What can cause an OCF fault on the ATV312 (or ATV31) drives?

Issue:
The drive tripped on OCF code.

Product line:
Altivar 312, ATV312

Environment:
all

Cause:
OCF is an over current condition.  Load is mechanically blocked, or too large for the drive/motor.

Resolution:
Check the motor nameplate information and compare the amperage and HP rating to the drive part number/ratings.  Check the drive programming under the DRC menu (BFR, COS, NCR, UNS, NSP, UFT).  These values should match the motor nameplate.  Make sure the ITH parameter under the SET menu is adjusted to the motor FLA.  Also enable Catch on the Fly in the FLT menu, parameter FLR (change to yes).

Check the line voltage coming into the drive.  Less than nominal voltages may cause the current to run higher.

Make sure the load is running in the correct direction.  While the load is running, check the current draw either with a meter, or under the SUP menu and parameter LCR (motor current).  The current should not exceed the motor FLA.

The drive may also display an O.CF (indicates a phase to phase issue in motor or cable) or an OC.F (phase to ground problem in motor or cable)

Be sure to identify which fault code is displayed.

Released for:Schneider Electric South Africa