Communication Timeout Error

What does 1508.5 mean?

This status bit, when active (1), indicates that the Serial Communication Unit (SCU) did not receive a response from the Destination Device within the expected time frame. This suggests either the Destination Device is not responding, is too slow to reply, or the response message is not reaching the SCU, causing the communication attempt to fail.

• The Destination Device (inverter) is not powered on or not properly communicating.
• Incorrect Destination node address configured in the CMND instruction (C+3 lower byte).
• The response timeout value in the CMND instruction operand (C+5) is set too short for the communication link or device processing time.
• Loose or damaged serial communication cable connections preventing response reception.

Click steps to track your progress.

1. 1

   Verify the Destination Device is powered ON and its Modbus slave address matches the CMND instruction's destination node address (C+3 lower byte).

2. 2

   Increase the Response timeout parameter C+5 (e.g., from #0000 (2s) to a higher value) in the CMND instruction operand to allow sufficient time for the Destination Device to respond.

3. 3

   Inspect the serial communication cable for continuity and secure connections at both the SCU and the Destination Device.

4. 4

   Monitor the Destination Device's status to confirm it is not in a busy or non-responsive state that would delay its replies.