Warning /Alarm 4 in VLT Micro Drive FC301/ FC302 : Mains phase loss - A phase is missing on the supply side, or the mains voltage imbalance is too high. This message also appears for a fault in the input rectifier.

1. Options are programmed in parameter 14-12 Function at Mains Imbalance.

2. Check the supply voltage and supply currents to the drive.