Warning /Alarm 46 in VLT FC301/ FC302 : Power Card Supply - comes when the supply on the power card is out of range. Another reason can be a defective heat sink fan.

There are 3 supplies generated by the switch mode supply (SMPS) on the power card:
- 24 V.
- 5 V.
- ±18 V.
When powered with VLT® 24 V DC Supply MCB 107, only 24 V and 5 V supplies are monitored. When powered with 3-phase mains voltage, all 3 supplies are monitored

1. Check for a defective power card.
2. Check for a defective control card.
3. Check for a defective option card.
4. If a 24 V DC supply is used, verify proper supply power.
5. Check for a defective heat sink fan.