- POWER TRANSFORMER
- AUXILIARY TRANSFORMER
- CURRENT TRANSFORMER
- POTENTIAL TRANSFORMER
- CIRCUIT BREAKER
- ISOLATOR
- LIGHTING ARRESTER
- POWER CABLE
- PROTECTION RELAYS
- AUXILIARY RELAYS
- METERS
- EARTH PITS
POWER TRANSFORMER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Internal Protections Check (WTI, OTI, Buchholz Relay, PRV & MOG) Insulation Resistance / Polarization Index Check (Digital IR Tester, Make: Megger, Model: BM5200) Magnetizing Current, Magnetic Balance, Voltage Ratio & Short Circuit Check Winding Resistance (TWRM, Make: SCOPE, Model: TRM104) Vector Group Check Capacitance & Tan Delta Measurement Test (Tan Delta, Make:Megger, Model: DELTA 4110) Oil Filtration until BDV is achieved (withstand 60 KV/min as per IS) EVERY FOUR YEARS OR WHEN SHIFTED Sweep Frequency Response Analysis (SFRA, Make:Megger, Model: FRAX 101) Oil Insulation Diagnostics Test (DIRANA, Make:Megger, Model: IDAX 300)
* Testing will be done using conventional test kits & special kits will be used where ever required
AUXILIARY TRANSFORMER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE
Insulation Resistance (Digital IR Tester, Make: Megger, Model: BM5200)
Winding Resistance (TWRM, Make: SCOPE, Model: TRM104)
Voltage Ratio Test (Transformer Test Board Make: 
)
Magnetic Balance & Magnetizing Current (Transformer Test Board Make: )
Vector Group
Oil Filtration until BDV is achieved (withstand 60 KV/min as per IS)
Change Slica Gel When color changes to white from blue
* Testing will be done using conventional test kits & special kits will be used where ever required
CURRENT TRANSFORMER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Digital IR Tester, Make: Megger, Model: BM5200) Winding Resistance Measurement,Polarity Check Current Ratio Check Knee Point Voltage Check for Special Class cores (PS Class) Capacitance & Tan Delta Measurement (Above 33 KV) (Tan Delta, Make:Megger, Model: DELTA 4110)
* Testing will be done using conventional test kits & special kits will be used where ever required
POTENTIAL TRANSFORMER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Digital IR Tester, Make: Megger, Model: BM5200) Winding Resistance Measurement Voltage Ratio Check Capacitance & Tan Delta Measurement (Above 33 KV) (Tan Delta, Make:Megger, Model: DELTA 4110)
* Testing will be done using conventional test kits & special kits will be used where ever required
CIRCUIT BREAKER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Digital IR Tester, Make: Megger, Model: BM5200) Coil Resistance of Closing, Tripping & Motor Coil Contact Resistance Check (CRM, Make: SCOPE, Model: CRM100B) Timing Check(Open, Close & Close-Open) (Time Interval Meter, Make:SCOPE, Model: SCOTM3K) Dynamic Contact Resistance Measurement Test (Above 220 KV) (Make:SCOPE, Model: HISAC Ultima)
* Testing will be done using conventional test kits & special kits will be used where ever required
ISOLATOR
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Digital IR Tester, Make: Megger, Model: BM5200) Contact Resistance Check (CRM, Make: SCOPE, Model: CRM100B)
* Testing will be done using conventional test kits & special kits will be used where ever required
LIGHTING ARRESTER
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Digital IR Tester, Make: Megger, Model: BM5200) Check Counter Operation ( By Voltage Method; Upto 3Kv)
* Testing will be done using conventional test kits & special kits will be used where ever required
POWER CABLE
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Insulation Resistance Test (Before & After Hi-Pot Test) (Digital IR Tester, Make: Megger, Model: BM5200) Hi-Pot Test (HV Test Kit, 30/40kv ac/dc & 70/80 kv ac/dc, Make: AJ)
* Testing will be done using conventional test kits & special kits will be used where ever required
PROTECTION RELAYS
ANNUAL CHECKS & PREVENTIVE MAINTENANCE As per approved setting all protections shall be checked by secondary injection method Output contact changeover check. Check LED function as per configuration
* Testing will be done using conventional test kits & special kits will be used where ever required
AUXILIARY RELAYS
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Check Pick-Up Voltage (AC/DC Power Source) Check Drop-Off Voltage (Only for Auto Reset Relays) Contact Changeover Check. Coil Resistance Check
* Testing will be done using conventional test kits & special kits will be used where ever required
METERS (OFFLINE & ONLINE)
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Measurement of Voltage, Current, Frequency & Power Factor) Check Accuracy of Meter (Active / Reactive / Apparent) Error Calculation
* Testing will be done using conventional test kits & special kits will be used where ever required
EARTH PIT / EARTH MAT
ANNUAL CHECKS & PREVENTIVE MAINTENANCE Individual & Grid Resistance Value Measurement ( Before & After Reconditioning) (Digital Earth Tester, Make: Megger/Waco) Reconditioning of Earth Pit Earth Mat Integraty Test (Make:OMICRON, Model: CPC 100)
* Testing will be done using conventional test kits & special kits will be used where ever required