F13 — grid abnormal / won't reconnect

F13 means the inverter sees the grid as outside its allowed window and won’t (or won’t stay) connected. Two broad causes:

A. Grid code / region set wrong (most common at commissioning)

If the inverter was never set to the correct standard, a healthy grid can still look “abnormal”.

1. Confirm the safety standard is AS/NZS 4777.2 and the region matches the DNSP.
2. Recheck any export-limit and protection settings against the connection approval.

B. Genuine grid condition

If the code is correct, the grid really is out of spec at that moment.

1. Measure grid voltage and frequency at the inverter AC terminals. High voltage at the end of a long street is a common AU cause.
2. Check the AC connection — loose neutral/active, undersized cable, or a tripped upstream breaker.
3. The inverter auto-reconnects once the grid returns to spec for the standard’s reconnect time.

Persistent over-voltage trips usually need the DNSP involved (tap change / supply issue), or a cabling fix — not an inverter setting. Document the readings before escalating.