Inverter alarms are one of the most common reasons solar customers call their installer. Most are harmless and clear by themselves. Here are the codes customers see most, based on manufacturer guidance.
Solis
- NO-Grid (1015): the inverter can’t detect the grid. Check the AC breaker and whether there’s a power cut.
- OV-G-V (1010): grid voltage went above the limit. Occasional trips recover by themselves; frequent ones need checking.
- UN-G-V (1011): grid voltage dropped below the limit, usually a short grid dip.
- PV ISO-PRO (1033): low insulation resistance on the panel wiring, often on damp mornings. If it persists in dry weather, it needs a technician.
- OV-TEM (1032): the inverter is too hot. Check ventilation and direct sun.
GoodWe
- Utility Loss: no grid voltage. Check for a power cut and the AC breaker.
- Isolation Fault: panel insulation to earth is low, often after rain.
- Vac Fail / Fac Fail: grid voltage or frequency outside the range set for Ireland.
- PV Over Voltage: panel voltage is above the inverter’s input range. Needs a technician.
Tesla Powerwall
- Grid outage: Powerwall is running the home during a power cut. Reduce big loads.
- Powerwall overloaded: too much demand during an outage. It retries after about two minutes.
- Circuit breaker open: switch the Powerwall breaker back on.
- Side switch off: turn the switch back on if you didn’t switch it off.
Safety first
Customers should never open an inverter or touch DC isolators. Electrical checks must be done by a qualified electrician.
Answer these questions automatically
WattScribe answers inverter, battery and app questions for your customers 24/7 and passes anything safety-critical to your team. Try the error-code search.
