raj_pm is on the money with the counterbalance check. We had the exact same 3281 on an ACS880 driving a 200T Komatsu and wasted two days looking at drive parameters before someone thought to check the counterbalance gauge. Pressure had dropped from 4.2 bar to 2.8 bar overnight — slow leak in a fitting.
But if your counterbalance checks out, here is the diagnostic sequence I follow for 3281:
1. Check motor cable connections at both ends. A loose power cable creates intermittent stall faults that look random. Especially the drive-side terminal — vibration loosens them over time.
2. Pull up parameter 01.10 (motor current) in the drive log and look at what was happening right before the fault. If current spiked to limit before the stall, it is mechanical. If current was normal and the drive just lost position feedback, it is more likely an encoder issue masquerading as a stall.
3. On the ACS880 specifically, check parameter 99.04 for the fault timestamp and 99.06 for motor speed at fault. If speed was near zero (within 5 rpm of standstill), the motor never started moving — that points to a jam or brake not releasing. If speed was mid-stroke, something grabbed it during motion.
One more thing: if this press has been running for years without 3281 and it suddenly appears with no changes, check your incoming power. We had a phase imbalance from a utility issue cause intermittent stalls on two presses simultaneously. Took us a while to connect those dots.