Grid voltage relay fault

What does 457 mean?

This code indicates a fault with the internal grid voltage relay. This relay is essential for connecting and disconnecting the inverter from the grid, and its malfunction prevents the inverter from feeding any energy.

• Mechanical failure of the grid voltage relay contacts.
• Control circuit fault for the relay.
• Damage or improper connection of the AC cable to the inverter.

Click steps to track your progress.

1. 1

   Check the AC cable connections to the inverter for any damage or looseness.

2. 2

   If the error persists after confirming the AC cable, notify a Fronius-trained service engineer for relay diagnosis and potential replacement.

3. 3

   Perform an AC reset to attempt to clear any transient relay control issues.