43
Communication timeout (RS485 cyclical)
SEW Eurodrive · Drives
What does 43 mean?
A communication timeout occurred during cyclical communication via RS485. This results in the drive decelerating and stopping along its set ramp, indicating a disruption in the continuous data exchange.
Common Causes
- Interrupted or faulty communication link between the RS485 master and the MOVIMOT® inverter.
- Too many MOVIMOT® inverters (slaves) connected to the RS485 master for cyclical communication, causing the communication cycle to exceed the configured timeout interval (e.g., more than 8 drives for a 1-second timeout).
Repair Steps & Checklist
Click steps to track your progress.
- 1
Check and re-establish the communication link between the RS485 master and the MOVIMOT® inverter, verifying RS+ and RS- terminal connections.
- 2
Check the number of slaves connected to the RS485 master. If the MOVIMOT® inverter's timeout is set to 1 s, ensure a maximum of 8 MOVIMOT® inverters (slaves) are connected for cyclical communication to prevent timeouts.
- 3
Reduce the message cycle time or increase the timeout interval if allowed by the application and master settings.
Verified technical data. Last updated: March 2026
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Source: SEW Eurodrive Drives