The device distinguishes two things: the target state – your command – and the actual state, the hardware feedback. The two can differ, because a safety circuit or the protective logic of a channel board can drop the contactor regardless of the command. The symbol shows both at once so that such a discrepancy is immediately visible.

If the state cannot be determined at all because of a communication error, a red exclamation mark appears. This points to a hardware defect – please contact customer service.

Which symbol shows which state, with its shape and colour, is listed in the table in Section 7.3, “Main contactor ON/OFF”. There the main contactor dialog also shows command and feedback separately, together with the enable of each board.