Hkkjr ljdkj GOVERNMENT OF INDIA MINISTRY OF RAILWAYS

Hkkjr ljdkj GOVERNMENT OF INDIA

jsy ea=ky; MINISTRY OF RAILWAYS

egkjktiqj, Xokfy;j & 474 005

Maharajpur, GWALIOR - 474 005

CAMTECH/ E/14-15/PSI-Sch/1.0

July, 2014

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(For Official Use Only)

REVIEW OF

MAINTENANCE SCHEDULE FOR PSI TARGET GROUP: PSI MAINTENANCE STAFF (TRD)

REVIEW

OF MAINTENANCE SCHEDULE FOR PSI

QUALITY POLICY

“To develop safe, modern and cost

effective Railway Technology complying

with Statutory and Regulatory

requirements, through excellence in

Research, Designs and Standards and

Continual improvements in Quality

Management System to cater to

growing demand of passenger and

freight traffic on the railways”.

FOREWORD

Power Supply Installation (PSI) provides energy to electrically driven locomotives &

EMUs. For utmost utilization of traction assets, outage of PSI equipment should be

minimum. For this proper maintenance of PSI is essential to cater growing demand of

passenger and freight traffic on the Railways.

CAMTECH has prepared this handbook on “Review of Maintenance Schedule for PSI”

to achieve the above objective. This handbook contains details of various maintenance

schedules, schedule action plan and formats for submitting failures to RDSO used for these

schedules.

I hope this handbook will prove to be useful for the maintenance personnel working in

TrD/PSI (Power Supply Installation).

CAMTECH, Gwalior A.R.Tupe

Date: 23rd July 2014 Executive Director

PREFACE

Power Supply Installation (PSI) provides power to Over Head Equipment (OHE) to

cater power to electric locomotives & EMUs. PSI comprises lot of electrical equipment in

Traction Sub Stations (TSS), Sub Sectioning Post (SSP), and Sectioning Post (SP) with their

associated fittings, insulators and other attachments. For utmost utilization of traction assets,

outage of overhead equipment should be minimum and for this proper schedule maintenance

of PSI assets is essential.

This handbook on Review of Maintenance Schedule for PSI has been prepared by

CAMTECH with the objective of making PSI maintenance personnel aware of correct

maintenance procedure, schedule action plan and formats for submitting failures to RDSO

upkeep of records and repair techniques.

It is clarified that this handbook does not supersede any existing provisions laid down

by Railway Board, RDSO or AC Traction Manual (ACTM). This hand book is for guidance

only and it is not a statutory document.

I am sincerely thankful to TI Directorate, RDSO/Lucknow and also all field

personnel who helped us in preparing this handbook.

Technological up-gradation & learning is a continuous process. Please feel free to

write to us for any addition/ modification in this handbook. We shall highly appreciate your

contribution in this direction.

CAMTECH, Gwalior ( Peeyoosh Gupta) Date: 22nd July 2014 Director (Electrical) e - mail id : [email protected]

CONTENTS

Item Description Page No.

Foreword iii

Preface iv

Content v

Correction Slip ix

1.0 INTRODUCTION 1

2.0 OBJECTIVE OF MAINTENANCE 1

3.0 MAINTENANCE SCHEDULES 1

3.1 FORTNIGHTLY SCHEDULE 2

3.1.1 Battery & Battery Charger 2

3.2 MONTHLY SCHEDULE 3

3.2.1 General Works on TSS, SSP & SP 3

3.2.2 Power Transformer 4

3.2.3 Safety Precautions before Maintenance of Circuit Breaker/ Interrupter 5

3.2.4 25 kV Vacuum Circuit Breaker / Interrupter 5

3.2.5 132 kV SF-6 Circuit Breaker (120 SFM -32B) 7

3.2.6 25 kV SF-6 Circuit Breaker (50 SFGP-20A) 8

3.2.7 132/25 kV SF-6 Circuit Breaker (70 SFM- 32A

& 120 SFM -32A) 9

3.2.8 220 kV SF- 6 Circuit Breaker (ELF SL- 4-1) 12

3.2.9 25 kV SF-6, Circuit breaker/ Interrupter (EDF SK-1-1(S)

& EDF SK -1-1) 13

3.2.10 25 kV SF-6, Interrupter (30 SFGP-25A

& 25 SFGP-25A) 14

3.2.11 25 kV Minimum Oil Interrupter (HPGE 7/9A) 16

3.2.12 25 kV SF-6 Circuit Breaker (LTB 72.5 D1) 17

3.2.13 Auxiliary Transformer 18

3.2.14 220/132/25 kV Current Transformer 19

3.2.15 220/132 kV Isolator, Double pole & Triple pole 20

3.2.16 25 kV Isolator, Single pole, Double pole & Bipolar 20

3.2.17 198/120/42 kV Surge Arrester 21

3.2.18 Series Reactor (Oil Type) 21

3.2.19 Series Reactor (Dry Type) 22

3.2.20 Control and Relay Panel 23


3.2.21 Battery Charger 23

3.2.22 25 kV Motorised Isolator, Single pole 24

3.3 QUARTERLY SCHEDULE 25



3.3.3 25 kV Potential Transformer 25

3.3.4 25 kV Motorised Isolator 26


3.3.6 Capacitor Bank 27


3.3.8 AC/ DC Distribution Panel 28

3.4 HALF YEARLY SCHEDULE 29



3.4.3 25 kV Vacuum Circuit Breaker / Interrupter 30

3.4.4 132 kV SF-6 Circuit Breaker (120 SFM -32B) 31

3.4.5 25 kV SF-6 Circuit Breaker (50 SFGP-20A) 32


& 120 SFM -32A) 33

3.4.7 220 kV SF- 6 Circuit Breaker (ELF SL- 4-1) 34


& EDF SK -1-1) 35

3.4.9 25 kV SF-6, Interrupter (30 SFGP-25A & 25 SFGP-25A) 36

3.4.10 25 kV Minimum Oil Interrupter (HPGE 7/9A) 37

3.4.11 25 kV SF-6 Circuit Breaker (LTB 72.5 D1) 38




3.4.15 220/132 kV Isolator 40

3.4.16 25 kV Isolator 40



3.4.19 25 kV Capacitor Bank 42



3.4.22 Condition Based Maintenance through Thermo vision Camera (Traction Substation) 28th MSG TRD at

SCR on Feb 2011 item no. 28.19 43

3.4.23 Earthing & Bonding 44



3.4.25 AC/DC Distribution Panel 45

3.5 YEARLY SCHEDULE 45



3.5.3 25 kV Vacuum Circuit Breaker/ Interrupter 47

3.5.4 132 kV SF- 6 Circuit Breaker (120 SFM -32B) 48

3.5.5 25 kV SF- 6 Circuit Breaker (50 SFGP-20A) 49


& 120 SFM -32A) 50

3.5.7 220 kV SF-6 Circuit Breaker (ELF SL- 4-1) 51


& EDF SK -1-1) 52

3.5.9 25 kV SF-6, Interrupter (30 SFGP-25A & 25 SFGP-25A) 53

3.5.10 25 kV Minimum Oil Interrupter (HPGE 7/9A) ` 54

3.5. 11 25 kV SF-6 Circuit Breaker (LTB 72.5 D1) 55



3.5.14 220 kV/132 kV/25kV Current Transformer 57

3.5.15 220/132/ kV Isolator 57

3.5.16 25 kV Isolator 58



3.5.19 Capacitor Bank 59


3.5.21 Series Reactor (Dry Type) 60


3.5.23 Condition Based Maintenance through Thermo- vision Camera (Traction Substation) 61

3.5.24 Earthing & Bonding 61


3.5.26 AC/DC Distribution Panel 62

3.6 THREE YEARLY SCHEDULE 62

3.6.1 SF-6 Circuit Breaker & Interrupter 62


3.7 AFTER 5 YEARS OR WHEN NEEDED 63


3.7.2 Vacuum circuit Breaker & Interrupter 64

3.8 SIX YEARLY SCHEDULE 64

3.8.1 SF-6 Circuit Breaker & Interrupter 64


3.9 PERIODIC OVERHAULING 65



3.9.3 Vacuum circuit Breaker & Interrupter 73


3.10 PRE MANSOON AND PRE WINTER PRECAUTIONS 74

4.0 SCHEDULE ACTION PLAN 75

5.0 FORMATS FOR SUBMITTING FAILURES TO RDSO 77

TIF-0011 Rev. 0 PART-I - Protective Relay Data 77

TIF-0011 Rev. 0 PART-II - Tripping Data Relay Wise 77 TIF-0011 Rev. 0 PART-III - Tripping Data 78

TIF-0014 Rev. 0 PART-II - Make wise Breakup of Traction Transformers 78

TIF-0014 Rev.0 PART-III - Details of Testing Kit Available for Transformer Testing 79

TIF-0014 Rev.0 PART-IV - Failure Reporting of The Transformer 79

TIF-0015 Rev.0 PART-I - Performance of Capacitor Banks 80

TIF-0015 Rev.0 PART-II - Performance Monitoring of Series Reactor 80

TIF-0015 Rev. 0 PART-III - Details of Testing Kit Available for Testing 81

TIF 0015 Rev. 0 PART-IV - Failure Reporting of Shunt Capacitor Bank 81

TIF-0015 Rev. 0 PART-V - Details of the Protection Provided for Shunt Capacitor 82

TIF-0016 Rev. 0 PART- II - Year Wise and Make Wise Breakup of Circuit Breaker 82

TIF-0016 Rev. 0 PART III - Statistics of AC Circuit Breaker 83

TIF-0016 Rev. 0 PART V - Year Wise And Make Wise Breakup of Interrupter 83

TIF-0016 Rev.0 PART VI - Statistics of AC Interrupter 84

TIF-0017 Rev. 0 PART -I - Failure Format for SCADA 84

TIF-0017 Rev. 0 PART -II - Statement Showing Make Wise SCADA 85 TIF 0023 Rev.0 PART II - Information on Auxiliary Transformer System 85

TIF-0024 Rev 0, PART -I - Measurement of Resistive Leakage Current of Surge Arrestor. RDSO TI/MI/0041 Rev.1 86

ANNEXURE - I 87

ANNEXURE - II 88

ANNEXURE - III 89

ANNEXURE - IV 89

ANNEXURE - V 90

ANNEXURE - VI 91

ANNEXURE - VII 91

ANNEXURE - VIII 92

ANNEXURE – IX 93

REFERENCES 97

ISSUE OF CORRECTION SLIPS

The correction slips to be issued in future for this handbook will be numbered as

follows :

CAMTECH/E/14-15/PSI-Sch/C.S. # XX date---------

Where “XX” is the serial number of the concerned correction slip (starting from 01

onwards).

CORRECTION SLIPS ISSUED

Sr. No. Date of issue Page no. and Item no.

modified

Remarks

CAMTECH/E/14-15/Sch-PSI/1.0

Review of Maintenance Schedule for PSI July, 2014

1

1.0 INTRODUCTION

Since the electric traction system depends upon continuous availability of power

supply, sub-stations and switching stations have to be kept in proper working condition at all

the time. To ensure this, the 25 kV feeder lines and traction transformers with associated

switchgear and control and relay panels are duplicated so that if one unit fails, the standby

unit can be brought into service to continue power supply. All switching operations are also

centralized and controlled by remote operation by a single authority namely Traction

Power Controller.

To achieve high reliability and zero defects on PSI assets, it is necessary to maintain

the PSI assets in perfect condition through proper schedule maintenance/checks on its

geometry and all parameters adopted in the design without compromising on safety of the

equipment as well as personnel.

No work of any kind shall be commenced on or in the vicinity of live equipment

unless power supply to the particular part has been switched off and all other prescribed

safety measures taken.

The maintenance schedule shall normally be adopted for trouble free service.

However these shall be reviewed periodically based on experience gained.

2.0 OBJECTIVE OF MAINTENANCE

The main objective of maintenance is to ensure trouble free operation of switchgear

by timely and adequate attention so that failure could be avoided through preventive and

periodical maintenance. This results in low down time and more availability of the

equipment.

Periodic review of the effectiveness of maintenance schedules shall be done.

3.0 MAINTENANCE SCHEDULES

Before starting maintenance of any switchgears, ensure that the instruction manual of

the equipment issued by the manufacturer have been fully studied and full knowledge of the

working of switchgears is available with the maintenance personnel. Otherwise there may be

adverse effect on the performance of switchgears and it may also endanger the safety of

working personnel.

The following maintenance schedules of Power Supply Installation assets are being

followed in Indian Railways:

1. Fortnightly Schedule

2. Monthly Schedule

3. Quarterly Schedule

4. Half yearly Schedule

5. Yearly Schedule

6. Three yearly schedule

7. Five yearly schedule

8. Six Yearly schedule

9. Periodic Overhaul (POH)

10. Pre- monsoon and Pre -winter precaution


July, 2014 Review of Maintenance Schedule for PSI

2

3.1 FORTNIGHTLY SCHEDULE

3.1.1 Battery & Battery Charger

Sl.

No

Item Inspection And Work To Be Carried Out Remark

1. Specific

gravity

Check and record the specific gravity of

each cell.

1210 at 27°C

& discharge at

1150

2. Distilled water Check the level of electrolyte of the cells.

Top up, if necessary.

Up to maximum

mark

3. Temperature Check & record the temperature of each

cell.

Record

4. Sulphation Check & clean sulphation on terminal

connectors and apply petroleum jelly.

Clean

5. Condition of

plate

Check & clean physical condition such as

cracks, distortions and accumulation of

whitish deposit.

Clean and

replace defective

plate

6. Cell voltage Check & record the voltage of each the

cells.

2.0V to 2.2 V

7. Total voltage Check & record the total voltage of the

battery.

Not less than

110.0 V

8. Vent plugs Check the clear passage of gases. If hole

blocked, clean it.

Clean the hole

9. Sedimentation

and any internal

damage

Check the cells for undue sedimentation and

any internal damage. If observe clean it.

Without

sedimentation &

damage

10. Inter cell

connections

Check & clean with dry cloth. Replace

defective nuts, bolts & washers.

Tighten

a. AC and DC

panel Voltage

Check AC and DC voltage on panel and

record AC and DC voltage.

Record

11. Battery charger

Check smooth operation of all switches of

battery charger. Note charging rate and AC

& DC voltage in register.

Smooth

operation

12. Battery room Clean the room. Clean



3

3.2 MONTHLY SCHEDULE

3.2.1 General Works on TSS, SSP & SP

Sl.

No


1. General

cleanliness

Check surface of the roadway, proper

drainage, rail access and pathways in the

substation. Roadway and pathway should be

firm and sufficiently elevated to prevent

water-logging and proper drainage.

Condition

fulfill

2. Vegetation Check & clean vegetation near around

equipment and yard.

Free from

vegetation

3. Tree and

branches

Check & trim tree branches likely to come in

the vicinity of live lines.

Cut or trim

4. Stored lubricating

or transformer oil

Check for security and fire risk. Keep oil

safe place and no combustible material is in

the vicinity of oil.

Secure

5. Caution, danger

board, shock

treatment chart

and other boards

Check & clean for damages, availability

and well secured, replace if damage.

Replace

6. Fire

extinguishers, fire

buckets and first

aid box

Check for expiry, fill up fine sand and

complete with necessary medicines.

Intact and

serviceable

7. Structure and

plant foundations

Check for any sinking or cracking and go

round the structural work for checking

tightness of various bolts and nuts.

No damages

8. All indication

lamps on control

panels

Check loose connections, fuse indication

etc. Tighten the same and replace the fuse

indication if required.

Tight &

replace

9. State electricity

board readings

Check & record meter reading, MD,

variation in voltage, frequency and power

factor and important data parameters.

Record

10. All jumpers &

other connections

Check visually for flash/ spark marks on

jumper, nuts & bolts. Tighten the respective

bi-metallic clamp/ connections. Replace if

required.

Check & tight

11. Discharge rod Check for cable strands broken and

damages. If strands 20% broken replace the

cable.

Replace



4

3.2.2 Power Transformer RDSO (TI/MI/00038 REV.1)

Sl.

No

Item Inspection And Work To Be

Carried Out

Remark

1. Maximum

temperature of

transformer oil on

dial indicator

Check and compare it with the

previous values. Abnormal change in

the temperature should be further

investigated and reset indicator.

Record and reset

2. Maximum

temperature of

transformer winding

on dial indicator

Check and compare it with the

previous values. Abnormal change in

the temperature should be further

investigated and reset indicator.

Record and reset

3. Oil level in

conservator (MOLG)

Check as per transformer oil

temperature indicator (OTI). If low,

top up with the filtered oil.

Top up if required

4. Buchholz Relay Check for gas collection. In case gas is

collected the same should be sent for

DGA.

As per RDSO

guide line for

DGA refer Annex.

2.04 of ACTM Vol

II, Part I.

5. Oil level in OIP

condenser bushing

Check for oil level with reference to the

oil level indicator :

In case of sealed bushing, if no

oil/less than minimum level

indication. Measure Tan- Delta &

capacitance and compare the test

values recorded earlier.

In case of oil filled bushing if any

leakage is observed, the same shall

be attended.

Max. allowable

Tan Delta - 0.007

and Capacitance

is 110% of the

factory set value

respectively

6. Tap changer Check & record the position of

standby and service transformer.

Record

7. Tank, Radiators,

Conservator, Bushing,

Oil level indicator,

gauges

Check & clean dirt deposits, leakage

and crack. If crack/leakage is

observed, replace /attend it.

Attend



5

Sl.No Item Inspection And Work To Be Carried Out Remark

8. Dehydrating

breather

Check breather for choking due to insect

build /dirt. If breather is choked, remove

the dirt etc.

Check the intactness of gasket and color of

the silica gel. If gasket is damage and silica

gel is pink, replace the same, with new

gasket and dry silica gel or recondition the

old silica gel. If the silica gel is too wet

check the BDV of transformer oil.

Check oil level in the oil cup. Fill up oil in

cup if required.

If BDV is less

than 50 kV,

filter the oil till

it reaches 50 kV

9. Heater in

marshalling box

Check for proper functioning. In case not

working, the connection should be checked

and rectified.

Working

condition

10. Sound Check abnormal humming, observe arrest the

humming sound.

Find out the

reason

11. All external

connection

Check visually that all connections are normal

without any discoloration due to local heating.

In case of any sign of heating, clean and

tighten the bolts and nuts.

Take corrective

action

3.2.3 Safety Precautions before Maintenance of Circuit Breaker/ Interrupter

Switch off all the auxiliary supplies of the equipment.

Circuit/ Interrupter are in the open condition.

Circuit/ Interrupter and sequential isolators are fully open condition.

Discharge the spring.

3.2.4 25 kV Vacuum Circuit Breaker / Interrupter

Make - ALIND, Type –VSE/5/20

Make - BHEL, Type – PVTB/PVTI

Make - ABB, Type – FSK-II

Sl.

No.


1. Surface of porcelain

pole insulator unit

Check for damages, flash mark, chipping

insulators. Replace if required. Clean with

dry cotton cloth for dirtiness.

