Faults and alarms¶
The ACH550 surfaces problems as faults (the drive trips and refuses to run) and alarms (the drive continues running but warns of an abnormal condition). Codes appear on the keypad and as bits in the Status Word.
Reading a fault¶
When the drive is tripped:
- The keypad shows the fault code (e.g.
F0001 OVERCURRENT) and the description. - The Status Word bit
TRIPPED(bit 3) is set. - The drive will not accept a start command until the fault is cleared.
Clearing a fault¶
- Identify and address the underlying cause. Do not repeatedly reset a fault without understanding it; that masks the warning until it becomes a hardware failure.
- From the keypad, press
RESET. The fault clears if the underlying condition is no longer present. - From software, the Control Word reset bit (bit 7) clears the fault. ADCL WinSoft does not currently expose this as a UI button; clear from the keypad.
Common faults¶
| Code | Meaning | Likely cause |
|---|---|---|
F0001 OVERCURRENT |
Drive output current exceeded its trip limit | Test section blockage, sudden mechanical resistance, very short acceleration ramp at high load. |
F0002 DC OVERVOLTAGE |
DC link voltage too high | Regenerative load on a fast deceleration; lengthen 22.02 DECEL TIME or add a braking chopper. |
F0003 DEV TEMP |
Drive over temperature | Cabinet ventilation blocked or cooling fan failed. Open the cabinet (after the 5-min wait) and inspect. |
F0006 EARTH FAULT |
Imbalanced output currents | Motor or cabling insulation issue. Stop using the drive and inspect with a megger before resuming. |
F0010 PANEL LOSS |
Keypad disconnected while in LOC mode |
Reseat the keypad or switch to REM. |
F0028 SERIAL 1 ERR / similar |
Fieldbus communication lost while the drive was being controlled remotely | Modbus connection dropped; see Modbus connection. |
The full fault list is in the ABB ACH550 User's Manual, which lives under docs/reference/abb/ (file not yet committed; pull it from the ABB website if you need the exhaustive list).
Common alarms¶
| Indicator | Meaning |
|---|---|
ALARM bit (bit 7) set in SW |
A non-fatal warning is active; the drive continues to run. |
Keypad shows Auut / Auxx text |
Auto-tuning or auxiliary mode hints from the drive; usually informational. |
ABOVE bit (bit 10) set in SW |
The drive is operating above its commanded speed (overshoot during rapid acceleration). |
Alarms do not require operator action but should be noted in the run log if they appear unexpectedly.
Repeating faults¶
If a fault repeats within minutes of being cleared, stop running. The pattern is either a hardware problem (overheating, blocked airflow, mechanical resistance) or a software bug producing bad commands. Investigate before re-energizing.
For repeating faults, the diagnostic flow is:
- Document the fault: code, time, drive parameters at the time of the trip (some are stored in fault history).
- Reproduce the conditions if possible at a low-load setpoint.
- Open a
WT_MS_<n>/debug_session.mdand capture everything. - Only resume routine operation once root cause is identified.
Drive history at the keypad¶
The keypad has a fault history menu — MENU → DRIVE HISTORY. The last several faults are stored with timestamps. This is useful when an operator reports "the drive tripped during my last run but I cleared it and went home" — the history is the only record.