Wiring an inverter- 1/0 inside or out?

Close to wrapping up my Hellroaring dual battery install in our 97. I'll be running a 2kw/4kw inverter in the rear cargo area to power a small microwave. I plan to run 1/0 welding lead, fused w/ a 250A ANL fuse block in the engine bay. With the HellRoaring isolator/combiner I chose, all loads should be run off the primary battery which is on the US driver side.

So, should I run the cable outside the truck along the frame rail, crossing to the passenger side in the engine bay? To do this I'll need to cut 1 ~2" hole or 2 ~ 1" holes in the floor near where I'll mount the inverter.
Another option would be to run the supply cable through the firewall and inside the cabin. Anyone done this? Any good "channels" to recess the cable in?

I also plan to ground the inverter to the frame. Since the main battery large ground runs to the block, is the frame sufficiently connected to the engine to conduct 250A? How, thru the tranny crossmember? Should I run another ground using 1/0 from the battery to the frame?

Cube Dweller said:

C is the frame sufficiently connected to the engine to conduct 250A?

Click to expand...

no. there are a few small jumpers from the frame to the engine on the drivers side of the engine but otherwise the engine sits in rubber at all three points.

I grounded my aux battery to the frame and then from the frame to the block, the main battery grounds to the block at the same place the stock battery wires did.

there is a wiring channell along the door sill, pull the step tread from the bottom of the door opening and you will see,

you cna pass through the firewall at the dead cluctch master plug

RavenTai said:

there is a wiring channell along the door sill, pull the step tread from the bottom of the door opening and you will see,

you cna pass through the firewall at the dead cluctch master plug

Click to expand...

Yeah... but it's not nearly big enough for the copper hose he's talking about here, is it? I've used that raceway for smaller wires, but remember it as a signal path only... no real juice.

I've heard that you should run the negative of the inverter back to the battery. There are a few posts in other threads about that. My directions for mine told me to. I ran 1/0 gaurge under the carpet because it was too thick to run though the channel in the door sills. With the floor matts to add a little thickness I can't feel the wire running under the carpet.