Conduct Breaker Inspection, Test and Adjustment in accordance with procedural and operational experience to include:
• Check for abnormal assembling of mechanism parts
• Lubricate appropriate mechanism parts
• Inspect mechanism for dust and foreign materials
• Check mechanism C-rings, spring pins and divider pins for wrinkled or missing
• Check control circuit wiring for loose connections or loose parts
• Check closing tripping device moveable parts and check for discoloration of coil
• Check control circuit Aux switches links and contacts
• Check main circuit connections and for corrosion or discoloration
• Check vacuum integrity
• Check for normal operation of the Aux device switching indicator
• Perform insulation resistance checks on the main circuit and the control circuit
• Perform a Withstand Voltage test on the main circuit
• Perform operating characteristics test for trip/close, trip-free, and minimum operating voltage
• Check contact finger sectional traces for heat or discoloration, arcing damage, and condition of grease on the contactor surface
• Check contact spring for sectional traces of heat or discoloration, arcing damage, transformation, or mechanical crack of a coil
• Check VCB and cradle terminal for sectional traces of heat or discoloration, arcing damage, and mutual eccentricity between terminals
• Check main circuit contact resistance after drawing out of the VCB.
• Manual operation - feel for binding (experience needed)
• Perform and record as-found electrical open and close test
• Perform pre-disassembly functional tests and visual inspection
• Remove front covers, phase barriers (if present) and arc chutes
• Replace lubricant where accessible
• Lubricate contact stabs and easily accessible pivot points and primary contacts if required
• Generally clean and inspect all accessible parts and surfaces
• Inspect for: pitting or corrosion on primary contacts; damaged, loose, or missing fasteners and setscrews; electrical tracking; cracked welds; rust or corrosion; cracked or burned arc chutes; hard lubricant; secondary control block damage or misalignment; worn or bent mechanical linkage, general cleanliness; wiring harness and protective relay damage.
• Replace known parts subject to wear-out or required by procedure
• Verify adjustments
• Perform insulation resistance tests
• Calibrate protective devices as required
• Perform overcurrent trip test
• Perform as-left electrical open and close test – PMT