Replace &

clean

2. Magnetic actuator

operating

mechanism and

drive link

assembly, if

applicable

Check presence of dust, looseness of bolts

and distortion in the operating mechanism.

Clean the same with dry cloth tighten the

bolts and investigate the problem in

mechanism & rectify.

Check &

rectify



6

Sl.

No.


3. Counter reading

Check operation of counter and record

counter reading of CB/BM:

- Before maintenance

- After maintenance

Function

properly

4. Mechanism box Open the cover check & clean mechanism

box for condensation rain water, gasket of

door, dust and hinges. Arrest the reason

and attend it.

Clean & apply

weather

sealant

material as per

annexure ‘V’

5. Heater, thermostat

& lamp

Check function of heater, thermostat &

lamp. If any defect attend it.

Function

properly

6. Position of

indicator

Check alignment and missing indicator.

In position

7. Control circuit

Check & record operating voltage, control

circuit wiring and connection should have

proper lugs and ferule number in terminal

box.

Record

voltage and

proper lug &

ferule

8. Tripping

mechanism

Check & correct operation of tripping

mechanism.

Function

properly

9. Shaft of the pole

assembly

Check visibility of red band on the

shaft of the pole assembly.

Visible

10. Auxiliary circuits Check the connections & function of

auxiliary control circuit and supply voltage

is correct.

Connections

are according

to the diagram

11. Local/Remote

switch operation

Check the operation of breaker on local

and remote switch. Breaker should have

open & close on selected position.

Function

properly

12. Connections

Check loose/overheating connections.

Tight if found loose.

Tighten

13. Earth connections &

foundation bolts

Check & tight the earth connections &

foundation bolts.

Tighten

14. Condenser tripping

device for CB

Check the function of CTD proper

operation. If defective, attend the same.

Function

properly

15. Anti pumping

device for BM

Check the function of APD for proper


Function

properly

16. Interlocking Check the function of interlock with

isolator.

Function

properly



7

3.2.5 132 kV SF-6 Circuit Breaker

Type - 120 SFM - 32B, Make - CGL

Sl.

No.

Item Inspection And Work To Be Carried

Out

Remark

1. Surface of

porcelain pole

insulator unit




Replace & clean

2. Counter

reading


counter reading of CB:

- Before maintenance

- After maintenance

Function

properly

3. Gas pressure Check & record gas pressure with

temperature.

7.0 kg/cm sq at

20 deg temp.

4. Mechanism

box

Open the cover check & clean mechanism



and attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’

5. Heater,

thermostat &

lamp



Working &

setting of

thermostat is 25

– 30 deg. C

6. Control

circuit




box.

Record voltage

and proper size

lug & ferule

7. Local/Remote

switch

operation




Function

properly

8. Local and

remote switch

Check the function of local and remote

switch.

Function

properly

9. Position of

indicator


In position

10. Shock

observer

Check the oil leakage from shock absorber.

Repair or replace, if necessary.

Repair or replace

11. Limit switch

& auxiliary

contact

Check & clean the function of auxiliary

limit switch, switches, contact and

connection for tightness.

Function properly

& tighten

connection



8

Sl. No. Item Inspection And Work To Be Carried Out Remark

12. Condenser

tripping device,

if provided.

Check the function of CTD proper operation.

If defective, attend the same.

Function

properly

13. Anti pumping

device



Function

properly

14. Interlocking Check the function of interlock with isolator. Function

properly

3.2.6 25 kV SF-6 Circuit Breaker (GCB)

Type- 50 SFGP - 20A, Make CGL

Sl.No. Item Inspection And Work To Be Carried Out Remark

1. Surface of

porcelain pole

insulator unit




Replace &

clean

2. Counter

reading



Before maintenance

After maintenance

Function

properly

3. Gas pressure Check & record gas pressure and temperature. 5.0 kg/cm sq at

20 deg temp.

4. Space heater,

thermostat &

lamp

Check function of heater, thermostat & lamp.

If any defect attend it.

Working &

setting of

thermostat is 25

– 30 deg. C

5. Mechanism

box

Open the cover check & clean mechanism


door, dust and hinges. Arrest the reason and

attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’

6. Main terminal Check the main terminal for discoloration,

overheated & rusted nuts, bolts & washer.

Replaced, if required.

Replace

7. Shock

absorber

Check the oil leakage from shock absorber.

Repair or replace, if necessary.

Repair or

replace

8. Control circuit




box.

Record voltage

and proper size

lug & ferule



9

Sl.No. Item Inspection And Work To Be Carried

Out

Remark

9. Local/Remote

switch

operation




Function properly

10. Local and

remote switch


switch.

Function properly

11. Position of

indicator


In position

12. Limit switch

& auxiliary

contact


limit switch, switches, contact and

connection for tightness.

Function properly

& tighten

connection

13. Earth

connections &

foundation


foundation bolts. If found loose.

Tighten

14. Condenser

tripping device



Function properly

15. Anti pumping

device


operation. If defective, attend the same

Function properly


isolator.

Function properly

3.2.7 132/25 kV SF- 6 Circuit Breaker

Type- 70- SFM- 32A, MAKE - CGL

Type- 120- SFM -32A, MAKE - CGL

Sl.

No.


Carried Out

Remark

1. Surface of

porcelain pole

insulator unit

Check for damages, flash mark,

chipping insulators. Replace if

required. Clean with dry cotton

cloth for dirtiness.

Replace & clean

2. Counter reading

Check operation of counter and

record counter reading of CB:

Before maintenance

After maintenance

Function properly



10

Sl.

No.

Item Inspection And Work To

Be Carried Out

Remark

3. Gas pressure Check & record gas pressure and temperature.

70 – SFM – 32A Gas pressure 5.0 kg/cm sq. at

20 deg C

120 – SFM – 32A Gas pressure 6.0 kg/cm sq. at

20 deg C

4. Air pressure Check & record air pressure with temperature as per OEM.

70 – SFM – 32A

Low air pressure alarm ON

13.2 ±0.3 kg/cm sq.

Low air pressure alarm OFF

14.2 ±0.3 kg/cm sq.

Low air pressure cutout switch

ON 12.00 ±0.3 kg/cm sq.

Low air pressure cutout switch

OFF

13.00 ± 0.3 kg/cm sq.

120 – SFM – 32A

Low air pressure alarm ON

13.5 ±0.3 kg/cm sq.

Low air pressure alarm OFF

14.5 ±0.3 kg/cm sq.

Low air pressure cutout

switch ON 13.00 ±0.3

kg/cm sq.

Low air pressure cutout

switch OFF

14.00 ±0.3 kg/cm sq.

5. Air leakage Check pneumatic system

such as valves, piping for

air leak sound.

No leakage

6. Compressor

setting

Check & record auto start / cut off compressor setting.

70 – SFM – 32A

Governor Switch ON-14.5

±0.3 kg/cm sq.

- Governor Switch OFF-15.5

±0.3 kg/cm sq.

120 – SFM – 32A

Governor Switch ON-14.8

±0.3 kg/cm sq.

- Governor Switch OFF-15.8

±0.3 kg/cm sq. as per manual

7. Compressor oil Check compressor oil. Top

up, if required.

Top up specified oil

8. Air reservoir

draining

Check & drain water from

air reservoir tank.

Drain water as & when

required



11

Sl.

No.


Out

Remark

9. Space heater,

thermostat &

lamp



Working &

setting of

thermostat is 25 –

30 deg. C

10. Mechanism box Open the cover check & clean

mechanism box for condensation rain

water, gasket of door, dust and hinges.

Arrest the reason and attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’

11. Main terminal Check the main terminal for

discoloration, overheated & rusted nuts,

bolts & washer. Replaced, if required.

Replaced

12. Control circuit

Check & record operating voltage,

control circuit wiring and connection

should have proper lugs and ferule

number in terminal box.

Record voltage

and proper size

lug & ferule

13. Local/Remote

switch operation


and remote switch. Breaker should

have open & close on selected position.

Function properly

14. Local and remote

switches


switch.

Function properly

15. Condenser

tripping device



Function properly

16. Anti pumping

device



Function properly

17. Position of

indicator

Check alignment and missing indicator. In position

18. Auxiliary switch /

switch contact

and terminal

block.


limit switch, switches, contact,

connection and terminal block for

tightness.

Function properly

& tighten

connection


isolator.

Function properly

20. Earth connections

& foundation


foundation bolts.

Tighten



12

3.2.8 220 kV SF- 6 Circuit Breaker

Type -ELF SL- 4-1 Double Pole/ Triple pole,

MAKE – ABB

Sl.

No.


Out

Remark

1. Surface of

porcelain pole

insulator unit




Replace & clean

2. Counter reading Check operation of counter and record


Before maintenance

After maintenance

Functioning

3. Gas pressure Check & record gas pressure and

temperature.

Gas pressure 7.0

bar at 20° temp.

4. Air pressure Check & record air pressure with

temperature as per OEM Low air pressure

alarm ON 18.0 bar.

Pressure switch for

closing blocking 17.3

bar.

Pressure switch for

auto trip 17.0 bar.

Pressure switch for

tripping blocking

16.7 bar.

5. Air leakage Check pneumatic system such as valves,

piping for air leak sound.

No leakage

6. Compressor oil Check compressor oil. Top up, if required. Servo-150

7. Air reservoir

drainage

Check & drain water from air reservoir

tank.

Drain water as &

when required

8. Compressor

motor & ‘V’

belt

Check carbon brushes and clean

commutator with cotton cloth. Check

tension of belt.

Tension < 2 times

of belt diameter.

9. Space heater,

thermostat &

lamp



Function properly




and attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’



13

Sl.

No.


Out

Remark

11. Control circuit




box.

Record voltage

and proper size

lug & ferule

12. Local/Remote

switch

operation




Function properly

13. Local and

remote switches


switch.

Function properly

14. Condenser

tripping device



Function properly

15. Anti pumping

device



Function properly


isolator.

Function properly

17. Earth

connections &

foundation



Tighten

3.2.9 25 kV SF- 6, Double Pole, Circuit Breaker/Interrupter

Type- EDF SK-1-1(S), MAKE - ABB

Type- EDF SK-1-1, MAKE - ABB

Sl.

No.


1. Surface of

porcelain pole

insulator unit




Replace & clean

2. Counter

reading


counter reading of CB/BM:

Before maintenance

After maintenance

Function

properly


temperature.

Gas pressure 7.0

bar at 20° temp.

4. Heater,

thermostat &

lamp



Working &

setting of

thermostat is 25

– 30 deg. C



14

Sl.

No.


Out

Remark

5. Main terminal Check the main terminal for

discoloration, overheated & rusted nuts,

bolts & washer. Replace, if required.

Replace

6. Shock observer Check the oil leakage from shock

absorber.

Repair or replaced, if necessary.

Replace

7. Control circuit




box.

Record voltage

and proper size

lug & ferule

8. Local/Remote

switch

operation




Function properly

9. Local and

remote switches


switch.

Function properly

10. Position of

indicator


11. Limit switch &

auxiliary contact


limit switch, switches, contact, connection

and terminal block for tightness.

Function properly

& tighten

connection

12. Density Monitor Check loose connection of cable and gas

leakage from non return valve.

Secured and no

leakage

13. Condenser

tripping device

for CB



Function properly

14. Anti pumping

device



Function properly


isolator.

Function properly

16. Earth

connections &

foundation

Check & tighten the earth connections &


Tighten

3.2.10 25 kV SF- 6, Interrupter ( Single & Double Pole)

Type- 30 SFGP – 25 A, MAKE – CGL

Type- 25 SFGP – 25 A, MAKE – CGL

S.

No.


1. Surface of

porcelain pole

insulator unit




Replace &

clean



15

S.

No.



temperature.

Gas pressure

5.0 kg/cm2 at

20 deg temp.

4. Heater,

thermostat &

lamp



Working &

setting of

thermostat is

25 – 30 deg. C



door, dust and hinges. Arrest the reason for

rain water and attend it.

Clean & apply

weather

sealant

material as per

annexure ‘V’



Replace, if required.

Replace

7. Shock observer Check oil leakage from shock observer.

Repair or replace, if required.

Replace

8. Control circuit




box.

Record voltage

and proper lug &

ferule

9. Local/Remote

switch

operation




Function properly

& tighten

connection

10. Limit switch &

auxiliary

contact




Function properly

11. Position of

indicator


12. Snap ring and

locking nut

Check tightness of snap ring and locking

nut. Tighten if required.

Tight



16

Sl.

No.



isolator.

Function

properly


& foundation



Tighten

3.2.11 25 kV Minimum Oil Interrupter

Type- HPGE7/9A, MAKE - ALIND

Sl.

No.


1. Surface of

porcelain pole

insulator unit




Replace &

clean

2. Bushing Check leakage of compound from top of the

bushing and take corrective action.

Attend


counter reading of BM:

-Before maintenance

- After maintenance

Function

properly

4. Position of

indicator

Check alignment and missing indicator In position

5. Operation of the

equipment on

local control

Check & attend abnormal sound, binding of

leverages or any rubbing of parts. Find out

the reason and attend it.

Attend



door, dust and hinges. Arrest the reason and

attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’

7. Shock absorber Check shock absorber function properly

during tripping.

Smooth function

8. Operation of

plunger

Check operation of plunger in closing &

tripping coil.

9. Oil level Check the oil level in the dashpot pole unit.

Top up, if necessary

Top up

10. Oil leakage Check for any oil leakage. Attend



17

Sl.

No.


11. Commutator of

motor

Check & clean commutator with clean dry

cotton cloth

Clean

12. Carbon brushes Check the condition of carbon brushes.

Replace, if worn out replace it.

Replace worn

out brushes

13. Local/Remote

switch operation

Check the operation of breaker on local and

remote switch. Breaker should have open &

close on selected position.

Function

properly

14. Interlocking Check the function of interlock with isolator. Function

properly

15. Earth

connections &

foundation



Tighten

3.2.12 25 kV SF- 6, Single Pole, Circuit Breaker

Type- LTB 72.5D1, MAKE - ABB

Sr.

No.


1. Surface of

porcelain pole

insulator unit




Replace & clean



Before maintenance

After maintenance

Function

properly


temperature.

Gas pressure 7.0

bar at 20° temp.

4. Heater,

thermostat &

lamp

Check function of heater, thermostat & lamp.

If any defect attend it.

Working &

setting of

thermostat is 25

– 30 deg. C



door, dust and hinges. Arrest the reason for

rain water and attend it.

Clean & apply

weather sealant

material as per

annexure ‘V’



Replace, if required.

Replace



18

Sr.

No.


Out

Remark

7. Shock observer Check the oil leakage from shock

absorber.

Repair or replaced, if necessary.

Replace

8. Local/Remote

switch operation




Function properly

9. Local and remote

switches


switch.

Function properly

10. Position of

indicator


11. Limit switch &

auxiliary contact




Function properly

& tighten

connection

12. Condenser

tripping device



Function properly

13. Anti pumping

device



Function properly


isolator.

Function properly


& foundation

Check & tighten the earth connections &


Tighten

3.2.13 Auxiliary Transformer

Type - Double wound, single phase, oil immersed

natural air cooled and step down

transformer for outdoor installation

Sl.

No.


1. Visual inspection

of transformer.

Check any sign of oil leakage, over heating. If

observe attend it.

Attend

2. Cleaning of

transformer

Clean the transformer externally conservator,

bushing and tank with clean cotton cloth.

Clean

3. Silica gel Check the condition of silica gel. If color is

pink reactivate/ replace.

Check oil in the cup of breather. Top up the

oil in cup if required.

Replace & top

up oil

4. Connections Check, clean & tight all connections of HT and

LT bushing terminals.

Tighten

5. Oil level in

conservator

Check & top up oil level in conservator with

new filtered oil up to mark, if required.

BDV of oil

more than 30

kV



19

Sl.

No.


6. AT enclosure Check & clean AT enclosure of vegetation and

other material.

Clean

7. Condition of pole

mounted ICDP

switch, control

panel and its

fuses

Check condition of pole mounted ICDP switch,

control panel and its fuses. Replace overheated

of lugs, fuses and tighten loose connections.

Use fuse wire

20 SWG for

34 Amp.

22 SWG for

24 Amp.

8. Caution board

and anti climbing

device

Check caution board and anti climbing device

for availability and conditions.

Available

9. Earthing

connections

Check & tight the earth connections. If found

loose.

Tighten

10. Arcing horn HV

bushing

Check flash mark on arcing horn. Attend if

flashover mark observe

Attend

3.2.14 220/132/25 kV Current Transformer

Type- Single phase, oil filled natural air cooled

Sl.

No.


1. Surface of

porcelain

bushing

Check damages, flash mark, chipping insulators

replace, if required. Clean with dry cotton cloth

for dirtiness.

Clean &

replace

2. Terminal

connectors

Check overheated/rusted terminal connectors.

Replace if any sign of overheated/rusted.

Replace

3. Terminal bolts,

nuts & washers

Check tightness of terminal bolts, nuts &

washers. Replace if any sign of

rusting/oxidation.

Replace

4. Oil level Check oil level for leakage. Top up oil if

required and arrest the leakage.

Attend

5. Earthing

connections


loose.

Tighten

6. Arching horn,

if provided

Check flash mark on horn tips. Clean flash

mark



20

3.2.15 220/132 kV Isolator

Type – Double pole, Triple pole

Sl.

No.


1. Isolator Check visually the conditions of the support

insulator. If observe any abnormality attend it.

Attend

2. Mechanism

& earthing

Check & clean mechanism, operation, tightness of

earthing connection and lubricate the moving parts.

Tighten &

lubricate

3. Operation of

Isolator

Check operation of the isolator for correct

adjustment of blade and smooth hand operation.

Free

movement

4. Interlock Check working of interlock without obstruction. Free

operation

5. Earthing

connections

Check & tight the earthing of the frame with its

fittings. Lead of earthing heel if provided

Tighten

3.2.16 25 kV Isolator

Type – Single pole, Double

Pole and Bipolar

Sl.

No.


1. Isolator Check damages, flash mark, chipping insulators

replace, if required. Clean with dry cotton cloth for

dirtiness.

Clean &

replace

2. HV

connections

Check & tight HV connections for overheated

/rusted. Replace if required.

Replace

3. Operation

of Isolator

Check the hand operation of the isolator for correct

adjustment of blade and smooth hand operation.

Free

movement

4. Interlock Check operation of interlock and lubricate all

moving parts.

Free

operation

5. Earthing

connections

Check & tight the earthing of the frame with its

fittings.

Tighten



21

3.2.17 198/120/42 kV Surge Arrester

Sl.

No.


1. Visual inspection of

lightning arrestor

Check sign of overheating if observe. Find

out the reason and attend it.

Attend

2. Surface of porcelain

bushing

Check damages, flash mark, chipping

insulators replaced, if required. Clean with


Clean &

replace

3. Surge counter, if

provided

Check & record the number of discharges of

surge counter, if meter is provided.

Record

3.2.18 Series Reactor (Oil Type)

Sl.

No.


