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2. Equipment and Installation Inspection Items

Step Description of what you should do
2.1 Inspect switchgear bus bar connections for tightness by verifying that the torque meets manufacturer’s specifications. Verify that connection hardware is consistent with the Owner’s project specifications.
2.2 Inspect switchgear bus supports for cleanliness and tightness.
2.3 Inspect ground connections to switchgear ground bus.
2.4 Inspect operation of the drawout mechanism including mechanical interlocks, position indicators, and safety features.
2.5 Inspect operation of shutter devices.
2.6 Inspect operation of PT disconnecting and grounding mechanisms.
2.7 Inspect circuit breaker insulating parts for cleanliness and dryness.
2.8 Inspect electrical contact surfaces of air circuit breaker for cleanliness and smoothness. Lubricate stationary contact surfaces per manufacturer’s
recommendations.
2.9 Inspect contact wipe and alignment of air circuit breaker and verify that it is in accordance with manufacturer’s recommendations.
2.10 Inspect vacuum breaker mechanical adjustments and critical dimensions in accordance with manufacturer’s recommendations.
2.11 Inspect circuit breaker manual operation (maintenance closing procedure) to verify that all parts are free and that they work smoothly.
2.12 Inspect operation of breaker mechanical trip function.
2.13 Inspect lubrication of breaker-operating mechanism and all other breaker moving parts.

3. Testing Requirements

Step Description of what you should do
3.1 Test insulation resistance of switchgear bus with a 1-minute test (phase to phase and phase to ground).
3.2 Test insulation resistance of all instrument transformers with a 1-minute test at applicable voltage.
3.3 Test insulation resistance of each circuit breaker (closed position) with a 1-minute test (phase to phase and phase to ground).
3.4 Test circuit breaker contact resistance with micro-ohmmeter.
3.5 Test dielectric strength of each medium-voltage circuit breaker (closed position) with DC high-potential unit using the step voltage method and with final voltage value according to the table in paragraph 5.5, unless specified otherwise by the Owner. (Isolate and test each phase to ground with the other two-phase terminals connected together and to ground.)
3.6 Test integrity of each vacuum interrupter on a vacuum circuit breaker in accordance with manufacturer’s instructions.
3.7 Calibrate and test each protective relay. Settings on devices shall be in accordance with the approved relay settings summary or coordination study.
3.8 Test each CT secondary circuit by applying current to CT secondary circuit with CTs disconnected and by verifying operation of all applicable relays and metering devices. Perform a ratio-verification test using the voltage or current method in accordance with ANSI C57.13.1.
3.9 Test each window-type ground CT and their circuits by applying current to conductor passed through the window.
3.10 Test each PT secondary circuit by applying voltage to PT secondary circuit, with the PTs disconnected, and then by verifying the operation of all applicable relays and meters.
3.11 Test voltmeter, ammeter, and related selector switches.
3.12 Test operation of all space heaters, including switching and indicating devices.
3.13 Perform circuit breaker minimum voltage trip test. Trip unit should be operable at 40 percent of nominal voltage.
3.14 Verify that each circuit breaker opening time meets the manufacturer’s specifications.
3.15 For double-ended switchgear, test phasing after energizing but before closing the tie breaker.

4. Function Test Items

Step Description of what you should do
4.1 Function-test circuit breaker in test position:

  1. Close and trip circuit breaker from its local and remote control devices.
    Verify operation of all auxiliary devices by functional testing.
  2. Trip circuit breaker individually from each local protective device.
  3. Test any special circuits such as main-tie-main controls.
4.2 Function-test circuit breaker in normal operating position before energization of bus.
4.3 When resistance-grounding systems are installed, function test the equipment using the available protection/alarm test features.