F109-150
Difference level RS485 driver. Fault Faulty "B" or "Cycle" signal
SEW Eurodrive · MOVIDRIVE MDX60B/61B Variable Speed Drive
What does F109-150 mean?
A fault is detected in the RS485 driver, specifically with the 'B' or 'Cycle' signal. This is usually caused by no encoder connection or an incorrect encoder type being connected.
Common Causes
- RS485 communication line issue between driver and controller.
- Faulty 'B' or 'Cycle' signal wire integrity.
- Incorrect RS485 termination resistors.
- Noise interference on the RS485 data lines.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Check encoder connection.
- 2
Check encoder cabling.
Verified technical data. Last updated: March 2026
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Source: SEW Eurodrive MOVIDRIVE MDX60B/61B Variable Speed Drive