I recently replaced my old 12V system (16 yo lead-acid batteries died). Kept my 5kw array of Uni-Solar flexible panels (they are a thin film panel that glues onto standing seam metal roofs. No mounts, no penetrations.) Installed 2 EX-6500 inverters in split phase and 6 EG4 48V 100Ah batteries. I followed al l the guidance, so there are breakers between the batteries and the inverters, PV combiner boxes creating 3 strings, DC Cutoffs between the PV Combiner boxes and the inverter MPPTs. The attached wiring diagram shows it all as best I can do. There is also a transfer switch to connect the generator as a source when the grid goes down.
AC IN power to the inverters is direct from one of the house's two main service panels. AC OUT serves a sub panel with critical loads.
All in connected and in service, functioning properly EXCEPT, I have flickering in certain lights in the house. The flickering varies with what loads are on, whether PV is connected or not, night versus day. But no condition eliminates the flicker. I'm guessing it is a grounding issue. These inverters are the latest (Feb '23) so I assume they do NOT have the ground/neutral bond screw installed. And they have the latest firmware, according to Signature Solar.
My grounding setup is all grounds joined at a local terminal block, then grounded back to the sub panel. There is no ground neutral bond in the subpanel, only in the main service panel. Since the wiring diagram was drawn, I have separated the DC and AC grounds, with DC ground direct to a house plumbing ground fixture. I also tried running separate ground wires from each inverter back to the sub-panel, but no change in the flickering. The flicker also appears in some circuits that are not powered (fluorescent lights).
I have been trying to get a response from Sig Solar for over a month. I can't get a return call and email responses are at least a week apart.
So does anyone here have any idea of how to resolve this issue, or at least something to diagnose it? Thank you.
AC IN power to the inverters is direct from one of the house's two main service panels. AC OUT serves a sub panel with critical loads.
All in connected and in service, functioning properly EXCEPT, I have flickering in certain lights in the house. The flickering varies with what loads are on, whether PV is connected or not, night versus day. But no condition eliminates the flicker. I'm guessing it is a grounding issue. These inverters are the latest (Feb '23) so I assume they do NOT have the ground/neutral bond screw installed. And they have the latest firmware, according to Signature Solar.
My grounding setup is all grounds joined at a local terminal block, then grounded back to the sub panel. There is no ground neutral bond in the subpanel, only in the main service panel. Since the wiring diagram was drawn, I have separated the DC and AC grounds, with DC ground direct to a house plumbing ground fixture. I also tried running separate ground wires from each inverter back to the sub-panel, but no change in the flickering. The flicker also appears in some circuits that are not powered (fluorescent lights).
I have been trying to get a response from Sig Solar for over a month. I can't get a return call and email responses are at least a week apart.
So does anyone here have any idea of how to resolve this issue, or at least something to diagnose it? Thank you.