1. Surface of

porcelain

insulator

Check damages, flash mark, chipping insulators

replaced, if required. Clean with dry cotton cloth

for dirtiness.

Clean &

replace

2. Reactor tank

and cover plate

Check & attend damages, oil leakage/ seepage.

Find out the reason and rectify.

Attend

3. Oil label Check & top up oil level in reactor with new oil

up to mark, if required.

BDV more

than 40 kV

of oil

4. Silica gel Check the condition of silica gel. If color is

pink reactivate/ replace.

Check oil in the cup of breather. Top up the

oil in cup if required.

Replace &

top up oil



22

Sl.

No.


5. Connection on

bushing

Check the tightness of bolts and nuts. Replace

the rusty or overheated bolts and nuts if

necessary.

Replace

6. Earthing

connections


loose.

Attend

7. Terminal

Connector &

Bus-bar

connectors

Check & tight the bolts and nuts of top & bottom

connectors. Replace the rusty or overheated bolts

and nuts if necessary.

Replace

8. Buchholz Relay Check for gas collection. In case gas is collected

the same should be sent for DGA.

As per

RDSO

guide line

for DGA

refer

Annex. 2.04

of ACTM

Vol II, Part

I.

3.2.19 Series Reactor (Dry Type)

Sl.

No.


1. Surface of

porcelain insulator


insulators replaced, if required. Clean with


Clean &

replace

2. Connection on

bushing

Check the tightness of bolts and nuts.

Replace the rusty or overheated bolts and

nuts if necessary.

Replace

3. Earthing

connections


loose.

Attend

4. Terminal

Connector & Bus-

bar connectors

Check & tight the bolts and nuts of top &

bottom connectors. Replace the rusty or

overheated bolts and nuts if necessary.

Replace

5. Coil Check visually of coil for warm. If warm find

out the reason and attend it.

Attend



23

3.2.20 Control and Relay Panel

Sl.

No.


1. Cleaning of

panel

Check & clean accumulated dust externally &

internally with dry cloth.

Clean

2. Indicating and

recording

instrument

Check all indicating and recording instrument

are working normally.

Working

normally

3. Relay Check & clean outer terminals of relay for any

abnormality.

Intact

4. Cable

connections

Check & tighten all cable connections, if found

loose.

Tighten

5. Terminal

board

Check & clean terminal board, cable damage

and cable leads with dry cotton cloth and attend

the damage cable.

Attend

6. Fuses Check all fuses for proper rating &

overheating, replace if necessary. Proper rating

7. Earthing

connections


loose.

Attend

8. Doors Check doors & hinges for intactness. Free

movement

9. Holes in panel Check & plug the holes to avoid entry of

moisture and insects.

Free from

holes

3.2.21 Battery Charger

Sl.

No


1. Carry out following work in addition to fortnightly schedule

2. Charger Check & clean the charger outside and

inside with dry cloth.

Clean

3. Voltmeter &

Ammeter

Check the proper function of voltmeter &

ammeter.

Working

satisfactory

4. Overheating Check any sign of overheating inside the

charger. Find out the reason and attend it.

Attend



24

3.2.22 25 kV Motorised Isolator

Type – Single Pole

Sl.

No.


1. Visual Visual checking of isolator for any

abnormality.

No

abnormality

2. Control box

Check & clean interior with dry cloth or

vacuum cleaner. Remove accumulated dust,

Plug the holes to avoid entry of moisture and

repair or replace the rusted parts.

Clean



25

3.3 QUARTERLY SCHEDULE


Sl.

No.


Out

Remark

1. Carry out following work in addition to monthly schedule.

2. Bus bars, clamps

& connectors by

thermo vision

camera

Check nut, bolt & washers for

overheating. Replace, if necessary.

Replace


Type- Double wound, single phase, oil immersed natural air cooled and step down


Sl.

No.



2. Drop Out

(DO) fuse

Check condition of DO fuse barrel and fuse

element. Replace the breakage, overheating and

non standard fuse wire.

Use

standard

fuse wire

3. Sound of

equipment

Check any unusual sound of equipment.

soundless

3.3.3 25 kV Potential Transformer

S.

No.


1. Inspection of

PT

Check oil leakage, chip or insulator broken and

any sign of overheating, if observe attend it.

Attend

2. Terminal Check any overheating of terminal. Replace if

found overheated.

Replace



26

S.

No.


3. Terminal

bolts, nuts &

washers

Check & replace of terminal bolts, nuts and

washer. If found any sign of rusting/oxidation.

Replace

4. Oil level Check oil level in PT& top up with new oil up to

mark, if required.

BDV of oil

more than

40 kV

5. Fuse Check fuse and neutral link for proper rating and

tightness. Replace the fuse if necessary.

Replace

6. Earthing

connections


loose.

Attend

3.3.4 25 kV Motorised Isolator


S.

No.


1. Carry out following work in addition to monthly schedule

2. Door gasket

and hinges

Check weather proof gasket & hinges

for good condition. Replace/ repair, if

damage.

Replace/rep

air

3. Manually

operation

Check the operation manually in local and

remote, keeping the control door open.

Observe whether the mechanism and operating

rod functions smoothly without any rubbing or

obstruction.

Smooth

operation

4. Electrically

operation

Check the operation electrically in local and

remote, keeping the control door open.

Observe whether the mechanism and operating

rod functions smoothly without any rubbing or

obstruction.

Smooth

operation

5. Wiring

connection

Check & tight wiring connections for loose,

overheating or any defect.

Attend

6. Relays and

contactors

Check & clean healthiness of relays,

contactors and its contacts.

Functioning

7. Heater Check working condition of heater, if

defective attend it.

Functioning

8. Grease and

lubrication

Check & clean and apply grease and lubricate

to all moving parts.

9. Earthing

connections


loose.

Attend

10. Locking

arrangement

Check working of locking arrangement

smoothly.

Smooth

functioning



27


Sl.

No.



2. Earthing terminal

& earthing strip

Check & tight earthing terminal & strip, tighten

if loose.

Attend

3. Guarding ring, if

provided

Check guarding ring connections, tighten if

loose.

Attend

3.3.6 Capacitor Bank (TI/MI/00026 Rev. 2)

Type- Single phase, oil filled natural air cooled.

Sl.

No.


1. Surface of

porcelain insulator


insulators replaced, if required. Clean with dry

cotton cloth for dirtiness.

Clean &

replace

2. Dielectric Check dielectric leakage/ seepage

If leakage/seepage is found :

i. Minor seepage may be attended by M-seal

(fast drying type compound).

ii. Extent of leakage may be studied, attend it

or replace it.

Attend

or

replace

3. Birdcage in and

around the traction

sub station

Check & remove birdcage in and around the

traction substation to avoid bird electrocution.

Free from

birdcage

4. Temperature of the

capacitor units

Check physically for any abnormal

temperature rise of the capacitor units. If

abnormal temperature rise of the capacitor

units. Find out the reason and rectify.

Attend


Sl.

No.


1. Carry out following work in addition to fortnightly & monthly schedule.

2. Terminal

connection

Check the terminal connection on the

disconnecting link. Replace any overheating of

terminal connectors, if found overheated or

rusted.

Replace



28

Sl.

No.


3. Earth terminals Check & tight the earth connections. If found

loose.

Attend

4. MCB Check visual operation for proper functioning

and rating.

Smooth

operation

5. Three pin plug

with socket

Check & replace overheating or defective three

pin plug/ socket.

Replace

6. Termination

ends of the

cable

Check & tight all termination ends of the cable,

if loose.

Tighten

3.3.8 AC/ DC Distribution Panel

S.

No.


1. Distribution

panel

Check & clean the panel outside and inside

with dry cloth.

Clean

2. Voltmeter Check the function of voltmeter. working

satisfactory

3. Earth terminals Check & tight earth termination points on both

ends. Attend if any deficiency.

Attend

4. MCB Check visual operation for proper functioning

and rating.

Smooth

operation

5. Temperature at

termination

points

Measure & record the temperature at

termination points. If variation is more than 5

deg. with room temp, ensure the tightness.

Measure and

record

6. LED Check & replace the defective LED with tested

LED.

Replace

7. Fuses Check all fuses for proper rating & overheating,

replace if necessary.

Proper rating

8. Holes in panel Check & plug the holes to avoid entry of

moisture and insects.

Free from

holes



29

3.4 HALF YEARLY SCHEDULE


S.

No.


1. Carry out following work in addition to monthly and quarterly schedule.

2. Fencing Inspect all around switching station to

observe any abnormality. If seen attend the

same.

Attend

3. Door and bonding

between metal

fencing panels and

earth, lubricant the

door

Check hinges of all doors and bonding

between metal fencing panels and earth.

Lubricant the hinges of all doors.

If bonding deficient metal fencing panels and

earth, attend it.

Intact all

respect &

lubricate

4. Boards Check & painting of all caution, danger

board, shock treatment, schematic diagram,

key box and other boards, if faded.

Replace or

enamel

paint

5. Fire extinguisher,

buckets, first aid

boxes

Inspect expiry date of fire extinguisher,

buckets fill with sand, first aid boxes fill with

necessary medicine with valid date.

Intact all

respect

6. Oil sump, if

available

Check & clean oil sump for dirtiness. Clean




2. Test oil

sample with

oil test kit.

Test for BDV and acidity. Compare and

take action as indicated in enclosed

ANNEXURE-I

Sample should

be taken

moving oil.

3.

Insulation

resistance of

winding and

polarization.

Index (PI)

with 2.5 kV

or 5 kV

megger for

HV-LV

HV-E

LV-E.

Insulation resistance is to be measured for

10 sec., 60 sec. and 600 sec. for HV-LV,

HV-E and LV-E. Calculate PI (Polarization

index) by the IR ratio of R60/R10 and

R600/ R60

Insulation resistance values should be

compared with the last recorded value.

Compare PI values with values at the

time of commissioning/ last recorded.

PI Insulation/ condition

< 1.0 Dangerous

1.0 - 1.1 Poor

1.1- 1.25 Questionable

1.25 - 2.0 Satisfactory

>2.0 Good

If PI value is less than 1.1, oil should be

filtered. In case the value does not

improve even after filtrations periodic

overhauling should be under taken.

Ensure that

transformer

is

disconnected

Ensure

bushings are

clean and

free from

moisture and

temperature

on which IR

is recorded



30


4. PRD/

explosion

vent

Check & investigate for operation of PRD/

explosion vent for any damage and

presence of oil. Check connection and

operation of PRD/ explosion vent. Replace

the damage PRD with new PRD.

Replace the

damage PRD





Sl.No. Item Inspection And Work To Be

Carried Out

Remark


2. All the moving

part of the

mechanism

Check, clean & lubricate the gear,

bearing cum shaft rollers and

latches.

Lubricate as per

annexure ‘VI’

3. All cir clip, split

clip and dowel pin

Check for availability and

damages. Replace, if damage.

Replace

4. Spring stroke Measure & record spring stroke

contact pressure.

Minimum 4 mm and 5

mm max.

5. Contact wear

indication

Check contact wear mark. If green

not seen, contacts are worn off.

Change bottle or

contact manufacturer.

6. Insulation

Resistance of pole

unit (when

breaker in open

position)

Check & record IR value of pole

unit as per OEM:

i Top-Bottom

ii Top- Earth

iii Bottom - Earth

Check with 2.5/5.0 kV megger.

-More than 5000 MΩ

-Record the make &

serial number of

megger.

7. Insulation

Resistance of pole

unit (when

breaker in close

position)

Check & record continuity & IR

value of pole unit as per OEM:

i. Top-bottom –for continuity

ii. Top & bottom - earth

Check with multimeter & 2.5/5

kV megger.

-Continuity zero

-More than 5000 MΩ

-Record the make &

serial number of

megger.

8. Insulation

Resistance of

i. Motor

ii. Closing coil

iii. Tripping coil

iv.AC& DC wiring

Check & record IR value of:

i. Motor

ii. Closing coil

iii. Tripping coil

iv. AC wiring & DC wiring

Check with 500 V megger

i. Motor – 2 MΩ

ii. Closing coil -2

MΩ

3.. Tripping

coil -2 MΩ

iv. AC & DC wiring

more than 2 MΩ

9. Motor, if

applicable

Check carbon brushes & clean

commutator. Replace carbon

brush if worn out.

Replace the brush

10. Top cover Check sealing of top cover for any

moisture trapping. Ensure

Sl.No. Item Inspection And Work To Be Remark



31

Carried Out

11. Wipe & Travel

measurement

Measure & record the wipe &

travel measurement as per

OEM.

Record

ALIND CB Wipe 8+/-0

Travel 22+2/-0

BM Wipe 8+1/-0

Travel 21+1/-0

BHEL BM Wipe 10

mm

Travel 22to2

4

ABB CB/BM Wipe 25+2/-

0

Travel

3.4.4 132 Kv SF-6 Circuit Breaker

Type – 120 SFM – 32B, Make – CGL

Sl.No. Item Inspection And Work To Be Carried

Out

Remark


2. All the moving

part of the

mechanism


bearing cum shaft rollers and latches.

Lubricate as per

annexure ‘III’

3. Insulation

Resistance of

pole unit (when

breaker in open

position)

Check & record IR value of pole unit:

i Top-Bottom

ii Top- Earth

iii Bottom – Earth

Check with 2.5/5.0 Kv megger.

-More than 1500

MΩ

-Record the make &

serial number of

megger.

4. Insulation

Resistance of

pole unit (when

breaker in close

position)

Check & record continuity & IR value

of pole unit as per OEM:

i Top-bottom – for continuity

ii Top & bottom – earth

Check with multimeter & 2.5/5.0 kV

megger.

-Continuity zero

-More than 1500

MΩ

-Record the make &

serial number of

megger.

5. Insulation

resistance

between control

circuit to ground

Measure & record the insulation

resistance between control circuits to

ground by 500 V megger.

More than 2 MΩ

Record the make &

serial number of

megger.

6. Closing coil Check & record closing coil parameter:

i. Voltage

ii. Resistance

iii. I R Value

Check with measuring instrument (

megger & multimeter)

i. Voltage 110V

DC+/- 10%

ii. Resistance 32

ohm

iii. IR Value 2 MΩ

Sl.No Item Inspection And Work To Be Remark



32

Carried Out

7. Trip coil Check & record trip coil parameter:

i. Voltage

ii. Resistance

iii. I R Value

Check with measuring instrument(

Megger & multimeter)

i. Voltage 110V

DC+/- 10%

iii Resistance 32

ohm

iii. I R Value 2 MΩ

8. Mechanism box Check penetration of rain water, rust

and door hinges. Arrest the reason

and rectify.

Weather sealant as

per annexure ‘V’

9. Main terminal

connector

Check overheated & rusted nuts,

bolts, washers and bimetallic strips.

Replace if required.

Replace and use

conducting

compound

10. Shock absorber Check for oil leakage, if leakages

attend it.

Attend or replace

11. Charging time

of closing spring

Check & record charging time of

closing spring.

15 Sec.

3.4.5 25 kV SF-6 Circuit Breaker (GCB)

TYPE- 50 SFGP – 20A, Make CGL

Sl.No. Item Inspection And Work To Be

Carried Out

Remark


2. All the moving

part of the

mechanism

Check, clean & lubricate the linkage

in SF 6 gas & air mechanism.

Lubricate as per

annexure ‘III’

3. Insulation

Resistance of

pole unit (when

breaker in open

position)

Check & record IR value of pole unit

as per OEM:

i Top-Bottom

ii Top- Earth



More than 10,000 M

Ohms

Record the make &

serial number of

megger.

4. Insulation

Resistance of pole

unit (when breaker

in close position)




ii Top & bottom – earth


megger.

-Continuity zero

-More than 10,000

MΩ

-Record the make &

serial number of

megger.

5. Insulation

resistance

between control

circuit to ground



ground with 500 V megger.

More than 2 MΩ

Record the make &

serial number of

megger.

6. Tripping trigger

& roller

Check, adjust & record the gap

between tripping trigger & roller.

Within 0.3 to 0.7

mm. and record.

7. Gas pipe line Check pipe line & joints by gas

detector or soap water for leakage.

Attend



33

Sl.No Item Inspection And Work To Be

Carried Out

Remark

8.

Mechanism box Check penetration of rain water, rust

and door hinges. Arrest the reason

and rectify.

Weather sealant as

per annexure ‘V’

9. Main terminal

connector

Check overheated & rusted nuts,

bolts, washers and bimetallic strips.

Replace if required.

Replace and use

conducting

compound

10. Spring charging

motor

Check & clean commutator, carbon

brushes size and spring tension, free

movement of motor, temperature and

lubricate. Replace bearing if jam.

Attend


Type – 70 SFM – 32 A, MAKE – CGL

Type – 120 SFM – 32 A, MAKE – CGL

Sl.

No.


Out

Remark


2. All the moving

part of the

mechanism



Lubricate as per

annexure ‘III’

3. Insulation

Resistance of

pole unit (when

breaker in open

position)

Check & record IR value of pole unit as

per OEM:

i Top-Bottom

ii Top- Earth



-More than 1500

MΩ

-Record the make

& serial number

of megger.

4. Insulation

Resistance of

pole unit (when

breaker in close

position)

Check & record continuity & IR value of

pole unit as per OEM:

iii Top-bottom – for continuity

iv Top & bottom – earth


megger.

-Continuity zero

-More than 1500

MΩ

-Record the make

& serial number

of megger.

5. Insulation

resistance

between control

circuit to ground




-More than 10

MΩ

-Record the make

& serial number of

megger.

6. Closing coil Check & record closing coil parameter:

i. Voltage

ii. Resistance

iii. I R Value

Check with measuring instrument

(magger & millimeter)

i. Voltage

110V DC+/- 10%

ii. Resistance 20Ω

iii. IR Value 2 MΩ



34

Sl.

No.


Out

Remark

7. Motor for air

compressor





Replace worn out

carbon brushes &

jam bearing

8. Consumption of

air to open the

breaker

Check & record air pressure drop in one

operation. Create one operation and

check.

Drop less than 1.2

kg/cm2 and record


Type -ELF SL- 4 - 1 Double Pole, MAKE – ABB

Sl.

No.


Out

Remark


2. All the moving

part of the

mechanism



Lubricate as per

annexure ‘VI’

3. Insulation

Resistance of

pole unit (when

breaker in open

position)


as per OEM:

i Top-Bottom

ii Top- Earth

iii Bottom - Earth


- More than 2000

MΩ

- Record the make

& serial number

of megger.

4. Insulation

Resistance of

pole unit (when

breaker in close

position)




ii Top & bottom - earth

Check with multimeter & 2.5/5 kV

megger.

-Continuity zero

- More than 2000

MΩ

- Record the make

& serial number

of megger.

5. Insulation

resistance

between control

circuit to ground


resistance between control circuit to

ground by 500 V megger.

- More than 2 MΩ

- Record the make

& serial number

of megger.

6. Compressor

setting

Check & record auto start / cut off

compressor setting.

-Governor switch

ON-19.5 bar

-Governor Switch

OFF-20.5 bar

7. Motor for air

compressor





Attend

8. Air pressure drop Check & record air pressure drop in

one operation. Create one operation and

check.

