System Configuration Fault

What does F66 mean?

This Automatic Fault indicates incorrect multi-unit configuration settings, such as more than one primary unit or non-unique device numbers in a multi-inverter setup. This prevents proper system synchronization and operation.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Ensure each unit has a unique Device Number.

2. 4

   Verify Inverter Mode and Connections have been configured correctly.