Chassis Grounding Question

[zacherrie]

Hi All,

I have a question regarding grounding to the chassis. I looked through the available Resources here and couldn't find anything that related to my (unique?) situation.

Long story short. I am using one of the GFCI outlets on my camper to run a AC to DC charger for when I'm hooked up to shore power.

My question is, do I need to ground to the chassis at my negative buss bar? Or would that create a grounding loop since the Ac to DC charger, plugged in at the GFCI outlet is routed to the camper included converter/fuse/breaker box, which is grounded to the chassis at that point?

Below is a simplified version of my situation (I removed some aspects such as solar, SCC, ect) to simplify my setup to the relevant components.

Thanks for your help all.

 

[HRTKD]

I removed my AC-DC charger a few months ago. I don't believe that it was connected to a GFI outlet, nor are there any GFI breakers in my main distribution panel

 

[zacherrie]

I removed my AC-DC charger a few months ago. I don't believe that it was connected to a GFI outlet, nor are there any GFI breakers in my main distribution panel

Thanks HRTKD. There is a breaker for the outlet at the WFCO device and the outlet provides power when shore power is engaged. Valid ground with that in mind? Both if hooked up to shore and if boondocking? I don’t have any inverter for my boondocking system, just the dc fuse box and WFCO included box shown in the diagram

 

[Ep1phany]

This post should explain it all: https://diysolarforum.com/resources/grounding-made-simpler-part-4-mobile-systems.159/
Link to download the document is at the top right.

 

[HRTKD]

There is a breaker for the outlet at the WFCO device and the outlet provides power when shore power is engaged. Valid ground with that in mind? Both if hooked up to shore and if boondocking?

Shore power will be properly grounded and bonded at or upstream of the pedestal. The generator may or may not have the n-g bond.

 

[TacomaJoe]

Your system will work as shown as long as all the negatives for your self installed DC plugs are connected to the buss bar. Your battery system is isolated from the converter 12V system meaning that you won't have 12V between the battery positive and the frame unless the buss bar is tied to the chassis. The AC/DC charger should not provide a negative return for the battery system.

 

[zacherrie]

Your system will work as shown as long as all the negatives for your self installed DC plugs are connected to the buss bar. Your battery system is isolated from the converter 12V system meaning that you won't have 12V between the battery positive and the frame unless the buss bar is tied to the chassis. The AC/DC charger should not provide a negative return for the battery system.

Thanks TacomaJoe. I was going to have all of the DC negatives attach at the fuse box and have the negative for the fuse box attached at the negative bus bar. I'm having trouble following your second and third sentences. If the battery system is isolated from the converter and the AC/DC system should not provide a negative return for the battery system, does that mean I should have a grounding wire going from the negative bus bar to chassis for my system?

 

[TacomaJoe]

Think of it like this. You have the vehicle system, and then you set a battery next to the vehicle. Plug the charger into the vehicle and the battery charges but if you connect a light bulb between the battery positive post and the vehicle chassis, it won't light because there is no return path. The negative post of the battery on the ground needs a connection to the vehicle chassis to complete the path.

 

[0truck0]

Someone posted this before...
There is no right answer, answers are difficult, but you are correct that you do not want a ground loop, ground once.
See https://diysolarforum.com/resources/grounding-made-simpler-part-4-mobile-systems.159/
.Grounding info

 

[zacherrie]

Thanks all. Might have to do some testing and wire re routing but this gives me a great place to start