Grounding

[christine]

I'm about to wire up my electrical system, and I think I've got most of it figured out, but the one subject that I can't seem to wrap my head around is grounding. Can anyone shed some light on the following:

1. Why is it necessary to ground a 12v system? I've heard that some people connect the negative battery terminal to the frame, and then connect the negative from all loads to the frame to save on wiring costs. If one intends not to do this, opting instead to use actual wire to connect back to the battery, is it still necessary to have a wire from the negative battery terminal going to the the frame, and if so, why?

2. Is it necessary to ground a 2000 watt DC-AC inverter? The inverter has a ground port ... what purpose does grounding it serve, what do I connect it to?

3. Is it necessary to ground the charge controller? The tristar controller has a ground port, but again I'm not really sure what it's for, or where to attach it.

Thank you in advance!

 

[sparky1]

ONLY DC Negative goes to the Frame of a vehicle.

"Yes" your Inverter which has a grounding point connection.

NEVER put any part of AC voltage to the frame..

 

[akrvbob]

i agree totally with sparky1. Ground the negative from the house battery to the frame!! Nearly all big inverters have the normal Positive and Negative posts and then a third, smaller post that is a ground to the frame. Be sure to ground it as well.

A good thing to do is set up a ground Block. It is grounded to the frame and has many posts to ground your items to it directly. Mount it to the wall and then all the devices you add are grounded to it--and then from it directly to the frame. This prevents your battery negative post from being a huge mess of wires.

you can do the same thing with a fuse block from the positve post of the battery and for the same reason

Use a BIG wire for the ground from the house battery to the frame, probably a 2/0 (2 ought). Depending on the number of fuses on the blocks and the size of your devices a 4 guage may be big enough for them.
Bob

 

[christine]

Got it, thank you both! Great idea for a grounding block. I think I'll do that.