Issue:
My Smart UPS Modular Ultra shows one or more of the following alarms.
A671 – Power Module PFC Shutdown: High Positive DC – Hardware Circuit
A681 – Power Module PFC Shutdown: High Negative DC – Hardware Circuit
A691 – Power Module PFC Shutdown: High Positive DC – Firmware
A6A1 – Power Module PFC Shutdown: High Negative DC – Firmware
Product Line:
Smart UPS Modular Ultra
Environment:
All models, all serial numbers
Resolution:
Usually, the alarm is caused by one of these events below. The power modules are OK and should not be replaced.
If the alarm is caused by:
- An inductive load being applied, reduce the inductive load then clear alarms.
- The Service Bypass Unit (SBU) being switched from the "Normal" position to the "Maintenance" position, ensure the UPS is in Bypass by using the "Put UPS into Bypass" command on the display (Control > UPS > Put UPS into Bypass) prior to switching the SBU position.
- The output being miswired and another source is backfeeding into the UPS output, ensure the wiring is corrected.
To reset the alarm from the display menu go to Menu > Control > UPS > Clear Alarms. If you try and clear the alarm too quickly, the Power Module DC buses may not have enough time to discharge which would set the alarm again. Wait 3 minutes before performing the Clear Alarms action.
If the issue persists, please contact technical support.
Released for:Schneider Electric India
