Grounding Clarification of Panel for EG4 6500EX Inverters

[Henderson]

Hi, I've seen the below excerpt in the EG4 6500EX inverter manuals and have a basic question that I need some clarity on. When EG4 says not to ground panels, are they referring to grounding the metal case of the panel or the -ve terminal of the panel?

 

[timselectric]

Negative conductor.

 

[Henderson]

Negative conductor.

Ahhh, figured so but wanted to make sure. Thanks.

 

[Adam De Lay]

Ahhh, figured so but wanted to make sure. Thanks.

It's good to ask, cause the manual isn't very clear.