Issue:
His ATV320 drives  trip on OSF faults, after replacing the ATV312 drives, that did not trip on OSF.

Product Line:
ATV312 and ATV320

Environment:
All

Cause:
The DC bus OSF fault threshold has changed.

Resolution:
The DC bus OSF fault threshold changed from 840vdc on the ATV312 drive to 790vdc on the ATV320 drives.
-             To check if URES is set to 500V  [GO to DRI- > CONF > FULL > FLT- > DCC- >> Look for URES]
-             To monitor the line supply voltage, check if the input voltage is in accordance with the drive rated supply voltage (380...500 V (- 15...10 %)

UNS [Motor Rated Voltage] isn’t linked to the OSF [Main Overvoltage] trip threshold.
However, URES [Main Voltage] has an influence on OSF trip threshold. Indeed, depending of the setting of URES, trip threshold will be different.

For the ATV320, with URES sets to 500V, OSF trip threshold is 790V.
For the ATV312, with URES sets to 500V, OSF trip threshold is 840V.

Released for: Schneider Electric Saudi Arabia