5.

Entry done

History file/CMMS file

6.

Setting changed

Write any setting changed

7.

Area cleaned

Switchgear area cleaned

8.

Other abnormality

Name & Signature Checking Authority

Rev. No. 0 Feb. 2002

Name & Signature Reviewing officers

- 33 -

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST FOR VENTILATION FAN Sheet 1 of 2 UNIT NO.

:

CHECK LIST NO.

: EMP/50100/01/PM/05

:

REVISION

: 0

FEEDER NO.

:

ISSUE

:

CATEGORY

:

FREQUENCY

EQUIPMENT NO.

TAG

R-3/4

PREPARED BY

: S.KANDPAL/PRATEEK AGRAWAL SO/B SO/E

:

APPROVED BY

: VIVEK JAIN SME (E)

DATE

:

RUN/SHUTDOWN CONDITION

:

CREW

:

SUPERVISOR - 1 TECHNICIAN - 2

TOOLS/EQUIP

: SPANNER SET, ALLEN KEY SET, SCREW DRIVER, MALLET, PULLER

:

2 HOUR

MATERIAL

: MARKENE CLOTH, LUBRICATION GREASE

DURATION JOB

A)

OF

A/B/C/D

DATE

PRE-REQUISITE:

1)

Work permit is available.

(No. __________ Dt. _______________)

2)

Drawings are available.

: __________________________________

3)

Proper tools and instruments are available.

: __________________________________

4)

Consumables are available.

: __________________________________

5)

Before starting the job ensure isolation is been given.

:___________________________________

S.No

Description

1 2

Cleanliness of ventilation fan Check for corrosion

3

Tightness of fan blade on hub

Rev. No. 0 Feb. 2002

Expected value Clean No corrosion on the blade Blade tight on the hub

- 34 -

As found

As left

Remarks

MAINTENANCE PROCEDURE

R-3&4-EMP-50100-01

RAJASTHAN ATOMIC POWER STATION-3&4 ELECTRICAL MAINTENANCE UNIT PREVENTIVE MAINTENANCE CHECK LIST FOR VENTILATION FAN Sheet 2 of 2 UNIT NO. EMP/50100/01/PM/05 S.No

: R-3/R-4

CHECK LIST NO.

Description

Expected value

4

Tightness of hub and fan blade assembly on shaft

Fan blade assembly is tight

5

Check for axial and radial play

No play axially (ensured by key in key way) No play radially (ensured by circlip or tightening screw)

6

When mounting in duct check fan blade for clearance with duct.

Clearance ensured for free rotation of blade

As found

(PM carried out by) SIGNATURE (Date & Time)

:

As left

Remarks

(Checked by)

:

Name & Desgn. :

Feed Back Session

S. No. 1. 2. 3. 4. 5. 6. 7.

: To be filled by Supervisor or above. (Checking Authority) (Use extra sheets if space is not sufficient)

Description

Observation

Remark

Consumable used Spares used Duration of job Man power used

Write the name & Qty.

Write the actual duration Write the name of man power History file/CMMS file Area should be cleaned

Entry done in Area cleaned Other abnormality

Signature

:

Signature

:

Name Checking Authority

:

Name Reviewing officer

:

Rev. No. 0 Feb. 2002

- 35 -