Cause : Main contactor Fault comes when control program does not receive main contactor on (1) acknowledgement through digital input even control program has closed the contactor control circuit with relay output.

Main contactor / main breaker is not functioning properly, or there is a loose / bad connection.

1. Check main contactor / main breaker control circuit wiring.
2. Check the status of other switches connected to contactor control circuit.
3. See the delivery-specific circuit diagrams.
4. Check main contactor operating voltage level (should be 230 V).
5. Check digital input DI3 connections.