Rockwell Automation 8720MC 8720MC Regenerative Power Supply User Manual - Manual (Page 114)

1. Turn OFF the input power to the 8720MC-RPS Regenerative
Power Supply and wait until "POWER" lamp goes OFF.
2. Verify that the DC bus voltage is zero and the DC bus
capacitors are completely discharged.
3. Check the following:
• Check that no terminal is loose and that termination to the
connectors is correct.
• Check that the incoming power voltage is correct.
• Check that the unit was installed correctly.
• Verify that all the coils possibly generating electrical noise
around the unit, such as relays, solenoid-valves, and
magnetic brakes are provided with surge suppressors.
8720MC-RPS Regenerative Power Supply Does Not Run
9-2 Inspecting Trouble and Recovering
Preliminary Review
Troubleshooting Flow
Charts
The unit does not run.
Power supply ON?
YES
YES
YES
YES
Check the following:
• Circuit breaker
• Protection fuse
• Wiring
• Power supply
Check wiring for the sequence
signals.
Check the following:
• Setting of Precharge/Discharge
Time (F.014)
• Precharge/Discharge Resistor,
and wiring to it
Check the following:
• Wiring for sequence signals
• Wiring to coil of main magnetic
contactor
• Order of phases of wiring for main
power supply and control power
NO
NO
NO
NO
RUN sequence
input entered?
Precharge is
completed?
Main
magnetic contactor
operate?
The unit is defective.
Replace the unit.