Drop maximum 1.0

bar.



35

Sl.

No.


Out

Remark

9. Air pressure

charging

Check & charging of time for pressure.

Measure the timing 0 bar to 20.5 bar.

Less than 75

minutes for 200 lit.

air reservoir

10. Air and gas pipe

line

Check pipe line & joints leakage of air

& gas by soap water for air and gas for

gas detector or soap water.

Attend

3.4.8 25 kV SF- 6 Circuit Breaker/Interrupter

Type - SF-6 EDF SK-1-1 (S), MAKE – ABB

Type - SF-6 EDF SK-1-1, MAKE – ABB

Sl.

No.


Carried Out

Remark


2. All the moving

part of the

mechanism



Lubricate as per

annexure VI & VII

3. Insulation

Resistance of pole

unit (when

breaker in open

position)


as per OEM:

i Top-Bottom

ii Top- Earth

iii Bottom - Earth


- More than 2000

MΩ

- Record the make

& serial number

of megger.

4. Insulation

Resistance of pole

unit (when

breaker in close

position)



i. Top-bottom – for continuity

ii. Top & bottom - earth


megger.

-Continuity zero

- More than 2000

MΩ

- Record the make

& serial number

of megger.

5. Insulation

resistance between

control circuit to

ground




- More than 2 MΩ

- Record the make

& serial number

of megger.



Attend

7. Spring charging

motor





Replace worn out

carbon brushes &

bearing

8. Charging time of

spring

Check & record time for charging the

spring at nominal tension

Not more than

15sec.



36

3.4.9 25 kV SF- 6, Interrupter (Single, Double Pole)

TYPE- 30 SFGP – 25 A, MAKE - CGL

TYPE- 25 SFGP – 25 A, MAKE – CGL

Sl.

No.


Carried Out

Remark


2. All the moving

part of the

mechanism


bearing cum shaft rollers and

latches.

Apply lubricate as

per annexure ‘III’

3. Insulation

Resistance of

pole unit (when

breaker in open

position)

Check & record IR value of pole unit as per OEM:

i.Top-Bottom, ii. Top- Earth, iii. Bottom - Earth

Check with 2.5 kV megger.

30 SFGP – 25 A

More than 10,000

MΩ & record the

make & serial

number of megger.

25 SFGP – 25 A

More than 500 MΩ

& record the make &

serial number of

megger.

4. Insulation

Resistance of

pole unit (when

breaker in close

position)

Check & record continuity & IR value of pole unit as per

OEM: i.Top-bottom – for continuity, ii.Top & bottom -

earth

Check with multimeter & 2.5/5 kV megger.

30 SFGP – 25 A

-Continuity zero

-More than 10,000

MΩ & record the

make & serial

number of megger.

25 SFGP – 25 A

-Continuity zero

-More than 500 MΩ

& record the make

& serial number of

megger.

5. Insulation

resistance

between control

circuit to ground




More than 2 MΩ

Record the make &

serial number of

megger.

6. Tripping trigger

& roller

Check, adjust & record the gap

between tripping trigger & roller.

Between 0.3 to 0.7

mm. and record.



Attend

8. Mechanism box Check penetration of rain water,

rust and door hinges. Arrest the

reason and rectify.

Apply weather

sealant as per

annexure ‘V’



37

Sl.

No.


Carried Out

Remark

9. Spring charging

motor



movement of motor, temperature

and lubricate. Replace bearing if

jam.

Attend



Sl.

No.


Carried Out

Remark


2. Insulation

resistance of pole

unit (when breaker

in open position)

Check & record IR value of pole

unit:

i Top-Bottom

ii Top- Earth

iii Top & Bottom - Earth


More than 1000

MΩ

Record the make &

serial number of

megger.

3. Insulation

Resistance of pole

unit (when breaker

in close position)



i Top-bottom – for

continuity

ii Top & bottom - earth

Check with multimeter & 2.5/5.0

kV megger.

-Continuity zero

-More than 1000

MΩ

-Record the make &

serial number of

megger.

4. Insulation

resistance between

control circuit to

ground


resistance between control

circuit to ground with 500 V

megger.

More than 2 MΩ

Record the make &

serial number of

megger.

5. Test the oil sample Take oil sample from the pole,

before and after monsoon and

test the dielectric strength

(BDV) and excessive presence

of carbon. If BDV is low or

excessive presences of carbon in

oil then replace the oil with fresh

dry and tested oil.

BDV - 40 kV Min.

6. Arc quenching

chamber

Check condition & clean arc

quenching chamber with dry

cloth for its condition

No abnormality

7. Latches Check & lubricate all latches Lubricate

8. Spring charging

motor

Check & clean commutator,

carbon brushes size and spring

tension, free movement of

motor, temperature and

lubricate. Replace bearing if

jam.

Attend



38



Sl.

No.


Carried Out

Remark


2. All the moving

part of the

mechanism



Lubricate as per

annexure ‘VI, &

‘VII’

3. Insulation

Resistance of pole

unit (when

breaker in open

position)


as per OEM:

iv Top-Bottom

v Top- Earth

vi Bottom - Earth


- More than 2000

MΩ

- Record the make

& serial number

of megger.

4. Insulation

Resistance of pole

unit (when

breaker in close

position)



iii. Top-bottom – for continuity

iv. Top & bottom - earth


megger.

-Continuity zero

- More than 2000

MΩ

- Record the make

& serial number

of megger.

5. Insulation

resistance between

control circuit to

ground




- More than 2 MΩ

- Record the make

& serial number

of megger.



Attend

7. Spring charging

motor





Attend

8. Charging time of

spring

Check & record time for charging the

spring at nominal tension

Not more than

15sec.


TYPE- Double wound, single phase, oil immersed natural air cooled and step down


Sl.

No.


Carried Out

Remark

1. Check all points stated carried out in monthly and quarterly schedule

2. BDV of oil Take sample of oil from bottom

of tank and check the BDV of

oil with BDV tester.

BDV more than 30 kV (with

2.5 mm spindle gap)

3. Additional

arching horn

on fixed 9-

ton insulator

Check flash mark on arching

horn and measure the gap of

arching horn.

Gap maintain 165 mm (min)

& record



39

Sl.

No.


Carried Out

Remark

4. Measure & record insulation resistance between

5. HV- Earth 200 M ohm. Minimum (use 2.5 kV megger)

6. HV- LV 200 M ohm. Minimum (use 2.5 kV megger)

7. LV- Earth 2 M ohm minimum (use 500 V megger)

8. Earth

resistance

Check earth connections,

measure & record the earth

resistance by earth tester.

- Not more than 10 ohm.

- Record the make & serial

number of megger.

9. LT cable Check & replace damage,

overheating of wires, lugs

etc.of LT cable. Measure &

record IR value of cable:

i. i. Between AT to ICDP switch.

ii. Between ICDP switch to

control panel by 500 V

megger.

2 M ohm min. at 30

deg.tempreture and record


Sl.

No.


Carried Out

Remark

1. Check all points stated carried out in quarterly schedule

2. Measure Insulation Resistance between:

3. HV- Earth, if possible 200 M ohm. Minimum (use 2.5 kV megger)

4. HV- LV 200 M ohm. Minimum (use 2.5 kV megger)

5. LV- Earth 2 M ohm minimum (use 500 V megger)

6. Rod gap, If provided Check & record rod gap setting Record

3.4.14 220/132/25 kV Current Transformer Type- Single phase, oil filled natural air cooled

Sl.

No.


1. Check all points stated carried out in monthly schedule

2. Earth link Check & tight earth link in secondary box. Ensure for

tightness

3. Measure Insulation Resistance between:

4. HV- Earth i. 2000 MΩ min. for 220/132 kV (use 2.5 kV megger)

ii. 200 MΩ min. for 25 kV (use 2.5 kV megger)

HV- LV i. 2000 MΩ min. for 220/132 kV (use 2.5 kV megger)

ii. 200 MΩ min. for 25 kV (use 2.5 kV megger)

LV- Earth i. 200 MΩ Min. for 220/132 kV (use 2.5 kV megger)

ii. 2 MΩ min. for 25 kV (use 500 V megger)



40

Sl.

No.


5. Fuses Check fuse for proper rating & overheating,

replace if necessary.

Proper

rating

6. Arching horn, if

provided

Check arching horn for flash mark and measure

the gap of arching horn.

record

3.4.15 220/132 kV Isolator


Sl.

No.



2. Isolator Check damages, flash mark, chipping insulators

replace, if required. Clean with dry cotton cloth

for dirtiness.

Clean &

replace

3. Small parts Check all nuts, bolts, split pins for good

condition. Replace if rusted or defective

Replace

4. Jaws Check the spring of jaws for proper gripping. Intact

5. Main contacts Check overheating and clean main contacts and

lightly wipe with petroleum jelly.

Apply

petroleum

jelly

6. Articulated

joints, sliding

and bearing

surface

Check & clean all articulated joints, sliding and

bearing surface with kerosene oil and lubricate.

SAE 40

7. Interlock Check operation of interlock and lubricate all

moving parts.

Free

operation

8. Arcing horn, if

provided

Check arcing horn for correct alignment.

Working satisfactory, if provided

Proper

alignment

9. HV connections Check & tight HV connections for overheated

/rusted. Replace if required.

10. Earthing of

operating handle

Check earthing of operating handle with copper

flexible wire.

Intact


Type – Single pole, Double pole and Bipolar

Sl.

No.



2. Main contacts Check overheating and clean main contacts and

lightly wipe with petroleum jelly.

Apply

petroleum

jelly

3. Small parts Check all nuts, bolts, split pins for good

condition. Replace if rusted or defective

Replace



41

Sl.

No.


4. Simultaneous

operation of

blades (double

pole)

Check & simultaneous operation of blade for

correct alignment. If variation adjust it.

Proper

alignment

5. Locking

arrangement

Check the condition of locking arrangements to the operating handle and provision of padlocks.

Pad lock

available

6. Arcing horn, if

provided

Check arcing horn for correct alignment. Working

satisfactory, if provided

Proper

alignment

7. Earthing of

operating handle

Check earthing of operating handle with copper

flexible wire.

Intact

3.4.17 Motorised Isolator, 25 kV Type – Single Pole


RDSO (TI/SPC/PSI/CLMNA/0030)

Sl.

No.

Item Inspection And Work To

Be Carried Out

Remark

1. Carry out following work in addition to monthly & quarterly schedule

2. Leakage current ,

if monitor

provided

Measure & record of leakage

current

Less than 500 Micro Amps

as per speciation no

TI/SPC/PSI/CLMNA/0030

Sl.

No.


3. Carry out following work in addition to quarterly schedule

4. Clearance of

blades in open

condition

Check, measure & record the distance between

male and female contact in fully open position.

Minimum 500

mm

5. Electrical

operation

Check the isolator for smooth operation and

correct alignment of male & female contacts.

Contact

properly

6. Alignment of

isolator

Check the correct alignment of isolator for its

firm grip while isolator in closed condition.

Attend if required.

Firm grip

7. Limit switches,

auxiliary

switches &

contacts

Check & clean limit switches, auxiliary

switches & contacts and function.

Functioning

8. Blade tips and

contact fingers

Check blade tips for overheating and contact

fingers and apply petroleum jelly on the contact

surface

Apply jelly



42

3.4.19 25 kV Capacitor Bank (TI/MI/00026 Rev. 2)


Sl.

No.


1. Carry out following work in addition to quarterly schedule

2. Tension on

connections

Check & release the excessive tension on the

connections. If required

Tension free

3. Corrosion on

metallic parts

Check & clean rust collection/corrosion mark

on the metallic part by cleaning agent.

Clean

4. Current and

voltage variation

Check, measure & record current and voltage

variation for the capacitor bank for at least 24

hrs and record.

Record


Sl.

No.



2. BDV of oil Take sample of oil from bottom of tank and

check BDV with BDV tester. If low replace the

oil with fresh filtered oil

BDV more than

40 kV (with 2.5

mm rod gap).

3. Insulation

resistance

of winding

Measure & record insulation resistance:

Winding to earth (ambient temp also to be

recorded) with 2.5 kV megger.

Minimum 200 M

ohms


Sl.

No.



2. Indication and

recording

instrument

Check all indication and recording instrument

for healthiness. Replace if defective.

All

functioning

3. Relay Check & clean outer terminals of relay. Intact

4. Door gasket &

hinges

Check & replace gasket for damages. Replace

with new if necessary.

Replace

5. All connections Check & tight all connection. Tighten if loose Tighten



43

3.4.22 Condition Based Maintenance through Thermo vision Camera (Traction Substation)

28th MSG TRD at SCR on Feb 2011 item no. 28.19

1. AC TRD (Traction Sub- Station)

Sl.

No.


Carried Out

Remark

1. (For DC) Rectifier

Panel, Incoming &

out going bus

bar/cable

termination.

-Check thermal scanning by thermo

vision camera.

-The temperature of hot spots is

compared with adjacent/nearby

similar components.

Variation in

temperature

following action

is to be taken:

i. Variation > 20

deg.-To be

attended

within 24 hrs

ii. 10 deg. <

variation < 20

deg. To be

attended

within 10 days

iii. 5 deg. <

variation < 10

deg. To be

attended

within a

month

iv. Variation < 5

deg. Normal

2. Cable Termination of

cable isolators ends

connection


vision camera.



similar components.

3. All joints,

connections

terminals, jumpers,

PG clamps of

incoming switch

yard and out going

switch gear


vision camera.



similar components.

4. Transformer bushing

connection


vision camera.



similar components.

5. Bus bar joints


vision camera.



similar components.

6. LA, CT, PT

connections from bus

bar and PG clamps.


vision camera.



similar components.

7. HV side bi-polar

isolators, Single pole

isolator contact and

bus bar.


vision camera.



similar components.

8. Power cable

terminations and

joints provided in

sub-stations.


vision camera.



similar components.



44

3.4.23 Earthing & Bonding

Sl.

No.


Out

Remark

1. Bonding &

earth connection

with structure

Check physically soundness & tightness

of bonding & earth connection with

structure, lightning arrestor, and electrical

equipment inter panel connection.

Intact

2. Earth resistance

of electrical

equipment

body, fencing

and structure

with electrode

Measure & record the earth resistance of

electrical equipment body, fencing,

structures by earth tester.

-Less than 10 ohms

-Record the make

& serial number of

megger.

3. Shielding wire Check termination of shielding wire

condition and bonding with structures.

Intact

4. Earth resistance

of each

electrode after

disconnection


each electrode after disconnecting it from

common earth system by earth tester.

-Less than 10 ohms

-Record the make

& serial number of

megger.

5. Combined earth

resistance of

TSS/SP/SSP

with rail


combined electrode without

disconnecting it from common earth

system by earth tester.

For TSS < 0.5

and SP and SSP <

2.0


Sl.

No.


1. Carry out following work in addition to monthly and quarterly schedule

2. Equipments and

wire

Check and clean equipments and wires with

soft wire brush.

Clean

3. Electrolyte

condenser

Visual checking. If observe abnormality then

replace it.

Replace

4. i. Rectifier,

ii. Coarse/ fine

control switch,

iii. Trickle/Boost

change over

switch

Check & tight connection of all terminal

connectors and working:

i. Rectifier,

ii. Coarse/fine control switch

iii. Trickle/Boost change over switch

working

smoothly



45

3.4.25 AC/DC Distribution Panel

Sl.

No.


1. Carry out following work in addition quarterly schedule

2. Panel Check & Clean the panel inside and outside by

soft brush.

Clean

3. MCB, rotary

switches

Check and clean smooth operation & working

without obstruction.

Working

satisfactory

4. Tightness Check & tight cable termination of MCBs, rotary

switch and bus bar.

No loose

connection

3.5 YEARLY SCHEDULE


Sl.

No.


1. Carry out following work in addition to monthly, quarterly and half yearly schedule

2. Building Check for roof cleaning, leakage and condition

of building. Complain to civil dept, if any

deficiency.

Attend

3. Lightning screen Check & tight strain clamp of wire. If observe

any defect attend it.

Attend

4. Structure and

fencing

Check structure and fencing for soundness.

Intact

5. Trenches Open and clean trenches for possibility of

lizard and other insects entry in control panels /

equipments.

Clean

6. Tree & branches Check & prune the tree branches near to live

conductor as required.

Maintain

clearance


Sl.

No.


Carried Out

Remark

1. Carry out following work in addition to monthly & half yearly schedule:

2. Transformer

tank, bushings,

taps changer,

radiator and

connection joints

Check infrared temperature scanning.

Infrared temperature scanning is to

be done preferably at the time of full

load to find any over heating.

The infrared scan

results are compared

with previous results

3. OIP condenser

bushing

Measure, record & compare the test

for Tan-delta, capacitance and IR

(Shearing bridge may be used for tan

delta & capacitance). Compare with

earlier value. In case of deviation in

reading from standard value, replace

or consult manufacturer.

- Bushing should be

cleaned for dust and

moisture.

- Test should be done

on sunny day.

- Max allowable Tan-

delta is 0.007

- Max allowable

capacitance 110%



46

Sl.

No.


Out

Remark

4. Gasket joints of

transformer

Check & tight the bolts evenly to avoid

uneven pressure in case of leakage

only.

Tightening of the bolts

has to be done in

proper sequence

5. Rod gap setting

of bushing

Check rod gap setting. Adjust if

required

6. Test oil in

transformer

Test oil as per the ANNEXTURE -1

The oil sample is tested as per conform

to IS-1866-2000. If the oil value does

not meet the requirement oil to be

replace.

Replace with new oil.

Refer Annexure-I

giving Annexure-2.03

B of ACTM Vol. II,

Part-I (As per latest IS

1866-2000)

7. Dissolved gas

analysis (DGA)

on oil

Oil sample taken for DGA as per

RDSO guide line at Annexure 2.04 of

ACTM Vol.-II Part-I.

Test result compare with the RDSO

guideline and action taken accordingly.

Refer Annexure 2.04

of ACTM, Vol.II, Part

I. in case of abnormal

DGA values in the

past, DGA test has to

be done frequently i.e.

every six-months

8. Working of tap

changer switch

Move the tap setting switch up and

down full range so that by self-wiping

action good contacts are assured.

Set the tap finally at

the correct position

9. Relays, alarm &

their circuits

Check relay and alarm contacts, their

operation, fuses etc. and relay

accessories.

Clean the components, replace contacts

and fuses if necessary. Change the relay

setting if necessary.

Operation & setting

10. Control boxes &

Terminal boxes/

cable

Check for water tightness of boxes &

terminal boxes. Replace gasket, if

required.

Replace

11. Temperature

indicators

Check for pockets, holding

thermometer oil to be replenished, if

required.

Attend

12. Dial type oil

gauge

Check pointer for free movement.

Adjust, if required.

Attend

13. Earth resistance Measure & record earth resistance by

earth tester. Take suitable action, if

earth resistance is high.

-Less than 10 ohms

-Record the make &

serial number of

megger.

14. Buchholz relay Check operation and measure the

insulation resistance by 500V megger

and continuity test for contacts with

test lock screw set as 5°.

