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## Fault 3281 Definition
ABB ACS880 fault 3281 is motor stall — the drive has detected that the motor is not rotating despite being commanded to move. On a servo press, this typically means a mechanical jam or severe overload.
## Immediate Safety Check
Before any diagnosis: verify the press slide is not stuck in a position that could cause injury when released. If the slide is stuck mid-stroke with a die loaded, call a qualified press technician.
## Diagnosis
### Check for Mechanical Jam
- Inspect die area for foreign objects
- Check if slide moves freely by hand (with drive disabled and counterbalance air on)
- Check gib clearance — if gibs are too tight, slide can jam under load
### Check Drive Parameters
Fault 3281 is triggered when motor speed stays below parameter 25.11 (stall speed limit) for longer than parameter 25.12 (stall time limit).
Default values: 25.11 = 5% of rated speed, 25.12 = 20 seconds.
For a servo press with slow forming strokes, 5% of rated speed may be too close to normal forming speed. Check if the forming speed is above 25.11.
### Check Motor Feedback
If the encoder cable is damaged, the drive receives no speed feedback and assumes stall. Check encoder cable continuity and connector condition.
### Check Load
If the press is forming material that is significantly harder or thicker than designed, the motor may genuinely stall. Check material certificate against die design spec.
## Reset
Fix mechanical issue first. Then: fault reset via ACS880 control panel or fieldbus command.