I respectfully request your expertise.
So here is the scenario:
Renogy 2000W inverter
Renogy 100w solar x2
Interstate batteries x2 (I have not been able to sort out Amp hours yet...but willing to take advice. They are not the final solution, but they are what I have now.)
Solar works, Batteries charge and discharge, inverter runs shop vac, chop saw, heavy duty blower...with an extension cord (so I don't think it's the inverter...maybe).
When I use a generator to the circuit breaker box, all outlets in the bus work (120v).
When I plug the circuit breaker box into the inverter, all I get is a ground fault (light and unit shuts down).
All outlets test correct when using the plug-in outlet tester (similar to this one)
I've tried using the separate grounding screw on the inverter to the circuit breaker box, to the 12v fuse block, to the common ground (bus chassis) for the batteries (all three, two of the three, and each individually). I've used different wire gauges 12, 10, 6 and 4. (Only the extra ground. Not the main ground, which is 2.)
I can plug in the circuit breaker box, flip one circuit (#2)(the only one with 1 outlet) and no problems until I plug in something to the outlet (a power strip with nothing else plugged in...so I can see the light and have a switch to turn on/off to test. Only fails when power strip is turned on).
If I flip any of the other circuits, I get a GF error.
One circuit (#1 - 4 outlets, no load) has GFCI outlets (2) (yes, I know, I only needed one, but I had it and it worked.)
The second circuit (#3- 3 outlets, no load) none are GFCI.
I swapped circuit breakers in the box (moved to another position in the box) with no noticeable differences...so I switched them back so my diagram is correct.
I've talked(been on hold) with Renogy, and I've received hours (5+) of waiting, talking, then being put on hold, disconnected, and/or getting the "I dunno, just send it in."(but never further instructions from customer service).
Oh...and I used red, black, and white wires...but that surely has no effect, right?
ANY suggestions or recommendations to check/inspect/solve?