Task overload
ABB · ACS880
What does 6481 mean?
An internal fault where the drive's processor is experiencing an overload of its internal tasks. This indicates a critical condition where the drive cannot maintain its real-time operations and cannot be reset normally. Continued operation is impossible and typically points to a fundamental software or hardware issue.
Common Causes
- Excessive number of active control tasks or background processes configured (e.g., multiple PIDs, complex motion profiles).
- High frequency of I/O updates or fieldbus data exchange rates (e.g., update time set below 10ms for Profinet).
- Processor-intensive custom application code running on the drive.
- Degradation of the internal clock source or CPU core frequency.
- Memory corruption leading to inefficient task scheduling and execution.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Reduce the configured fieldbus update rate (e.g., increase parameter P5-04 from 5ms to 20ms).
- 2
Deactivate non-essential background tasks or monitoring functions (e.g., diagnostic logs, trace functions).
- 3
Simplify complex control logic or reduce the number of active PID controllers (e.g., if multiple loops are running).
- 4
Monitor the processor load indicator (e.g., parameter P1-50 or P1-51) to identify peak usage.
- 5
Update the drive firmware to the latest stable version, which may include performance optimizations.
- 6
Perform a power cycle of the drive by disconnecting input power for 60 seconds.