Fault Reasons：Inverter will show “Mains Lost” when the AC grid disconnected.
Troubleshooting：
1. Check if the mains(power grid) is working normal, please enter the next step if it is；
2. Check if the AC breaker or other protection switches are turned off, please enter the next step if it isn’t；
3. Check the L, N and PE cables which are connected in the inverter AC terminal are in the same sequence with the marks on it；
4. Use a multimeter to measure whether the voltage between L and N wire of the mains(power grid) at the inverter output terminal is around 230V, the mains is abnormal if it isn’t；
5. Check if the AC breaker, knife-switch, overvoltage protector or other safety protectors are working properly；
6. Please contact sunways after-sales team at service@sunways-tech.com or +86 400 9922 958 if all steps above have been checked and excluded.