Check list ACB, VCB, OCB, LT PANEL

Air Circuit Breaker (ACB): 

Panel 11 KV VCB type

• Cleaning of breaker with CRC-226
• Removal of old Grease and re-greasing the same with recommended grease
• Check condition of arcing contact and gap between fixed and moving arcing contracts shall be checked.
• Check condition of arcing contact and gap between fixed and moving arcing contracts shall be checked.
• Checking the reset mechanism, tripping of breaker through push button.
• Checking the reset mechanism, tripping of breaker through push button.
• Checking tripping of ACB through protection release.
• Checking presence and proper tightening of hardware.
• Checking presence of all cir clips.
• Checking condition and alignment of jaw contract with cradle terminals
• Checking condition of ACB wiring and replace if required.
• Checking and adjusting gap between hylam sheet and side plate.
• Checking proper closing of all poles together.
• Checking working of anti pumping device in case of EDO ACB.
• Checking alignment of SIC and its operation.
• Checking scrapping earth alignment.
• Checking condition of arc chutes.
• Checking U/V release pickup and drop off.
• Checking ACB tripping through Shunt release.
• Checking motor operation in case of EDO ACB.
• Checking closing coil operation in case of EDO ACB.
• Checking continuity and proper changeover of aux contract block.
• Checking IR between phases – phase (ACB Closed condition).
• Checking IR between phases – earth (ACB closed Condition).
• Checking IR between phases – earth (ACB in open condition).
• Setting of release as per the load.

 After the inspection, the ACB shall be checked for proper termination by mv drop Test

Vacuum Circuit Breaker (VCB):

• Cleaning of Vacuum Circuit Breaker with CRC-226
• Removal of old grease and re-greasing the same with recommended grease
• Check condition of SIC Contacts
• Checking condition and alignment of jaw Contact
• Checking and proper tightening of hardware
• Checking proper closing of all poles together
• Checking of breaker tripping through push button
• Checking and adjusting gap between hylam sheet and side plate
• Checking motor operation in case of EDO.
• Checking of auxiliary contacts continuity proper change over
• Checking presence of all circlips
• Checking IR between phase – phase (VCB closed condition)
• Checking IR between phase – earth (VCB closed condition)
• Checking IR between phase – earth (VCB in Open condition)
• Any faculty spare replace by new one, which will be charged extra.

Oil Circuit Breaker (OCB):

• Cleaning of Oil Circuit Breaker with CRC-226
• Removal of old grease and re-greasing the same with recommended grease
• Check condition of SIC Contacts
• Checking condition and alignment of jaw Contact
• Checking and proper tightening of hardware
• Checking proper closing of all poles together
• Checking of breaker tripping through push button
• Checking and adjusting gap between hylam sheet and side plate
• Checking motor operation in case of EDO.
• Checking of auxiliary contacts continuity proper change over
• Checking presence of all circlips
• Checking IR between phase – phase (OCB closed condition)
• Checking IR between phase – earth (OCB closed condition)
• Checking IR between phase – earth (OCB in Open condition)
• Any faculty spare replace by new one, which will be charged extra 

  

 LT Panel: We do following during regular maintenance of LT Panel

• Cleaning of Panel Breaker with CRC-226
• Check condition of Bus bars
• Checking condition and alignment of jaw Contact
• Checking and proper tightening of hardwares
• Checking of breaker tripping through push button
• Checking motor operation in case of EDO.
• Checking of auxiliary contacts continuity proper change overs
• Checking presence of all circlips
• Checking IR between phase – phase (ACB closed condition)
• Checking IR between phase – earth (ACB closed condition)
• Checking IR between phase – earth (ACB in Open condition)
• Checking of Contactor NO NC Point
• Checking of ad on block NO NC Point
• Checking of Control Wiring
• Checking of Thimble Tightness
• Checking of MCCB
• Checking o MCB
• Any faculty spare replace by new one, which will be charged extra.

Control Wiring: We do following during regular maintenance of Control Wiring

• Checking of All Control Wiring
• Checking of Contactor in NO/NC Point
• Checking of Glass Relay in NO/NC Point
• Checking of MCB Terminals
• Checking of RCCB Terminals
• Checking of Contactor Coil Resistance
• Checking of auxiliary Contact
• Checking of thimble of Terminals
• Checking of indicator of Panel
• Checking selectors switch in NO/NC Point
• Checking of TNC Switch in NO/NC Point
• Checking of Fuse Link Terminals
• Checking of Timer Relay Terminals
• Checking of Amp Meter Tightening at Terminals
• Checking of voltage meter Tightening at Terminals