CMND Instruction Destination Node Error / Response Timeout

What does 02-05 mean?

This error indicates that the CMND instruction failed due to a problem communicating with the destination node, specifically a response timeout. This means the destination device (e.g., inverter) did not respond within the configured timeout period, preventing the CMND instruction from completing successfully.

• The destination device (inverter) is not powered on or improperly connected to the serial communication unit (SCU).
• Incorrect serial communication settings (baud rate, parity, stop bits) on the SCU or destination device.
• The destination node address in CMND instruction operand C+3 (lower byte) does not match the actual address of the inverter.
• Communication cable issues (broken wire, incorrect wiring, excessive length).
• Response timeout parameter C+5 is set too low for the network conditions or destination device processing time.

Click steps to track your progress.

1. 1

   Verify power supply to the Destination Device (inverter) and check physical serial communication cable connections at the SCU and inverter terminals.

2. 2

   Check serial communication settings (baud rate, parity, data bits, stop bits) on the SCU and Destination Device, ensuring they are identical.

3. 3

   Verify the Destination node address in CMND instruction operand C+3 (lower byte) matches the inverter's configured Modbus slave address.

4. 4

   Increase the Response timeout parameter C+5 (4-digit hex) if the network or device processing is slow. The default value is #0000 (2s).

5. 5

   Inspect the serial communication cable for continuity and proper shielding to prevent signal loss.