Inverex Nitrox F13 — Grid Over-Voltage
What it means: Grid voltage exceeded the permitted window, so the inverter disconnected from the grid.
Why does Inverex show F13?
- Weak/fluctuating feeder voltage (common on Pakistani grids, especially evenings)
- Loose neutral connection
The Pakistan factor
The single most common nuisance error on weak feeders in Punjab; worse in summer evenings.
How to fix it (safe to try yourself)
- Measure grid voltage at the meter; if it exceeds 250V regularly, log times of day.
- Widen the grid-voltage window in settings ONLY within the permitted range.
- Report persistent overvoltage to your DISCO — it is their fault to fix, and it damages appliances too.