IR not less than 20

mega ohm.

On continuity test

relay shall operate.

15. Voltage ration

test with wheat

stone bridge,

voltmeter

Precautions to be taken as per normal

practice being followed for

measurements with wheat stone bridge.

Compare the trends of the ratio with

reference to pre commissioning/ factory

value/ earlier test.

The sudden variation

in ratio from the last

measured value should

call for further

investigation.



47

Sl.

No.


Out

Remark

16. Winding

resistance test

with wheat stone

bridge voltmeter

– ammeter

The test conducted on principal tap by

applying DC current. The measured

value should be converted to 75°C for

conversion.

Compare the value with the pre-

commissioning/ factory test values.

Deviation in absolute value should be

less than ± 5% of pre-commissioning or

factory set value.

This test shall be last

test on winding to

avoid DC flux

remaining in core

resulting incorrect

values in the other

test.





Sl.

No.


1. Carry out following work in addition to monthly & half yearly schedule

2. Auxiliary

switches

connected in

conjunction with

mechanism

Check for correct position of the aux.

switches and carry out few close & open

operations. Signals occurred correctly and

driving level is correctly positioned auxiliary

switch.

Working

satisfactory

3. Cable glands Check tightness of the fairleads and locked.

The free fairleads must be covered with

relative plate and blocked.

Secured

4. Terminal

Connectors

Check & clean connector, nuts, bolt, washer

and bimetallic strip. Polish the surface and

freely place bimetallic strip properly, If

provided.

Clean &

apply

conducting

grease

5.

6. Measure & record the Closing and Tripping timing by timer in mili second as per

OEM:

ALIND(BEL VAC bottle) CB Closing < 150

Tripping < 65

BM Closing < 120

Tripping < 80

BHEL BM Closing < 120

Tripping < 80

ABB CB/BM Closing < 65

Tripping < 45

7. Measure the Contact resistance in Micro ohms as per OEM:

ALIND(BEL VAC bottle) < 50

BHEL < 80

ABB < 50



48


Type - 120 SFM – 32 B, Make - CGL

Sl.

No.


Carried Out

Remark


2. Plunger Check & clean free movement of

trip & close plunger.

Free

movement

3. Anti pumping pin Check & clean free movement of

plunger.

Free

movement

4. Shock proof mounting Check for broken. Replace if

broken

Replace

5. Operation timing Check & record closing &

opening timing with timer as per

OEM:

i. Closing

time <

130 ms

ii. Opening

time < 32

ms

6. Contact resistance (CB

close position)

Check & record contact resistance

of fixed & moving contact with

contact resistance meter.

< 50

7. Check & record measurement of dimensions of Circuit Breaker as per OEM:

8. Dimension Measure the following

dimensions.

i. Stroke of moving core of trip

coil

ii Gap between plunger of trip

coil and trip trigger.

iii. Difference between stroke

(ST) and gap (GT).

iv. Stroke of moving core of

closing coil.

v. Gap between Anti pumping

lever and closing trigger.

vi. Difference between stroke

(SC) and gap G.C1).

vii. Gap between anti pumping

lever and anti pumping pin.

viii. Gap between anti pumping

lever and closing trigger

2.8 – 3.2 mm

1.0 -1.4 mm

1.6 – 2.4 mm

4.5-5.5mm

2.0-3.0 mm

2.5-3.5 mm

1.0-2.0 mm

2.3-3.0 mm



49

Sl.

No.


Out

Remark

ix. Stroke of spring operating mechanism.

x. Gap between roller and cam (G).

100 mm ±3 mm

1.4 mm ±3 mm

9. Checking of gas pressure setting:

10. Gas pressure Normal 7.0 kg/cm2

Alarm 6.5 kg/cm2

Lockout 6.0 kg/cm2

3.5.5 25 kV SF- 6 Circuit Breaker (GCB)

Type - 50 SFGP - 20A, Make CGL

Sl.

No.


Carried Out

Remark


2. Connector Check & clean connector, nuts, bolt,

washer and bimetallic strip. Polish the

surface and freely place bimetallic

strip properly, If provided.

Clean

3. Operation

timing

Check & record closing & opening

timing with timer.

i. Closing time < 100 ms

ii. Opening time < 43 ms

4. Closing coil Check & record closing coil parameter

as per OEM:

i Voltage

ii Resistance

iii I R Value

Check with measuring instrument (500

v magger & millimeter)

i. Voltage 110V DC+/- 10%

ii. Resistance 22.28

iii. IR Value 20 M 2 MΩ

5. Trip coil Check & record trip coil parameter as

per OEM

i Voltage

ii Resistance

iii I R Value


(500 V magger & millimeter)



iii. IR Value 2 MΩ

6. Spring

charging

motor

Check & record spring charging motor

parameter as per OEM:

i Voltage

ii I R Value


V magger & millimeter).


ii. I R Value 2 MΩ

7. Contact

resistance (CB

close position)

Check & record contact resistance of

fixed & moving contact with contact

resistance meter.

< 50


Gas Pressure Normal 5.0 kg/cm2

Alarm 4.5 kg/cm2

Lockout 4.0 kg/cm2



50

3.5.6 132/25 kV SF-6 Circuit Breaker

Type - 70 – SFM – 32A, MAKE - CGL

Type -120 – SFM – 32A, MAKE – CGL

Sl.

No.


Carried Out

Remark


2. Surface of

rollers and

sliding

Check & lubricate the bearing surface

of rollers and sliding surfaces of

lever.

Lubricate as per annexure

‘III’

3. Mechanism Check manual operation of

mechanism slowly at 80% of normal

voltage. Ensure that link and lever

should move freely.

Operate at 88% Volt DC

4. Tripping

mechanism

Check the clearance ST (solenoid

magnet stroke) between armature and

core by feeler gauge.

Between armature and core

2.0 to 2.4 mm

Check & record the clearance GT

between plunger and trigger by feeler

gauge.

0.5 to 0.9 mm

Check the clearance & record of ST,

GT

1.5 to 1.7 mm

5. Closing

Mechanism

Check the clearance SC (solenoid

magnet between Armature and core

SC

4.5 to 5.5 mm

Check the pumping prevention pin to

latch distance clearance “p” between

anti pumping Pin and latch

P=1 to 2 mm

6. Pole and Mechanism setting

Check & record mechanism setting of interrupter & operating mechanism:

Operating

Mechanism

Check over stroke “SO” completely

open position to stop position.

6± 1mm (B2 – B1)

Interrupter Measure the stroke and contact wipe

between fix contact and moving

contact of pole

Stroke (A1) – (A3)

=180 + 2 mm, -5 mm

Wipe (A2- A3)

= 36 ±2mm

Operating Mechanism Stroke:- Check

stroke “S” from closed portion to

completing opened position.

Stroke (B3-B2) = 40 + 1

mm – 3 mm

7. DC motor:

i. Inlet

filter

Check & clean inlet filter. Replace, if

damaged.

Replace

ii.Carbon

brushes

Check & clean condition of carbon

brush and commutator. Replace, if

defective carbon brush.

Replace

iii.‘V’ Belt

of motor

Check condition and tension of belt

motor to compressor. Replace the

belt, if defective or loose.

Tension < 2 times of belt

diameter.



51

Sl.

No.


Carried Out

Remark

8.

Operation

timing

Check & record

closing &

opening timing

with timer.

70-SFM-32A i. Closing time < 100 ms

ii.Opening time < 30 ms

120-SFM-32A i. Closing time < 100 ms


9. Contact

resistance

(CB close

position)



resistance meter.

< 50

10. Safety

valves

Check the control valve for air

leakage and safety valve for function.

Working condition

11. Air pressure

charging

time

Check & measure charging of time

for pressure at 0.0 kg/cm2 to 15

kg/cm2

Less than 20 minutes for

70 lit. air reservoir and

record

12. Checking of setting of

70-SFM-32A 120-SFM-32A

Air pressure Alarm 13.2 kg/cm2 13.5 kg/cm

2

Trip 12.0 kg/cm2 13.0 kg/cm

2

Gas

pressure

Normal 5.0 kgf/cm2 6.0 kgf/cm

2

Alarm 4.5 kgf/cm2 5.5 kgf/cm

2

Lockout 4.0 kgf/cm2 5.0 kgf/cm

2


Type -ELF SL- 4 - 1 Double Pole, MAKE – ABB

Sl.

No.


Carried Out

Remark



washer and bimetallic strip. Polish

the surface and freely place

bimetallic strip properly, If provided.

Clean

3. Operation

timing


timing with timer as per OEM.


ii.Opening time < 35 ms

4. Closing coil Check & record closing coil

parameter a per OEM:

i Voltage

ii Resistance

iii I R Value


500 V magger & millimeter)

i. Voltage 110V DC+/-

10%

ii. Resistanc 20.07 Ohm



per OEM :

i Voltage

ii Resistance

iii I R Value


(500 V Magger & millimeter)


10%

ii. Resistance 20.07 Ohm

iii. IR Value 2 MΩ



52

Sl.

No.


Carried Out

Remark

6. a. Compressor

motor

b. Motor

bearing

Check & record compressor motor

parameter:

i. Voltage

ii. Power

iii. I R Value


500 V Magger & millimeter)

Check bearing for free movement,

lubrication. Replace, if bearing jam,

and lubricate.

a.


10%

ii. 2 HP, 16.5 Amp.

iii. IR Value 2 MΩ

b. Replace bearing

7. Checking of setting and record as per OEM

Gas Pressure Normal 7.0 bar

Alarm 6.2 bar

Lockout 6.0 bar

Air Pressure Normal 20.5 bar

Alarm 18.0 bar

Lockout 17.0 bar

8. Contact

resistance (CB

close position)



resistance meter as per OEM

< 51 at 20deg.C

3.5.8 25 kV SF-6 Circuit Breaker/Interrupter

Type - SF-6 EDF SK-1-1 (S), MAKE – ABB

Type - SF-6 EDF SK-1-1, MAKE – ABB

Sl.

No.


Out

Remark




surface and freely place bimetallic strip

properly, If provided.

Clean

3. Operation

timing

Check & record closing & opening timing

with timer as per OEM.



4. Closing coil Check & record closing coil parameter as

per OEM:

i Voltage

ii Power

iii I R Value

Check with measuring instrument (500 V

magger & millimeter)


10%

ii. 500 W

iii. IR Value 2 MΩ



53

Sl.

No.


Out

Remark

5. Spring

charging

motor



i Voltage

ii Power

iii I R Value


V magger & millimeter)


10%

ii. 750 W

iii. IR Value 2 MΩ

6. Contact

resistance

(CB close

position)



resistance meter.

< 42 at 20 deg. C


8.

Gas Pressure

Normal 7.0 bar

Alarm 6.2 bar

Lockout 6.0 bar

3.5.9 25 kV SF- 6, Interrupter (Single, Double Pole)

Type- 30 SFGP – 25 A, MAKE - CGL

Type- 25 SFGP – 25 A, MAKE - CGL

Sl.

No.


Carried Out

Remark


2. Connector Check & clean connector, nuts,

bolt, washer and bimetallic strip.

Polish the surface and freely place

bimetallic strip properly, If

provided.

Apply electrical joint

compound as per annexure

‘IV’

3. Operation

timing

Check & record closing & opening timing with timer.

30 SFGP – 25 A i. Closing time < 100ms


25 SFGP – 25 A i. Closing time < 100ms


4. Closing coil Check & record closing coil


i. Voltage

ii. Resistance

iii. I R Value


(500 v magger & millimeter)


10%


iii. IR Value 20 M 2 MΩ

5. Trip coil Check & record trip coil


i. Voltage

ii Resistance

iii I R Value


(500 V magger & millimeter)


10%


iii. IR Value 2 MΩ



54

Sl.

No.


Carried Out

Remark

6. Spring

charging

motor

Check & record spring charging

motor parameter as per OEM:

i. Voltage

ii. Current

iii. I R Value


(500 V magger & millimeter).

i. Voltage 110V

DC+/- 10%

ii. 5.2A


7. Contact

resistance

(CB close

position)



resistance meter.

< 50


Gas Pressure

Normal 5.0 kg/cm2

Alarm 4.5 kg/cm2

Lockout 4.0 kg/cm2



Sl.

No.


Out

Remark






Clean

3. Mechanism Check manual operation of mechanism

slowly at 80% of normal voltage. Ensure

that link and lever should move freely.

Operate at 88% Volt DC

4. Operation

timing


timing with timer.



5. Closing coil Check & record closing coil parameter

as per OEM:

i Voltage

ii Resistance

iii I R Value

Check with measuring instrument( 500


i. Voltage 110V DC + /-

10%

ii. Resistance 15

iii. IR Value 2 MΩ


per OEM:

i Voltage

ii Resistance

iii I R Value




10%

ii. Resistance 15

iii. IR Value 2 MΩ

7. Spring

charging

motor

Drain oil from gear box of the spring

charging motor and refill the oil up to

the mark.

Replace the oil



55

Sl.

No.


Out

Remark

8. Contact

resistance (CB

close position)



resistance meter.

< 50

9. Linear stroke Measure & record the linear stroke of:

Closing spring

Tripping spring

-Closing spring 108 mm

-Tripping spring138 mm

10. Contact rod Measure & record the travel of moving

contract rod.

275 + 2.5 mm

11. Fuses Check & replace defective fuses. Replace



Sl.

No.


Out

Remark






Clean

3. Operation

timing

Check & record closing & opening timing

with timer as per OEM.



4. Closing coil Check & record closing coil parameter as

per OEM:

i Voltage

ii Watt

iii I R Value




10%

ii. 500 W

iii. IR Value 2 MΩ

5. Trip coil Check & record trip coil parameter as per

OEM :

i Voltage

ii Watt

iii I R Value




10%

ii. 500 W

iii. IR Value 2 MΩ

6. Spring

charging

motor



i. Voltage

ii. Watt

iii. I R Value




10%

ii. 735 W

iii. IR Value 2 MΩ

7. Contact

resistance

(CB close

position)

Check & record contact resistance of fixed

& moving contact with contact resistance

meter.

< 42 at 20 deg. C


9.

Gas Pressure

Normal 7.0 bar

Alarm 6.2 bar

Lockout 6.0 bar



56

3.5.12 Auxiliary Transformer Type - Double wound, single phase, oil immersed natural air cooled and step down


Sl.

No.


Out

Remark

1. Carry out following work in addition to monthly, quarterly & half yearly

schedule

2. Winding

continuity

Measure & Record winding continuity

on all tapings with multimeter/500 V

megger.

Zero

3. Tap changer Check the smooth operation of tap

changer on all tapings.

No obstruction during

operation

4. Acidity of oil Check the acidity of transformer oil. Maximum 0.5 mg

KOH/gm

5. Ratio test Conduct ratio test by applying AC

supply to HV winding and measure the

voltage at LV side winding.

Record & compare

with previous reading

6. Jumpers Check HT and LT jumpers & lugs for

loose & flash mark. Replace if loose &

flash.

Replace

7. Painting Paint to be done, if color of tank is

faded/ rusted.

Painted with epoxy

and polyurethane

paints as per A & C

slip no. 8 to the RDSO

specification

no.ETI/PSI/118

(10/93)

8. DO fuse wire Replace the fuse wire with new one. Replace


Sr. Item Inspection And Work To Be Carried

Out

Remark

1. Carry out following work in addition to quarterly & half yearly schedule

2. Duplicate

earthing

Check duplicate earth conditions for

broken & loose. Attend the same.

3. Oil testing if

possible

Test the oil with BDV tester. If possible. Permissible limit

4. Ratio test Conduct ratio test by applying AC

supply to HV winding and measure the

voltage at LV side winding.

Record & compare

with previous reading

5. Painting Paint to be done, if color of tank is

faded/ rusted.

painted with epoxy and

polyurethane paints as

per A & C slip no. 8 to

the RDSO specification

no.ETI/PSI/118 (10/93)



57

3.5.14 Current Transformer 220 kV/132 kV/25kV


Sl.

No.


Carried Out

Remark


2. Arching horn

gap If provided

Check & measure arching horn gap

as required.

Record

3. Oil testing, if

possible

Test the oil with BDV tester. BDV more than 40 kV

4. Painting Check for painting, if color of tank is

faded/ rusted.





no.ETI/PSI/118 (10/93)

5. Polarity test Conduct polarity test and check the

direction of current.

Reverse

6. Ratio test Conduct ratio test by applying

current to HV winding and measure

the current LV side winding.

Record & compare with

previous reading

3.5.15 220/132/ kV Isolator


Sl.

No.


1. Carry out following work in addition to monthly & half yearly schedule:

2. Operation of

isolator( Double

& Triple pole)

Check the operation of isolator slowly and

check for simultaneous operation of blades on

the poles and correct alignment of blade tips

in the fixed contact jaws of the poles.

Correct

alignment

3. Insulation

resistance

Measure & record IR values of pedestal and

tie rod insulators with 2.5 kV megger.

More than

1000 M

4. Operating handle

of main blade

and earth blade,

if provided

Check the locking arrangement to the

operating handle of main blades and earth

blade.

Working

satisfactory

5. Bearing Check & clean the bearings of rotating

bushings of insulator and lubricate with

grease.

Lubricate

with grease

6. Bus connections

and bimetallic

strips

Check & clean for tightness, sign of

oxidation on bus connections and bimetallic

strips correct if necessary. Replace

bimetallic, if required

Replace

7. Paint Check & replace rusted parts and paint the on

rusted parts, if any

Cold

galvanizing

paint



58


Type – Single pole, Double pole, and Bipolar

3.5.17 Motorised Isolator, 25 kV


Sl.

No.


1. Carry out following work in addition to quarterly & half yearly schedule:

2. Insulation

resistance of

motor

Measure & record insulation resistance of

winding with 500V megger

More than 2

M

3. Commutator Check & clean commutator with dry cotton

cloth.

Clean

4. Carbon brushes Check carbon brushes for under size. Replace

if necessary

Replace

5. Arching horn, if

provided

Check correct setting and alignment of arcing

horn. Adjust if required

Correct

alignment

Sl.

No.

Item Inspection And Work To Be Carried Out Standard

Value

Carry out following work in addition to monthly & half yearly schedule:

Operation of

isolator( Double

pole)

Check the operation of isolator slowly and

check for simultaneous operation of blades on

the poles and correct alignment of blade tips

in the fixed contact jaws of the poles.

Correct

alignment

Interlocking

operation

Check & clean interlocking operation with

circuit breaker.

Working

satisfactory

Blade tips and

fixed contact

fingers

Check the condition of the blade tips and fixed

contact fingers for any sign of over heating

and presents of buffs. Clean the buffs.

Clearances of

blade

Measure the clearances of blade in open

position. Measure and record and adjust if

necessary.

Minimum

500 mm

Insulation

resistance

Measure & record IR values of pedestal and

tie rod insulators with 2.5 kV megger.

