Replace a positive ground, Sunpower SPR-7000 to a transformer-less inverter

[frankdp23]

I see this is an older thread. But I was having some similar kind of issues (now for 2.5 years). My system is from 2011 and it needed 2 new inverters that after fighting Sunpower did replace. They were SPR 7000s. I had an outside guy come look, and it turns out when they installed the 2 new inverters, they grounded them neg instead of positive. So they were generating a lot less kwh. The guy fixed it now to positive, so hopefully that helps the productivity. I was only getting about 55% of what I should.

This fixed my issue. Yesterday and the prior sunny days I was back to producing 90-92 kWh per day instead of the 50 or less I was producing prior to this fix.