When I read 250.4(A) it makes me wonder why we would ground a truly "portable" generator at all. What is the function of the ground or a main bonding jumper on a portable generator? It looks like you are simply adding a dangerous fault path that has no real good reason to even be there. I understand once you connect this to a structure it becomes a separately derived system or it uses the building grounding and MBJ (depending on your transfer equipment) and those rules change but if I am sitting at a camp site in the woods or prairie building away from PoCo power, what does grounding the generator or bonding the neutral accomplish?
Flame away.
(A) Grounded Systems.(1) Electrical System Grounding.Electrical systems that are grounded shall be connected to earth in a manner that will limit the voltage imposed by lightning, line surges, or unintentional contact with higher-voltage lines and that will stabilize the voltage to earth during normal operation
