chassis grounding of house batteries and AC???

[bevans6]

I'm installing the house 12 volt wiring and I'm running every load with a dedicated wired ground return.  It's my belief that this will be a better way to go than using chassis grounds as the return.  First question is - is the actually so?  Second, since I'm not using the chassis for anything, is there a reason to, or to not, ground the house batteries to the chassis?  Normally I would as a matter of course, but now I'm thinking too much...

Now for AC.  I do not have AC neutral bonded to ground anywhere in the coach.  Neither have I yet bonded AC ground to the chassis.  Should I bond AC ground to the chassis, or should I not?

Thanks very much.

Brian

[Len Silva]

Clearly, yes. Both the AC ground as well as every AC appliance and the batteries should be bonded to the chassis.

[bevans6]

That's what I would expect, actually.  As I said, I was over-thinking things....

But Len, you imply that AC appliances should be separately grounded to the chassis, as well as through the panel.  I wouldn't think that multiple ground paths for AC would be a good idea.  I currently have all AC outlets tied back to the ground buss in the AC distribution panel.  The appliances would find their path to ground there, is that not correct?

Thank you very much for your advice, I appreciate it.

Brian

[Len Silva]

I overcomplicated it myself. Plug in appliances are bonded through the ground wire.  The generator, inverter, and of course, the main distribution panel should be bonded to the chassis.

[Sean]

Brian,

Your are required to bond the battery negative to the chassis.  You are also required to bond the AC panel ground to the chassis with a minimum #8 wire (unless the panel itself is constructed such that the ground bus is bolted directly to the chassis).  Same goes for the generator and inverter, if any.

Grounds should always be permanently connected, never switched.  The AC neutral should be isolated from the ground in the panel, but connected to it in the generator and inverter.  These neutrals should be disconnected from the panel when on shore power, necessitating neutral-switching transfer gear.

Cord-and-plug connected appliances are generally grounded only through their cords and then to the panel ground.  Hard-wired permanent appliances may additionally be grounded to the chassis -- consult the appliance's installation manual.

-Sean
http://ourodyssey.blogspot.com

[bevans6]

Sean and Len - thank you very much.

Brian