More than

1000 M

Bus connections

and bimetallic

strips

Check & clean for tightness, sign of

oxidation on bus connections and bimetallic

strips correct if necessary. Replace

bimetallic, if required

Replace

Paint Check & replace rusted parts and paint the on

rusted parts, if any

Cold

galvanizing

paint



59

3.5.18 198/120/42 kV Surge Arrester Ref: TI/MI 0041 REV - 0

Sl.

No.


Out

Remark

1. Carry out following work in addition to monthly, quarterly & half yearly schedule:

2. Lightning arrestor

(LV side) HT-E

Check, measure & record insulation

resistance of each unit of lightning arrestor

with by 2.5/5.0 kV megger.

IR value more

than 1000 M

ohms


(HV side) )HT-E

Check, measure & record insulation

resistance of each unit of lightning arrestor

with by 2.5/5.0 kV megger.

IR value more

than 10,000 M

ohms

4. Earth resistance Check & record the earth resistance of

each earth connection with earth resistance

meter.

Not more than 0.5

ohms


details

Check & record the following:

i. location

ii. rating

iii. make

iv. Sr no

v. date of Mfg

vi. date of commission

vii. date of measurement

viii. IR value

ix. THRC value of leakage current,

x. No of surges passed

Measure and record

Record

6. THRC leakage

current value

Check & record leakage current before

and after cleaning of LA with THRC

meter.

If the leakage

current between

350 – 500 μA,

keep it under

close observation

& beyond 500

μA, remove from

service

3.5.19 Capacitor Bank (TI/MI/00026 Rev. 2)

Sl.

No


1. Carry out following work in addition to quarterly & half yearly schedule:

2. Tan Delta

(Dielectric

loss angle)

Measure & record the ten delta of the

capacitor units with the help of a standard

shearing bridge.

Dielectric loss

angle not more

than 0.0005

3. Capacitance

value of

capacitor

Measure & record the readings of the

capacitance upto the first decimal value by

digital multimeter. Changes in values beyond

6% indicate that the capacitor bank is likely to

fail.

Replace the

capacitor if

value beyond

6%

4. Protective

relays

Check record of functioning of protective

relays and setting.

Working

satisfactory



60

Sl.

No


Out

Remark

5. NCT setting Check & record the NCT relay

setting and change in the NCT relay

settings are required to be examine.

as per RDSO

guidelines

6. Fasteners and

the connectors

Check proper tightening of the fasteners

and the connectors. Tighten, if loose.

Tighten

7. Temperature of

capacitor

Check & record the temperature rise in

24 hrs of the capacitor unit with by

suitable thermometer on the can of the

capacitor bank.

The temperature

should not raise 15

deg. above the

ambient temperature


Sl.

No.


Carried Out

Remark


2. Oil

condition

Check the condition such as less

BDV, oil color, and sludge in oil.

Centrifuge the oil, if necessary.

Centrifuge

3. Painting

Paint to be done, if color of tank is

faded/ rusted.





no.ETI/PSI/118 (10/93)

3.5.21 Series Reactor (Dry Type)

Sr. Item Inspection And Work To Be

Carried Out

Remark

1. Carry out following work in addition to monthly and half yearly schedule

2. Insulation

resistance of

winding

Check insulation resistance &

record:

Winding to earth (ambient temp

also to be recorded) with 2.5 kV

megger.

Minimum 200 M ohms

3. Painting

Paint to be done, if color of body

is faded.


polyurethane paints as per

A & C slip no. 8 to the

RDSO specification

no.ETI/PSI/118 (10/93)

4. Earthing

connections

Check & tighten earthing

connections. Replace the rusty or

overheated bolts and nuts if

necessary.

Replace

5. Terminal

Connector &

Bus-bar

connectors

Check & tighten of bolts and

nuts of top & bottom. Replace

the rusty or overheated bolts and

nuts if necessary.

Replace

6. Coil Check coil for warm and find out

the reason and attend it.

Attend



61


Sr. Item Inspection And Work To Be Carried Out Remark

1. Carry out following work in addition to monthly and half

yearly schedule

2. Operation of

relay

Check & record operation of all relays.

Working

satisfactory

3. Testing of

relay

Conduct relay testing by testing instrument

and record.

Compare as

per setting

4. Contactors,

push button,

switches

Check & clean all contactors, push button

and switches for burnt, carbonize or corroded

marks. Replace if defective.

Replace

5. Check voltage Check & record voltage between + (ve) to

Earth & - (ve) to Earth. If observe more

differ and take action.

Check circuit

3.5.23 Condition Based Maintenance through Thermo vision Camera (Traction Substation)

1. AC TRD (Traction Sub-station, SP and SSP)

Sl. No. Item Inspection And Work To Be Carried Out Standard Value

1. Carry out all work in half yearly schedule

3.5.24 Earthing & Bonding


1. Carry out all work in half yearly schedule

2. Buried

rail

Check condition of connections rail to buried rail and

mat to buried rail. Clean & tighten all connections

Intact

connection



1. Carry out following work in addition to monthly , quarterly and half yearly

schedule

2. Transformer

winding

Measure & record the insulation resistance of

winding at room temperature with 500 V

megger.

More than 2 M

3. Electrolyte

condenser

Measure & record the capacitance value with

LCR meter. Replace if open circuited/ short

circuited.

Replace

4. Cable

glands

Check cable holes and unwanted holes. Provide

proper size of glands, close unwanted holes and

gaps.

Cork gasket and

HOLDITE

compound

5. Cable ends Check for crimping of cable ends with

connectors/lugs and cable ends crimped with

suitable size of connectors/lugs.

Proper crimped



62

3.5.26 AC/DC Distribution Panel

S. No. Item Inspection And Work To Be

Carried Out

Remark

1. Carry out following work in addition quarterly and half yearly schedule

2. Cable

glands

Check cable holes and unwanted holes.

Provide proper size of glands, close

unwanted holes and gaps.

Cork gasket and HOLDITE

compound

3. Cable

ends

Check for crimping of cable ends with

connectors/lugs and cable ends crimped

with suitable size of connectors/lugs.

Proper crimped

4. Insulation

resistance

of cable


resistance of cable at room

temperature with 500 V megger.

More than 2 M

5. Stickers/

paint

Check stickers/ paint to MCBs/rotary

switch. Paste new sticker/paint to

MCBs/rotary switch, if faded.

Replace

6. Painting Paint to be done, if color of panel is

faded/ rusted.


polyurethane paints as per A

& C slip no. 8 to the RDSO

specification no.ETI/PSI/118

(10/93)

3.6 THREE YEARLY SCHEDULE 3.6.1 SF-6 Circuit Breaker & Interrupter for M/s. ABB & CGL

Sl.

No.


1. Carry out following work in addition to monthly, half yearly & yearly schedule

2. Mechanical

travels

Measurement & record of mechanical

travels. Adjust if required.

As per

maintenance

manual

3. Door gasket &

hinges

Replace & check the door gasket of the

operating mechanism and hinges for

damages. Replace with new one.

Replace

4. Movement of

rollers

Check the free movement of rollers. If not

free, replace the same.

Replace

5. Contact

resistance

Measure the value of contact resistance of

pole between upper terminal and lower

terminal. If value is more than 120% of the

design value specified in maintenance

manual contact manufacturer.

Approach the

manufacturer for

rectification

3.6.2 220 kV/132 kV/25kV Current Transformer


1. Primary

injection

test

Conduct primary injection test and record

the reading.

Compare with pre-

commissioning

rest



63

3.7 AFTER 5 YEARS OR WHEN NEED

3.7.1 Power Transformer

Sn. Item Inspection And Work To Be Carried

Out

Remark

1. Carry out following work in addition to monthly, half yearly & yearly schedule

2. Painting of

transformer

tank,

conservator

radiator and

other exposed

parts

Clean the exposed parts thoroughly.

Transformer tank and other parts should

be painted with epoxy and polyurethane

paints as per A & C slip no. 8 to the

RDSO specification no.ETI/PSI/118

(10/93)

- In case of previous

enamel paints, the

repainting may be

carried out after 3

years polluted area.

- In case of previous

epoxy and

polyurethane paints

the repair painting

may be carried out

after 5 years.

3. Pipe work Check for any damages, misalignment

and leakages. If any misalignment the

pipe should be realigned and joint

made.

--

4. Test oil in

transformer

Measure the inhibitor content in the oil.

In the new oil it has to be within 0.25 –

0.30% by total weight of oil.

If the inhibitor content in the oil reduces

to 0.15% it should be re-inhibited by

adding required amount of DBPC (2,6

Ditertiary Bytyl para Cresol)

5. Magnetizing

current test

with

voltmeter,

ammeter and

lamp.

Check by applying 230 V AC supply

preferably on LV side with series lamp.

Compare the value with respect to pre

commissioning value. Any abnormal

increase to the order of 50 times

indicates that these are a fault inside.

Ensure that the

comparison is done to

the value taken at LV

side only.

6. Winding

resistance test

with wheat

stone bridge,

voltmeter and

ammeter.

The test conducted on principal tap by

applying DC current. The measured

value should be converted to 75°C.

Compare the value with the pre-

commissioning/ factory test values.

Deviation in absolute value shall be less

than ± 5% of pre-commissioning or

factory test value.

This test should be last

the test on winding to

avoid DC flux remaining

in core resulting

erroneous value in the

other test.

7. Impedance

test with

voltmeter and

ammeter.

Test to be conducted on principal tap

applying 230V single-phase AC to the

HV side with LV side shorted and

calculate V/I and convert to percentage

impedance.

Compare the value with respect to pre-

commissioning value, any deviation

beyond 5% calls for further analysis.

Any deviation beyond

2% from the earlier

values shall be

considered for keeping

watch on the

transformer.



64

3.7.2 Vacuum Circuit Breaker & Interrupter

The operating mechanism should be Checked/attended (without dismantling the

circuit breaker/interrupter) if circuit breaker has completed 5 years of service or 10,000

electrical switching operations.

3.8 SIX YEARLY SCHEDULE 3.8.1 SF-6 Circuit Breaker & Interrupter, Make-ABB & CGL

The following items should be checked/attended (without dismantling the circuit

breaker/interrupter) if circuit breaker has completed 6 years of service or 2000 electrical

switching operations or 5000 mechanical CO operations.

In case of interrupter, if it has completed 6 years of service or 5000 Electrical/

Mechanical CO operations.

Sl.

No.


Out

Remark

1. Carry out following work in addition to monthly, half yearly, yearly, three yearly

schedule

2. Inspection and

re-adjustment of

Operating

mechanism

Measurement of mechanism dimension,

Lubricating the mechanism, Leakage

check of dash pot oil, Looseness of

circlips and nuts, Check free movement of

antipumping pin and trip & closing

plungers, Replacement of some parts of

mechanism.

3. Connecting rod

end joint and

Bellows

Check the crack of connecting rod end

joint and bellows. Replace, if crack

Replace

4. Lubricate the

mechanism

linkages

Check & clean lubricating mechanism

linkage with dry cotton cloth.

As per annexure

5. Contacts and

nozzle of

interrupting pole

Check contacts and nozzle. Renew them,

if required.

As per

maintenance

manual

6. Absorbent Check absorbent for SF6 gas by-products.

Renew the absorbent for SF6 gas by-

products

Renew

7. Moisture sealant Check moisture sealant to all cemented

joints of porcelain. Apply moisture

sealant to all cemented joints of porcelain.

Apply moisture

sealant

8. Shock absorber Replace shock absorber Replace

9. Gas system Check setting of gas density switch. As per maintenance

manual

10. Compressor Take out the compressor after every six

year refit the items which are damaged

Replace the

defective items



65

3.9 PERIODIC OVERHAULING

3.9.1 Power Transformer (TI/MI/00039 Rev 1)

Overhauling of a transformer is normally undertaken either if it is faulty (internal) or

at the end of 10 - 12 years of its service by way of periodic maintenance. It is necessary to

review and analyze the periodical DGA values to check any abnormal variation and

healthiness of the transformer. The procedure for periodic overhauling of transformer dealt

herewith is applicable for bell type tank construction transformers. Periodical overhauling

(POH) of transformer can be done either at site (TSS) or in traction repair shop or through

trade. The transformer should not be opened during rainy /cloudy weather for

inspection/repair/overhaul.

Tests Prior To Undertaking POH

Following tests should be conducted on traction transformer before

undertaking POH.

a) Measure dielectric strength (BDV), acidity, water content (ppm) & tan delta of

transformer oil.

b) Dissolved gas analysis (DGA) of transformer oil.

c) Measurement of winding resistance on all taps.

d) Measure the insulation resistance of winding and polarization index.

e) Measurement of tan delta and capacitance of condenser bushing.

Insulation resistance & polarization index of the windings and BDV, acidity

& DGA of transformer oil and the values of various tests shall be recorded. The

same shall be compared with the values recorded after the completion of

overhauling.

Steps For Overhauling

Untanking of Transformer

Commencing the work, drain out the oil, disconnect all leads and remove

manhole covers, accessories, conservator, breather, radiator, fittings, HV, LV

bushings and store them in a safe place. One set of gaskets of standard quality shall

be available for replacement during POH as per annexure IX. The bell tank shall be

removed by suitable crane/winch carefully so that the bell tank does not damage the

active parts during dismantling. Defects observed during inspection/ test schedule for

the subject transformer shall be recorded and taken into account and defects like

leakage in tank, conservators and radiators etc. shall be attended and rectified

permanently during POH of transformer.

Items To Be Checked / Attended

Following items are required to be checked/ attended during overhauling

Insulating oil of the transformer main tank

Transformer windings & internal parts of transformer and tank.

Conservator, radiators and other metal parts including associated pipes.

Check the drain valve, oil-sampling valve, filter valves etc.



66

Check insulation blocks, permali wood packing, spacers, wedge and keyed

blocks and insulating rings with securing arrangement in the winding for their

displacement due to frequent & repeated short circuit during service.

Check the pressure screws with belleville washers and pressure cup for its

intactness along with permali wood packing.

Check the top and bottom yoke bolts and check ferrule insulation tube and

dielectric strength by 2kV ac for 1 minute.

Check electrical joints, earth connections, between core to core & tank, lead

connections for tap changer and transformer for tightness and intactness.

Check clearances of the active part form the tank body.

The contacts of off-circuit tap changer.

Check the operation of off- circuit tap changer.

Check the tightness of all fasteners, core bolts and core with tank fasteners etc.

Check the condenser bushing for correct oil level, crack and leakage, if any.

Transformer tank, conservator, radiators, pipe work and other associated parts.

Checking of control cables for its condition.

Tanking of Transformer

Finally put back the bell tank, assemble the bushings, check tightness of all

internal connections, and provide new gaskets. The insulating oil has to be

checked/tested as per IS: 1866-2000 and its replacement has to be done on its

condition basis.

Drying-Out/Filtration of Transformer

Vacuum drying of the transformer is to be done generally as per IS 1866:

2000 and by maintaining the pressure less than 0.10 torr and maximum temperature

of 600 C. During filtration/drying out process, the reading of temperatures and IR

value shall be recorded every two hours form commencement till full operation is

completed. The filtration/ drying out shall be done as per para 20208/20210 of

ACTM - Vol. II, Part I

To ensure that the moisture has been removed from the transformer, the PI

value after drying has to be measured and it should preferably be achieved equal to

or more than 2. The following table is to be used as guideline reference for the PI

value of the windings.

Item to be

inspected/tested

Inspection/Testing Action required / acceptance norms

IR of winding and

Polarization Index

(PI) with 5kV megger

for:

HV-LV,

HV-LV,E,

LV-HV,E

Insulation resistance

to be measured for

10 sec, 60 sec and

600 sec. Calculate PI

as R60/R10 and as

R600/R60.

Compare with values at the time of

commissioning/ last recorded.

PI Insulation condition.

< 1.0 Dangerous

1.0 – 1.1 Poor

1.1 – 1.25 Questionable

1.25 – 2.0 Satisfactory

> 2.0 Good



67

Precautions

The tools like spanners and foreign objects like washers, pieces of cloth, etc.

are sometimes inadvertently left behind in the transformer which present hazard of

short circuits. It is, therefore, important that the tools, etc. used during overhauling

shall be listed out at the beginning and accounted for at the end of the work.

Checks / Tests After Overhauling

After completion of overhauling of transformer test/ checks shall be done:-

i) Voltage ratio test with Voltmeter, Ammeter and Lamp or with ratio meter.

ii) Winding resistance test with Whetstone bridge or voltmeter, ammeter method.

iii) Magnetizing current test with voltmeter, ammeter and lamp.

iv) IR of windings and polarization Index with motorised 5 kV Megger.

v) Tests on transformer oil for BDV, ppm, tan delta and acidity.

vi) Checking of protection equipment for their working i.e. buchholz, PRD,

MOLG, WTI and OTI.

vii) All gasket joints for any leakage.

viii) Check relay and alarm contacts for their operation.

ix) Check control boxes, terminal boxes etc. for water tightness against ingress of

moisture and if required replace gasket.

x) Check dial type OTI and WTI for freedom of pointer.

xi) Check the IR value and the secondary winding resistance of bushing CTs.

xii) Bushing: tan delta and capacitance test should be conducted to ensure its

health and tallied with its prior test values. Max. allowable Tan Delta and

capacitance is 0.007 and 110% of the factory set value respectively.

xiii) TC is to be checked for its proper /required operation such as

(a) Manual

(b) Local operation (electrical)

(c) Remote electrical operation

xiv) (a) Check oil level in transformer tank, conservator, condenser bushing, and

TC etc.

(b) Check OTI and WTI pockets and breather oil cup and replenish the oil if

required.

(c) Arcing horn gap as per drawing

xv) Check that all earthing connections of various parts/points are made properly

as per diagram plate.

xvi) Check wherever provided, air delivery cooler fan are sufficient and working

in right direction.

xvii) Ensure silica-gel in breather active and blue and oil is upto correct level in the

cup.



68

xviii) Check the thermometer oil pockets on tank top and header etc. filled properly.

xix) Remove/clear all the tools and other associated equipments used in the POH

from transformer.

xx) Lock the roller to prevent the movement on rail.

xxi) Release the trapped air through air release plugs and valves.

Commissioning of Transformer

The Commissioning of traction transformer after POH shall be done as per

para20905/20906/20907 of ACTM - Vol. II, Part I

CONCLUSION

Performance of transformer after POH shall be evaluated by comparing the

result of insulation resistance & polarization index of windings and BDV, water

content (ppm), tan delta, acidity & DGA of transformer oil. All these values shall be

kept in records for monitoring the performance in service.

ITEMS REQUIRING REPLACEMENT WITHOUT FAIL DURING PERIODIC

OVERHAUL OF TRACTION POWER TRANSFORMER.

1. Insulating oil

2. Gasket and rubber items as per annexure IX

3. Pre compressed board used to insulate bottom of tank with active parts.

4. Silica gel

Items Requiring Replacement During POH On Condition Based

Insulation Material

Permali wood packing in coil clamping and locking box welded to tank and core packing

etc..

Coil clamping screws and plate Belleville washer, permali wood packing used in with

hydraulic jacks for clamping coil at required pressure.

Radial paper covered insulation over leads from windings to tap changer.

Radial paper covered insulation over leads to bushing with clamping arrangement

permali wood / PCP board.

