- Error code
- FS 81 – FS 83
- Category
- Grid overvoltage
- Manufacturer
- KACO
1What the error means
Over-voltage detected on one conductor. An internal protection mechanism disconnected the device to prevent damage. The three codes correspond to the three phases.
On the display or in the monitoring software it appears as FS 81 – FS 83.
2Possible causes
- High grid voltage at the point of connection
- Undersized or very long AC cable — the inverter raises the voltage while it feeds in
- Several inverters on the same line
- Wrong country setting
3What to do
- Measure the voltage at the point of connection while the inverter is feeding in.
- Check the cross-section and length of the AC cable.
- If the grid voltage is permanently high, notify the grid operator.
- If the voltage is normal and the fault persists, the inverter's measuring circuit needs to be checked.
Codes covered
This fault appears with the codes FS 81 – FS 83. The manufacturer documents them as a single fault — the number indicates the stage or the phase in which it was detected.
4Repair by Aineas
You send the inverter to our lab in Thessaloniki. We diagnose it, inform you of the fault and the cost, and the repair starts only after you approve it. Every inverter is tested under simulated operating conditions before delivery.