ABB DCGear Product Manual page 29

M A I N T E N A N C E
Check auxiliary circuits and protection relays
Activity:
Condition – safety instruction:
Risks:
Ordinary maintenance of rectifier trolley
Activity:
Condition – safety instruction:
Risks:
Ordinary maintenance of circuit breaker trolley
Activity:
Condition – safety instruction:
Risks:
WARNING
Possible tripping protection.
Before making this operation make sure that the control
system of pts being in safety position.
The auxiliary circuits of command and control, such as relays, auxiliary
switches, buttons, lamps, etc., generally do not require maintenance,
but only regular checking of their functionality. SHEET 15. Test the
functionality of the equipment, through the forcing of the auxiliary
circuits and simulation of external commands (refer to the functional
drawing for this forcing mode).
The protection relay (DC-PRO); relay 32 SHEET 09, generally do not
require maintenance, but only regular checking of their protection
function. Check the chain protections, through the simulation of the
intervention of each relay, in all modes of protection. Refer to the
technical documentation of every relay regarding specific checks to be
performed.
De-energize the power circuits and e connected to ground.
Equipment on trolley in position "DISCONNECTED".
Danger-high voltage and mechanical parts in movement brusque.
The activity may cause unwanted tripping of the protections. Make sure
that the control system of the substation is placed in safety conditions
De-energize all circuits. Use proper precautions.
Make the preventive maintenance described in the manual of the
rectifier trolley Refer to the product documentation for the necessary
activities and spare parts.
De-energize the power circuits and e connected to ground.
Equipment on trolley in position "DISCONNECTED".
Handling of heavy loads.
Use extreme caution and follow the necessary procedures for the
handling of heavy loads.
Make the preventive maintenance described in the manual of the circuit
breaker trolley Refer to the product documentation for the necessary
activities and spare parts.
De-energize the power circuits and e connected to ground.
Equipment on trolley in position "DISCONNECTED".
Handling of heavy loads.
Use extreme caution and follow the necessary procedures for the
handling of heavy loads.
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