This included PDF associated with an POWER INVERTER describes the requirement for grounding the CHASSIS as well as the DC RETURN cables to be compliant with the NEC.
Perhaps your POWER INVERTER MANUAL does not go into much detail as listed in this specific PDF...
Read POWER INVERTER Install procedure section...
I have separately grounded both my POWER INVERTER Chassis connections as well as my CONVERTER Chassis connections in my installations to meet the safety requirements of the specific NEC regulations.
The NEC added requirements to me is because the POWER INVERTERs, CONVERTER/CHARGERs as well as SOLAR POWER SYSTEMs all fall under ALTERNATE POWER SOURCES. Its an effort to make things safe to use when things fail...
There are also safety regulations telling us not to stand under a tree during heavy lightning storms. I don't question those safety regulations as well to save a few dollars. This is well above my paygrade to be questioning things...
Roy Ken
