Re: Inverter grounding
Not a problem--I try to explain what the theory is behind the issues (such as grounding) so you can make the best decision for your installation as it is difficult for me to do that from X,XXX miles away behind a keyboard.
Regarding DC (and AC too) Grounding. You want to make sure you have only one ground connection per "circuit" so that you don't get parallel current paths (example, grounding the DC "-" at the solar panel and again grounding the Battery Bus "-" terminal). You can get parallel current flow (or lightning induced current surges) when there are multiple paths (another common multi-path ground is when you have the battery grounded and running a car or HAM radio from 12 VDC--The case is DC ground and Safety Ground, and so is the Antenna braid ground too--Running a DC ground to the radio chassis plus a safety green wire to the antenna braid ground can create such a loop).
Regarding the solar panel ground--I am assuming that you are Earth Grounding the solar panel aluminum frame... and NOT Grounding the "-" wire from the solar array anywhere. Correct?
20x BP 4175B panels (replacement) + Xantrex GT 3.3 inverter for 3kW Grid Tied system + Honda eu2000i Inverter/Generator for emergency backup.