I have a fully offgrid system powered primarily by a Growatt SPF-DVM 4000T. The system powers a large site with multiple cabins on the AC side. The inverter unit is located directly next to the panels with a buried grounding electrode. All solar panels and equipment housings are bonded and there is a Clamper 40kA 150V SPD on the DC side of the inverter.
There are multiple cabins connected to the inverter in a daisy chain configuration, the furthest being just over 100m away. I have a friend in the area who recently had his Growatt inverter destroyed by a lightning strike which struck a cabin (we live in the tropics and rainy season can mean a lot of heavy electrical storms) on his AC side, so I am figuring out the best way to put a SPD on the AC side. Is it best to have all the cabins EGC run the whole distance back to the inverter and to a DPS in the main AC panel? Or would a better design be to put a second grounding electrode at the furthest cabin? If that is the case then the SPD is still likely best placed directly next to the inverter? In the event of a lightning strike would a voltage build up between the two electrodes and damage devices in the cabins?
Thanks
There are multiple cabins connected to the inverter in a daisy chain configuration, the furthest being just over 100m away. I have a friend in the area who recently had his Growatt inverter destroyed by a lightning strike which struck a cabin (we live in the tropics and rainy season can mean a lot of heavy electrical storms) on his AC side, so I am figuring out the best way to put a SPD on the AC side. Is it best to have all the cabins EGC run the whole distance back to the inverter and to a DPS in the main AC panel? Or would a better design be to put a second grounding electrode at the furthest cabin? If that is the case then the SPD is still likely best placed directly next to the inverter? In the event of a lightning strike would a voltage build up between the two electrodes and damage devices in the cabins?
Thanks