another grounding question

Re: another grounding question

Hmmm, a difficult question to answer.

What kind/model/size of genset do you have? Typically, generators larger than ~3.5kW or so have the AC neutral grounded to the frame of the generator.

Usually, the correct way to connect such a genset (as backup behind a transfer switch to utility panel) would be to lift the neutral to frame ground at the genset and let the AC main panel ground to earth ground be the "one ground bond" point.

And then attach the genset frame to the same ground rod used by the AC panel.

Secondly, I would consider tying a 6 awg wire from the DC ground rod to the AC ground rod. I do not like floating ground between to power systems in the same home. In most cases, having the DC and AC grounds bonded together at one point is safer and better.

If your DC grounded equipment and your AC grounded equipment is not intermixed--then you could let the DC ground float wrt the AC ground.

In any case, the genset earth ground wire should go back to AC ground rod for safety (just run the green wire with the rest of the Hot/Neutral/Hot wiring).

This thread has a very nice (long) discussion about proper generator grounding.