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P L A C I N G S W I T H C G E A R I N TO S E R V I C E
—
Placing switchgear into service —
safety precautions
Danger: Turn off power ahead of switchgear before
performing any inspection or maintenance
operations.
Check incoming line terminals to verify that the
equipment is de-energized and grounded.
Check outgoing terminals to ensure that no back-
feed condition exists.
The circuit breakers should be in the TEST position.
When working on switchgear, de-energize and
ground the main-bus.
Before energizing any part of the switchgear, make
a complete check of the mechanical operation of all
devices. Remove blocking wedges from relays,
circuit breakers, meters, etc. Manually operate all
circuit breakers and relays. Moving parts should
not bind. Verify that there are no foreign objects in
the equipment. Use compressed, clean, dry air to
clean all inside and outside surfaces.
Make incoming and outgoing power connections
after all other connections are complete. A note on
the connection diagram indicates devices that are
phase sensitive. Verify the phase sequence of the
incoming power source before making
connections.
Notice: Never open circuit the secondary circuits of
energized current transformers.
The contact surfaces of the bus at bolted joints are
plated. Clean contact surfaces with a clean cloth
and an OSHA-approved solvent. Bolt the bus
together. Conductivity of a bolted joint depends
on the pressure or torque applied.
All bolted joints must be torqued per the values
in appendix A — target torque values.
Energizing the main bus
Verify that all door and panel hardware is secure.
After completing the control circuit checkout,
energize the control equipment main bus.
Verify the settings and integrity of all relays,
regulators and other devices for proper operation
of loads.
Energize the incoming bus to the main circuit
breaker of the equipment. Confirm correct
operation of all relays, regulators and other
devices for proper operation of loads.
Energize the separate control power source,
if furnished.
Energize the switchgear main bus by closing the
main circuit breaker. Observe if operation of all
relays, regulators and other devices for proper
operation of loads is correct.
Rack the circuit breakers to the CONNECTED
position.
Close the desired feeder and tie-breaker circuit
breakers.
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