Radial paper covered insulation between winding sections of both legs.

Fiber glass ferrule and insulating core/yoke bolts with permali washers and PCP board

(used to insulate yoke with core stud)

Items used in Winding

Locking spacers and plain spacers.

Keyed blocks for tapping windings.

Keyed blocks for HV and LV winding.

Core packing of PCB /Perma wood.

Top/bottom common washers of PCB.

Top /bottom clamping ring of PCB etc.



69

Other Items

Cable clamps /securing arrangement

Cable glands, cable lugs, nut bolts and LED/Bulbs etc.

Relays/ switches, push buttons, capillary tubes with bulbs etc.

Items /parts relating tap changer (OCTC)

Bakelite phase board and selector ring

Brass slip rings and brass fixed contacts,

Copper brush assembly and electrolytic copper moving contacts,

Gears and bearing in driving mechanism,

Paper covered copper connection cable with socket (between fixed contact and terminal

stud),

Flexible braid of electrolytic copper to connect moving contact and copper brush.

Spring in moving contact holder for contact pressure



70

3.9.2 AUXILIARY TRANSFORMER

Overhauling of a transformer is normally undertaken either if it is faulty or at the end

of 7 to 10 years of service. Overhauling (POH) of transformer can be done either in repair

shop or through trade. Following steps shall be followed for POH overhauling.

General cleaning

First of all remove as much dirt as possible particularly around the transformer

tank, radiator, conservator, HV & LV bushing, neutral link block covers etc. Blow the

dust of transformer & radiator with compressed air.

Activities to be done during POH

The items which are required to be checked/ attended during overhauling are given

below:

a. Record brief history of the equipment.

b. Visual Inspection:

Check the complete tank for any deformation and crack.

Check HV & LV bushing for any cracks/chipped discs.

Check condition of silica gel container and silica gel.

Check the oil leakage from auxiliary transformer tank, oil pipes, flange joints,

conservator, drain plugs and vent plugs.

Check the thread condition of filter inlet and out let valves, drain plug and

breather socket.

Check condition of all gaskets/washers.

Check conservator tank, oil level indicator glass.

Check condition of arcing horn.

Note all the defects and deficiencies.

Before opening of equipment

The following test to be carried out on transformer before opening of transformer.

a. Insulation resistance

Check the insulation resistance of windings between.

a. H V winding to earth by 2.5 kV megger.

b. L V winding to earth by 500V megger.

c. H V winding to L V winding by 2.5 kV megger.

b. Continuity Test

Check the continuity of the following windings with the help of multimeter.

Primary winding

Secondary windings

c. Tap changer

Check the condition and operation of tap changer at all tap positions.

d. BDV of transformer oil

Measure the BDV of transformer oil by automatic break down voltage kit.



71

e. Polarization ratio

The test consists of applying dc high voltage 2500V, with the help of a

megger, continuously between winding and earth, and noting the insulation

resistance at the end of 10sec, 60sec.

f. DGA of transformer oil

Dissolved gas analysis (DGA) of the oil of a transformer is a very useful

technique to assess the internal condition of the transformer.

g. Test on transformer oil

Measure the specific resistance (resistivity), water contents, dielectric

dissipation factor (Tan delta), flash point, neutralization value, sludge etc of

transformer oil.

h. Ratio test

Conduct ratio test of auxiliary transformer.

i . Before carrying out the work, the following works to be carried out.

Drain out the transformer oil from tank.

Disconnect all leads and remove tank top cover, accessories, conservator,

fitting etc.

Disconnect HV & LV bushings and store them in a safe place.

Disconnect the earth leads from the transformer primary earth bushing

terminal link block.

Disconnect all the power cable connection from secondary winding side

bushing.

After opening the transformer

a. Measure Insulation Resistance of winding.

b. Check all core support bolts for any cracks and replace them if required.

c. Check condition of core, winding and lamination.

d. Check for accumulation of water content/ sludge inside the tank.

e. Check earth connections.

f. Check condition of soldered joints.

g. Check the insulation paper for any damage and reinsulated if necessary.

h. Check the condition of tap changer contact tips at all tap positions.

Details of Work to be Carried Out

a. Clean winding and core with new filtered oil.

b. Tighten core bolts and other fasteners to secure the core and winding

properly and replace by new one if worn out.

c. Bake the winding and core by keeping in oven at a temperature of 60 °C.

d. Observe daily improvement in IR values of winding.

e. Clean the tank thoroughly from inside and outside.

f. Check visually inside of tank for any flash mark, hit mark, damage etc.

g. Do the varnishing of the tank inside area with copal varnish.

h. Paint the tank from out side with battleship gray paint.



72

i. Check the oil drain cocks and change washers by a new one, tight and lock them.

j. Check the secondary terminal blocks fixing studs for tightness and they should be oil

leak proof.

k. Check the HV bushing fitting surface, it should be clean and plain.

l. Check the inlet and outlet valves for their proper working and check for oil leakage.

m. Replace all gaskets, oil seal, ‘O’ ring or other rubber/ neoprene items.

n. Tighten earth connection of the equipment.

o. Replace worn out contacts of tap changer.

p. Replace oil level indication glass, if required.

Inspection of Fittings

a. Silica Gel Breather

Check the silica gel breather visually for any abnormality/ damage.

Reactivate silica gel by heating in a shallow pan at a temperature of 150 °C to

200 °C for two or three hours until the crystals should have regained their

original blue tint.

Clean and dry all parts of the breather before filling the container with silica

gel.

Fill the fresh or reactivated silica gel crystals.

Verify that the oil level in the oil cup is correct after reassembly.

b. Radiator

Clean the radiator tubes thoroughly by compressed air and high pressure water

jet if applicable.

Check radiator tubes and fins for any damage if applicable.

c. Conservator

Clean conservator and glass indicator thoroughly.

Check the conservator for any damage, intactness of indicator glass and

condition of glass.

Reassemble after Drying Out the Winding

a Replace all gaskets with new one as per annexure IX before assemble the equipment.

b. Fill the new filtered oil with 60 kV BDV in the tank.

c. Assemble the equipment and connect all winding connections of HV, LV bushings,

tap changer and HV earthing connection.

d. Check, clean and re-fit all accessories of the transformer.

Testing of Aux. Transformer after Assembling

Carry out the following tests on the auxiliary transformer after assembling of

winding and core in tank.

Insulation resistance

Continuity test.

Ratio test.

Voltage out put at different taps.

Magnetising current.



73

Final Checking

Check visually for any oil leakage from any point, coupling, joints etc.

Check any unusual sound of equipment.

Check and ensure oil level in conservator, it should be maximum mark.

Release air from top screw of HV bushing.

Measure final IR values and compare with previous recorded values.

Measure BDV of oil and moisture content (ppm).

Check arcing horn gap.

3.9.3 Vacuum (Circuit Breaker & Interrupter)

Complete overhauling of the circuit breaker/ interrupter operating mechanism and

magnetic actuator shall be done after 20,000 operations or 10 years, whichever is earlier.


Overhauling of a battery charger is normally undertaken either if it is faulty or at the

end of 10 years of its service by way of periodic maintenance. The following parts shall be

replaced during POH.

1. Replace the MCB.

2. Replace the electrolyte condenser.

3. Replace the any defective parts

4. Paint the charger



74

3.10 PRE MANSOON AND PRE WINTER PRECAUTIONS

Before onset of monsoon and winter season, it should be ensure that no maintenance

schedule is overdue for equipment. In the schedule inspection just preceding the monsoon,

special attention should be paid to the vulnerable points likely to permit ingress of moisture

resulting in reduction in dielectric strength of the equipment and rusting of parts.

Sl. No. Item to be check Action taken Remark, if any

1.0 POWER TRANSFORMER

1.1 BDV of oil

1.2 Leakage/Seepage

1.3 Worm Proofing

1.4 Arching horn gap

1.5 IR value

1.6 Silica gel

2.0 CLS AT

2.1 Arching horn gap

2.2 BDV of oil

2.3 IR value

2.4 Leakage/Seepage

2.5 Silica gel

2.6 Oil level

2.7 Checking of un authorized connection from AT

3.0 OIL CB/BM

3.1 BDV of oil

3.2 Leakage/Seepage

3.3 Oil level

3.4 Silica gel

4.0 GAS CB/BM

4.1 Checking of gas pressure

4.2 Checking of air pressure

5.0 CT/PT

5.1 Leakage/Seepage

5.3 IR value



75

4.0 SCHEDULE ACTION PLAN

Sl.

No.

Name of Equipment Schedule to be followed

F/ly M/ly Q/ly H/ly y/ly 3y/ly (ABB/CGL)

5y/ly POH

6y/ly (ABB/CGL)

POH

(10 yly)

1. Batteries & Battery

Charger

2. Battery Charger

3. General Works of TSS,

SSP & SP

4. Power Transformer

5. 25 kV Vacuum Circuit

Breaker / Interrupter

6. 132 kV SF-6 Circuit

Breaker 120 SFM-32B

7. 25 kV SF-6 Circuit

Breaker 50 SFGP-20A

8. 132/25 kV SF- 6

Circuit Breaker 70

SFM- 32A & 120-

SFM-32A

9. 220 kV SF- 6 Circuit

Breaker (ELF SL- 4-1

Double Pole)

10. 25 kV SF-6, D/P

Circuit

breaker/Interrupter

EDF SK-1-1(S) &

EDF-SK-1-1

11. 25 kV SF-6, Interrupter

30 SFGP – 25 A & 25

SFGP – 25A

12. 25 kV Minimum Oil

Interrupter

(HPGE7/9A)

13. 25 kV Single pole SF6

Circuit breaker LTB

72.5 D1

14. Auxiliary Transformer

15. Current Transformer,

220 /132/25 kV



76

16. 25kV Potential

Transformer

17. 220/132 kV Isolator

18. 25 kV Isolator

19. 25 kV Motorised

Isolator

20. Surge Arrester

21. Series Reactor (Oil Type)

22. Series Reactor (Dry Type)

23. Capacitor Bank

24. Control and Relay Panel

25. AC/DC Distribution Panel

26. Battery Charger

27. Condition Based

Maintenance Through

thermo vision camera

AC TRD (Traction Sub

– station)

28. Earthing & Bonding

29. Buried rail

5.0 FORMATS FOR SUBMITTING FAILURES TO RDSO

Railway……….

Division ……….

Depot…..

Ref: TIF-0011 Rev. ‘0’ (Period - October to September)

Submitted to RDSO Annually – 1st November.

PART-I - PROTECTIVE RELAY DATA

TSS FEED

ER CB

No.

CT

Ratio

Transformer

rating (MVA)

Feeder CB Relay operating time (ms)

Type Opening

time (ms)

DPR

(ms)

WPC

(ms)

Inst. OCR

(ms)

Auto recloser

(sec)

Delta-I Panto

flashover

MTR

(ms)

Railway……….

Division ……….

Depot…..

Ref: TIF-0011 Rev. ‘0’ (Period - April to September & October to March)

Submitted to RDSO Half Yearly – 1st May &1

st Nov.

PART-II - TRIPPING DATA RELAY WISE

TSS Feeder

CB No.

Tripping

Target

Tripping in

six month

Auto recloser Action Relay Tripped in This Six Month Period

Trip & Close Lock out DPR WPC Inst./O/C Delta- I Panto Flashover

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

77

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

July, 2

01

4

Railway……….

Division ……….

Depot…..

Ref: TIF-0011 Rev. 0 (PERIOD - April to September & October To March)

Submitted to RDSO Half Yearly – 1st May &1

st Nov.

PART-III - TRIPPING DATA

Tss For CB

No

Tripping

Target

Load

encroa

chment

Tree

Fault

Bird

Nest

Loco

Fault

Flash Over

to Less

clearance

Insulator

Flash

over

Grease

Deposit

at PTFE

External

Object

Tripping

Due to

Control

Flash

Over at

TSS

IOL

Voilation

at NS

Cross

Tripping

at TSS

Other

Specify

Railway……….

Division ……….

Depot…..

Ref : TIF-0014 Rev.0 (Period – November to October)

Submitted to RDSO Annually –15th

November.

PART-II - MAKEWISE BREAK UP OF TRACTION TRANSFORMERS

Sl.No. Division Number of Transformers

in service

Details of the transformers Remarks

MVA Rating Type of cooling ONAN/ONAF

Voltage

ratings

Date of

commissioning

78

C

AM

TE

CH

/E/1

4-1

5/P

SI-S

ch./1

.0

July, 2

01

4

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

Railway……….

Division ……….

Depot…..

Ref : TIF-0014 Rev.0 ( Period – November to October)


November.

PART-III - DETAILS OF TESTING KIT AVAILABLE FOR TRANSFORMER TESTING

Name of the Testing kit Numbers Available Working/ Defective Make Range

Railway……….

Division ……….

Depot…..

Ref : TIF-0014 Rev.0( PERIOD – ( April to September and October To March )

Submitted to RDSO Half yearly – 1st May and 1

st Nov.

PART-IV - FAILURE REPORTING OF THE TRANSFORMER

Sl.

No.

Div TSS

Loc

Make Voltage

Rating

MVA

Rating

Year of

Manufacture

Year of

Commissioning

Date of

Failure

Date & type

of last

maintenance

Details of

failure/Defects

including condition

i.e. on load or off

load

Action taken

by Railway to

rectify the

defect

Remarks

including

Details of past

failure, if any

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

July, 2

01

4

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

79

Railway……….

Division ……….

Depot…..



November.

PART-I - PERFORMANCE OF CAPACITOR BANKS

Div TSS

Loc.

Total

Kvar

capacity

Total

units

Break up of total units Number of

units in

service

Make of the

Capacitor

bank

Average age of

the Capacitor

bank

Whether

provided with

13% reactor No of

units

Each unit

Kvar

Each unit

voltage

Railway……….

Division ……….

Depot…..



November.

PART-II - PERFORMANCE MONITERING OF SERIES REACTOR

Div. TSS

Loc.

Total Kvar

capacity

% of the

Capacitor

bank capacity

Air/Oil

Type

Make of the

Reactor

Age of

The Series

Reactor

Failures if any With date of failure, Probable

reason of failure, corrective & preventive action

suggested etc

80

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

July, 2

01

4

R

eview o

f Ma

inten

an

ce Sch

edu

le for P

SI

Railway……….

Division ……….

Depot…..



November.

PART-III - DETAILS OF TESTING KIT AVAILABLE FOR TESTING

Div PSI depot Name of the

Testing kit

Numbers

available

Working Defective Make Range

Railway……….

Division ……….

Depot…..

REF- TIF 0015 Rev 0 PART IV( PERIOD – April To September and October To March

Submitted to RDSO Half Yearly – 1st Nov and 1

st May.

PART-IV : FAILURE REPORTING OF SHUNT CAPACITOR BANK

Division TSS Make Date of

Comm.

Date of

Failure

Details of

Failure

Probable

Reason of

Failure

Action

Taken

Corrective / Preventive Action

Suggested By Railway

Remarks

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

July, 2

01

4

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

81

Railway……….

Division ……….

Depot…..

Ref : TIF-0015 Rev.0( PERIOD – April To September and October To March)


st May.

PART-V : DETAILS OF THE PROTECTION PROVIDED FOR SHUNT CAPAVCITOR.

Railway……….

Division ……….

Depot…..

REF- TIF-0016 Rev 0, PART II (PERIOD – November to October)

Submitted to RDSO Annually – 15th

November

PART- II : YEAR WISE AND MAKE WISE BREAK UP OF CIRCUIT BREAKER

Sl.

No.

Year 220 kV 132 kV 25 kV

BHEL CGL ABB ALIND BHEL CGL ABB ALIND BHEL CGL ABB ALIND MG DP TP DP TP DP TP DP TP DP TP DP TP DP TP DP TP DP TP SP TP DP SP DP TP SP TP DP SP DP TP SP

DIVISION TSS Relay Make Relay Type CT Ratio Time delay (sec)

82

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

July, 2

01

4

Review

of M

ain

tena

nce S

ched

ule fo

r PSI

Railway……….

Division ……….

Depot……..

Ref : TIF-0016 Rev.0 ( PERIOD – April To September and October To March)


st May.

PART III - STATISTICS OF AC CIRCUIT BREAKER

Sl.

No.

Make Rated

voltage &

type

Serial No. &

year of

Manufacturing

Date of

commissioning

Date of

failure

No. of operation

before Failure/

Defect

Details of failure

/defect & location

of installation

Action taken by

Railway to

rectify the defect

Remarks

Railway……….

Division ……….

Depot…..

REF- TIF-0016 Rev 0, (PERIOD – November to October)


November

PART V - YEAR WISE AND MAKE WISE BREAK UP OF INTERRUPTOR

Sl.

No.

Year 220 kV 132 kV 25 kV

BHEL CGL ABB ALIND BHEL CGL ABB ALIND BHEL CGL ABB ALIND MG DP TP DP TP DP TP DP TP DP TP DP TP DP TP DP TP DP TP SP TP DP SP DP TP SP TP DP SP DP TP SP

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

July, 2

01

4

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

83

Railway……….

Division ……….

Depot…..

Ref : TIF-0016 Rev.0 (PERIOD – April To September and October To March)


st May.

PART VI - STATISTICS OF AC INTERRUPTOR

SN Make Rated

voltage

& type

Serial No. &

year of

Manufacturing

Date of

commissioning

Date of

failure

No. of operation

before Failure/

Defect

Details of failure

/defect & location

of installation

Action taken by

Railway to rectify

the defect

Remarks

Railway……….

Division ……….

Depot…..

REF- TIF-0017 Rev 0, (PERIOD – April To September and October To March)


st May.

PART -I - FAILURE FORMAT FOR SCADA

RLY DIV Section

with

TKM

Make Age of

Install-

-ation

Nos OF FAILURES (RTU) Nos OF RCC FAILURE Failure Rate Per 1000

TKM Per Month MODEM &

MIM Power

Supply

Per Month

I/o Cards

Master

Cards (CPU

Cards)

Synergy UPS Present 06

Month

Average

Previous

Year

Average Soft

Ware

Hard

Ware

5KVA

84

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

July, 2

01

4

R

eview o

f Ma

inten

an

ce Sch

edu

le for P

SI

Railway……….

Division ……….

Depot…..…..



November

PART -II - STATEMENT SHOWING MAKE WISE SCADA SYSTEM

Zone /

Div

Section

TKM

Supplier Year of

commis

sioning

Nos of RTU'S

RKM RCC PROFILE UPS

Make &

Rating Master Details PC / PDP / MP

FEP Details PC/ PDP/ MP

Work Station Details PC / PDP / MP

Operating

System

Railway……….

Division ……….

Depot…..

REF- TIF 0023 Rev.0 ( PERIOD – April To September and October To March)


st May.

