Siemens SINAMICS PERFECT HARMONY GH180 - Page 450

Fault display Type Enable Potential causes and corrective actions
PreChrg Contactor Alarm A Cause
During pre-charge, if any pre-charge contactor (M2, M3, and M4) does not
respond as directed, this alarm is issued along with a pre-charge fault.
After pre-charge completes, the command to the pre-charge contactor
(M2, M3, and M4) is compared to feedback (acknowledge) and if they do
not agree, an alarm is issued.
Possible causes include:
• No power to contactor coils.
• Incorrect wiring of contactors and auxiliary contacts.
• Defective user I/O module 1.
• Loose or defective 󹪝ber optic cable between DCR and NXGpro user I/O
module.
Action
1. Check for control power to contactors.
2. Check wiring; check connections to user I/O module 1.
3. Check 󹪝ber optic cable connection between DCR and NXGpro user I/O
module.
4. Replace user I/O module.
5. Replace DCR.
PreChrg Breaker Opened A Cause
This alarm indicates that the pre-charge breaker was commanded to open
when the precharge contactors M2, M3, or M4 failed to open. This alarm
is applicable to only pre-charge Type 5 or Type 6.
Possible causes include:
• Incorrect wiring from user I/O module 1 to the pre-charge contactors.
• The user I/O module is broken, which results in reporting incorrect
status of the contactors.
• Incorrect attenuation resistor values for required input voltage.
Action
1. Check pre-charge contactors and auxiliary contacts.
2. Replace user I/O module.
3. Evaluate wiring.
4. Check input protection fault and correct.
Troubleshooting Faults and Alarms
11.4 Drive Faults and Alarms Input Line Disturbance
NXGPro+ Control Manual
448 Operating Manual, A5E50491925A