PART II - INFORMATION ON AUXILIARY TRANSFORMER

S.N. Location Make KVA

Rating

S.N.&

year of

manufa

cturing

Date of

commissi

-oning

Date of

failure

Max

load in

amp on

AT

Last

maintenance

Detail of failure/

defect including

the value of

IR/BDV after

failure

Weather

condition

at the

time of

failure

Action taken

by railway to

rectify the

defect

Remarks

including

details of

past failure,

if any

Date IR/BDV

value

Review

of M

ain

tena

nce S

ched

ule fo

r PS

I

July, 2

01

4

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

85

Railway……….

Division ……….

Depot…..



November

PART -I - MEASUREMENT OF RESISTIVE LEAKAGE CURRENT OF SURGE ARRESTOR

As per RDSO TI/MI/0041 Rev. 1

Railway

Division Name of TSS/GSS

Voltage

class of LA

Make & year

of

manufacturing

of LA

Make & Year of

manufacturing of

equipment used for

measurement of resistive

leakage current

Voltage at the

time of each

measurement

Itotal Total

Leakage

current

(mA)

I3t Ir

86

CA

MT

EC

H/E

/14

-15

/PS

I-Sch

./1.0

July, 2

01

4

R

eview o

f Ma

inten

an

ce Sch

edu

le for P

SI

CAMTECH/E/11-12/Sch-PSI/1.0 87


ANNEXURE-I

Para 20207 of ACTM Vol. II Part-I

(The values from latest IS: 1866-2000 has been taken while ACTM table is having the values

from IS: 1866-1983)

APPLICATION AND INTERPRETATION OF TESTS ON TRANSFORMER OIL IN

SERVICE

S.

No.

Tests Value as per IS:

1866-2000

permissible limits

To be re-

conditioned

To be

replaced.

1. Electric strength

(Breakdown voltage)

Below 72.5 kV

72.5 kV and less than 145 kV

145 kV and above

Min.

30 kV

40 kV

50 kV

Less than the

value

specified

--

2. Specific resistance

(Resistivity) Ohm-cm at

90°C

Above

1x 1012

Between

0.1 x 1012

to

1 x 1012

Below

0.1 x 1012

3. Water content

Below 145 kV

Above 145 kV

Max.

40 ppm

20 ppm

Greater than

the value

specified in

column 3

--

4. Dielectric dissipation factor,

Tan delta at 90 0C

0.2 or less -- Above 0.2

5. Neutralisation value mg

KOH/ g of oil.

0.3 or less -- Above 0.3

6. Interfacial tension N/ m 0.015 or more -- Below 0.015

7. Flash point in 0 C 140 or more 125 and above

but below 140

Below 125

8. Sludge Non- detectable,

Results below

0.02% by mass

may be neglected

Sediment Perceptible

sludge

9. Dissolved Gas Analysis

(DGA)

Refer Annexure

2.04 of ACTM

Vol.II Part-I

88 CAMTECH/E/11-12/Sch-PSI/1.0


ANNEXURE-II

` PHYSICAL PROPERTY OF SF6 GAS

1. Molecular weight 146.07

2. Melting point -50.7 deg. C

3. Sublimation Temperature -63.8 deg.C

4. Critical Temperature 45.547 +0.003

5. Critical pressure 38.55kgf/cm2

6. Critical dencity 0.730 g/cm2

7. Dielectric constant at 25 deg.C 1atm 1.002

8. Thermal conductivity 3.36x10-5

9. Specific heat ratio 1.07

10. Density at 20 deg.C

at 0 kgf.cm2 - g 6.25gm/lit

at 1 kgf.cm2 - g 12.3

at 5 kgf.cm2 - g 38.2

at 10 kgf.cm2 - g 75.6

at 15 kgf.cm2 - g 119.0

11. Solubility

In oil 0.297 CC/CC

In H20 0.001 CC/CC

of H20 0.035 + 0.01

at 30 deg.C gm/gm

12. Cp 23.22 Cal/Mole deg.C



ANNEXURE ‘III’

LUBRICATION FOR CGL CIRCUIT BREAKER/INTERRUPTER

The correct lubricant should be applied and used during maintenance schedule.

1. Application of lubricants

Dariana Grease #2 Linkage in SF6 gas & air

Shell oil co. Mechanism

Microcarbon grease Interrupter contacts

Kyodo oil Co.

2. Procedure

a. Clean the various parts of the switchgear to be greased. Remove the former

grease oil, water and dust.

b. Keep the lubricants and greases clean and free of contaminants. This can be

confirmly by feeling the grease between the fingers.

c. Apply the grease thinly and uniformly to the parts.

d. Assemble the parts before the greases or parts become contaminated with dust

or dirt.

ANNEXURE ‘IV’

APPLICATION OF ELECRTRICAL JOINT COMPOUND FOR CGL CIRCUIT

BREAKER/ INTERRUPTER

This application is electrical joint compound to connect high voltage connections

made of aluminium.

1. Joint compound material : Jointal-Z (Green)

2. Aluminium forms a thin film of oxide on its surface when exposed to air, and very

quickly develops the film. This oxide film protects the metal from further

corrosion, however, the film of oxide has a high value of resistance and acts as an

insulator. The oxide film must be removed and joint compound should be applied

to the connection surfaces in order to maintain the efficiency of the metals as a

connector. The joint compound also helps in penetrating the film of oxide during

the cleaning process.

3. Procedure

Apply a coat of the joint compound to the connecting surfaces of the

connectors.

Remove the oxide film with ‘Scotch-Brite’ or nonmetallic abrasive paper.

Wipe off the joint compound that contains metal particles.

Apply new joint compound thinly to the connecting surfaces within three

minutes after the previous compound is removed. Bolt any connectors together.

Remove any excessive joint compound.

Note : Do not use a brush or abrasive paper on silver plated or thin plated

connectors.

Lightly buff the surfaces to a bright finish.



ANNEXURE ‘V’

WEATHERING SEALING FOR CGL CIRCUIT BREAKER/ INTERRUPTER

This instruction is cover weather sealing of joints and hardware to prevent corrosion of

the equipment. Outdoor high voltage circuit breaker is exposed to all kinds of weather. Moisture

and other pollutants react to cause serious damage to the equipment. The following weather

sealing procedure is recommended to reduce the corrosion and extend the life of the equipment.

1. Weather sealant material anabond 680

2. Application

The weather sealant should be applied sufficiently to the entire area to eliminate the

penetration of moisture into the joints.

The surface and parts to be sealed should be clean – and free from any deposit of the

solvent used for cleaning.

Where the sealant is applied between mating surfaces, the assembly of parts should be

completed within one hour before the sealant hardens. The minimum set time is one hour for

1mm (0.025in) layer.

3. General cautions

Do not mix the weather sealant with any other grease or water.

Smooth out the weather sealant which extrudes from flange surfaces.

Replace the cap to the tube of weather sealant before storing.

4. External joints

The joint between the flanges and the hardware, particularly in the horizontal

position, should be sealed with the weather sealant.

ANNEXURE ‘VI’

LUBRICATION FOR ABB CIRCUIT BREAKER / INTERRUPTER

The correct lubricant should be applied and used during maintenance schedule.

Oil ‘A’ Mobil 1(481127) 5w-30:

Thin lubricating oil is use for precision parts in operating mechanism and air-blast

circuit breaker and also for re-lubricating of bearing, which can not be lubricated with grease

G without dismounting -e.g. links and link gears. Viscosity at 400C: 62-65 cSt.

Oil ‘C’Energal ISH -V:

Circuit-breaker oil with viscosity~17 cSt at +200C. It is suitable only for temperature

> -100.

Oil ‘D’ Circuit Breaker oil Unlvolt 42 (44):

Circuit-breaker oil with viscosity~6.0 cSt. at +200C. It is used as oil in dashpots. For

dashpots with the letter “S” stamped on the cover - oil “S” should be used.

Oil ‘S’ DC 200 Fluid 200CS:

Silicon oil intended for oil dashpots in heavy operating mechanisms. Only dashpots

with the letter “S” stamped on the cover should be filled with this oil.



ANNEXURE ‘VII’

GREASE FOR ABB CIRCUIT BREAKER / INTERRUPTER

The following types of lubricant grease are used during maintenance schedule.

Grease ‘G’ 71 BEP Synthetlc grease:

Low temperature grease is use for all types of bearings, gears and worm gears as well as

valves in air-blast circuit-breakers and also suitable for lubrication of silver plated contacts in air

(e.g. contacts in dis- connectors).

Also used when greasing O-rings made from nitrile rubber and as a crevice corrosion

prevention.

Grease ‘N’ Fomblin OT 20:

The lubrication of moving contacts in SF6 circuit breakers is used (e.g. puffer cylinders). A

very thin layer of the grease shall be rubbed on the sliding surface of the contacts.

Grease ‘L’ ASEOLSYLITEA 4- 108:

Low temperature grease specially suitable for lubricating of fine mechanics-e.g. catch devices

in operating mechanism which shall operate in strong cold.

Grease ‘M’ Isoflex Topas NB 62:

Low temperature grease for long-duration and permanent lubrication is used in worm gears

and other machine elements. It is prevents wear and corrosion.

Grease ‘P’ Shell Vaseline B401:

Vaseline for treatment of contact surfaces in current conductor joints.

Grease ‘R’ Molykole Longterm 2 Plus:

EP-grease is used for heavily-loaded roller bearings, slide bearings, cam discs and catches

(Lithium grease. Solvent refined mineral oil with lithium soaps and molybdenum disulphide) in

operating mechanisms type FSA.

Grease ‘S’ FS- 3451No:

Fluoro-silicone grease for greasing of O-ring made from EPDM and as a corrosion

prevention of gaps in circuit-breakers type ED.

Grease ‘SV’ Electrical Grease :

Grease for lubricating moving contacts, silver plated connections and brushed aluminium

surfaces in fixed joints outdoors.



ANNEXURE ‘VIII’

AN APPROACH TO EQUIPMENT FAILURE INVESTIGATION

i. On Failure Aspects

1. Occurrence

2. Date of occurrence

3. Past similar occurrences if any

4. Analysis of failure i.e. why did it happen?

5. Whether the rate of failure is worse than other installations?

ii. On Maintenance Aspects

1. Whether schedule maintenance & required testing have been carried out on the failed

equipment as per norms stipulated?

2. Does the frequency of maintenance require change?

3. Was the work properly supervised?

4. Was any RDSO modification required to be done?

5. Is any modification possible to avoid failure?

iii. About Staff

1. Is the quality of work done satisfactorily?

2. Is the skilled staff properly trained to carry out the work?

3. Is the SMI available with them?

4. Are proper tools available with the staff?

iv. About Material

1. Is the material received from approved source?

2. Whether the material is as per approved specification?

3. Can a better material be used?

vi. About Testing

1. Is the testing equipment available?

2. Could testing procedure be improved to weed out the failures?

3. Whether testing equipment are calibrated?

vii. General Points

Whether following points were checked / performed properly?

1. Proper contact

2. Clearances

3. Capacity

4. Proper contact pressure

5. Crack detections

6. Cleaning

7. Proper connections/alignment

8. Cross checks/super checks

viii. Any other Findings not covered in the above



ANNEXURE ‘IX’

RUBBERISED CORK GASKET & RUBBER ITEM USED IN TRD

Different types of Rubberized Cork gaskets/components are used in the Power Supply Installation

(PSI) mainly in transformers. It is generally agreed that bad quality & improper fitment of Gaskets in

the transformers is un-desirable because of various long term adverse effects on dielectric integrity

such as:

Reduction in dielectric strength of oil.

Accelerated ageing of insulation

Bubble generation in the solid insulation during overloads

Ageing factor

The problem of oil leakage from the transformer bushings and covers are also mainly due to use of

non standard/ non specified gaskets/ ‘O’ rings during assembly. To prevent the problem RDSO has

issued a technical circular no. ELRS/TC/0076/ Rev. ‘0’ dtd. 17.09.2002 and its Rev.1 dtd.

22.02.2013.

In Nitrile bonded cork gasket, the size of cork granules shall be of ‘fine’ category as mentioned in

clause 3.2 of IS 4253 (Pt.2) 2008. The NBC gasket shall be of type RC70-C. The characteristics of

RC70C and their values are given below as given in TC 76 Rev. 1:

S.No. Characteristics Value Test Method

1. Hardness (IRHD) Shore A 70 ± 5 IS 3400 (part 2) 1995

2. Dimensional changes, percent, Max. 1.5

IS 4253 (part 2) 2008

3. Tensile strength, kPa Min. 1550

4. Compressibility (%)

(at 2800 kPa) percentage

25 - 35

5. Recovery, percent, Min. 80

6. Compression set, percent, Max. 85

7. Chemical test on water extract

(a) pH, where applicable

(b) Chloride content (as chloride ion)

(c) Sulphate content (as sulphate ion)

5.0 – 8.5

0.2 percent, Max.

0.2 percent, Max.

8. Volume change in transformer oil as

per IEC 60296, 70h/ 100°C

Max. 8

CORK COMPOSITION SHEET AND SOME CHECKS

(Ref: IS 4253, part 2, 2008)

Cork composition sheets for gasket are made by the compounding of granular cork with natural or

synthetic rubber.



Types of Cork sheet : Three types

Type ‘A’ - Non oil resistant

Type ‘B’ - Good resistance to oil

Type ‘C’ - Very good resistance to oils & petrol

Further each type is classified in three grades, i.e. RC50, RC70,

RC80 according to hardness. Hardness can be checked by Brinell

hardness tester, it shall be within specified limit i.e. designed

hardness ± 5 .

The cork sheet shall be free from cracks or pinholes and shall be

capable of being cut or punched without cracking or tearing.

For fine grain size : Cork granules passing through 1.00 mm IS

Sieve and retained on 425 micron IS Sieve.

The permissible variation in thickness at any point of the sheet

shall be ± 10 percent for thickness upto 2.50 mm and ±0.25 mm

for thickness above 2.50 mm.

For checking flexibility: Three test specimens where possible 25 mm wide and of suitable

length shall be cut from each sheet in the sample from widely separated position. The test

specimens shall be bent through 180° round a mandrel of diameter 3 times the thickness of

the specimens for materials upto 3 mm thickness, or 4 times the thickness of the specimen for

material over 3 mm thick. The flexing being carried out at a rate of 1minute through 180°

using finger pressure at ambient temperature. There shall be no breakage through the

granules of cork or separation of the granules.

For fluid resistance test: For type ‘C’ required in electrical industry, immersion test may be

conducted in transformer oil as per IS 335 for 70 hrs. at 90 degree C to 100 degree C, in such

cases change in volume should not exceed 8 percent.

FOR MORE DETAILS ABOUT OTHER TESTS, PLEASE REFER IS 4253, PART 2, 2008

MARKING

Cork composition sheets shall be marked with the following:

• Manufacturer’s name or trade mark

• Date of manufacture

• Grade



PACKING

Cork composition sheets/ gaskets shall be suitably packed to prevent damage. Preferably shall be

kept in HDP (high density polythene) bags.

STORAGE

Cork composition sheet shall not be stored under conditions of temperature, humidity or for

reasonable period of time, which are likely to cause deterioration.

Knowledge about storage conditions of rubberized cork items will be useful to avoid

premature failure.

Many rubberized cork products and components are stored for a period before being put into

service and thus it is important that they are stored in conditions that minimize unwanted

changes in properties. Such changes may result degradation such as excessive hardening,

softening, cracking, crazing and other surface effects. Other changes may be because of

deformation, contamination or mechanical damage.

GASKET SELECTION

• Always use a good quality gasket from a RDSO approved manufacturer/ supplier, because

the cost of a gasket is insignificant when compared to the cost of failure or safety

consideration.

• Cutting of Gaskets: Use a good cutter

• Never try to cut out a gasket by hammering material against flange.

• Ensure the gasket is of the correct size.

• Cut (preferably punching) the bolt holes slightly larger than the bolt shaft diameter.

• Ensure that the inside diameter of the gasket is not less than the inside diameter of the process

line.

HANDLING OF GASKETS AND GASKET MATERIALS

• Carry Gaskets Carefully, Ideally with some form of protective cover.

• Do not Bend or Buckle.

• Do not damage the Gasket surface.

CONCLUSION

• A gasket must create a seal and hold it over a long period of time.

• It is prudent to include gasket testing in the quality assurance programme.

• It is not only good gasket but proper installation techniques are key requirements.

REMEMBER

During any activity by the shed/ shop involving opening of the transformer tank cover or

removal of bushings, the old gaskets has to be necessarily removed and replaced by a new

gasket. (Ref: RDSO L.No. EL/3.2.1 dtd. 03.05.2001)

Always use a good quality rubberized cork item from a RDSO approved manufacturer

to ensure long life of gasket, because the cost of a rubberized cork item is insignificant

when compared to the cost of traffic block due to a supply failure.



As per TC 076 (Rev.1- dtd 22.02.2013) the cork sheet gasket material shall be NBC -

Nitrile bonded cork Gasket as per IS:4253 (Part 2): 2008 and following are the sources of

supply for NBC gaskets for locomotive transformers:

1. Cortica Mfg.(I) Pvt.Ltd.

Plot No. 105, Sidco Inds Estate, Thirumazhisai. Madras

2. NU-Cork Products (P) Ltd., E-370,

Phase-I, RIICO Indl. Area, Bhiwadi - 301019.

3. Talbros Pvt. Ltd.

Plot No. 60, Sector 6, Faridabad

4. Bharat Corrub Industries LLP

749/8 GIDC Industrial Estate, Makarpur, Baroda 390010

5. Indian Cork Industries, Khasara No. 33A, Modern Indistrial Estate, opp, Bahadurgarh

Chamber of Commerce, Delhi Rohtak Road, Distt- Jhajjar(Haryana)



REFERENCES

1. Manual of AC Traction Maintenance and Operation Volume II (Part–I)

Fixed Installations 1994

2. RDSO’sSpecificationsno.TI/MI/00038REV.1,TI/MI/00026Rev.2,

TI/SPC/PSI/CLMNA/0030, TI/MI 0041 REV – 0, TI/MI/00039 Rev 1

3. Comments & Suggestion received from participant during seminar held on

05th May 2014 at CAMTECH Gwalior.

4. Study of maintenance practices in the field.

5. Maintenance Schedules received from various Railways WR, CR, WCR

SCR, SR etc.

6. Details of Thermo Vision Camera 28th MSG TRD at SCR on Feb 2011

item no. 28.19

7. Instructions maintenance manual of M/s. CGL Ltd., ABB Ltd. and Allind

8. Presentation given by M/s. Nu Cork Product Pvt. Ltd Bhiwadi during

seminar held on 05th May 2014 at CAMTECH Gwalior.



To upgrade maintenance technologies and

methodologies and achieve improvement in

productivity, performance of all Railway

assets and manpower which inter-alia

would cover reliability, availability,

utilisation and efficiency.

If you have any suggestions and any specific

Comments please write to us.

Contact person : Director (Elect.) Postal Address : Indian Railways

Centre for Advanced Maintenance technology, Maharajpur, Gwalior. Pin code – 474 005

Phone : 0751 – 2470740

0751 – 2470803 Fax : 0751 – 2470841 Email : [email protected]

OUR OBJECTIVE

Hkkjr ljdkj GOVERNMENT OF INDIA MINISTRY OF RAILWAYS

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