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Discussion Starter #1
I’m about to run 4 awg wire from the van battery to the house battery bank, which will sit next to the passenger side wheel well. I’ll be running it under the plywood floor. Which path is easier / favored:

Path A: Under hand brake, punch through step wall, 90 degree over to passenger slider, then rearward.

Path B: Through channel in front of passenger seat, down into passenger step well, punch through step wall, straight rearward.

Or is it a horse apiece?

Thanks
 

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I was tearing into my electrical just the other day and will also be placing my batteries in the space between the pass rear wheel well and behind the slider.
Measuring from the stepdown from the cab to cargo area, I'm at a minimum of 22' to get to the batteries, if I go up and over through the ribs, whether I go over the slider, or up the driver side and through a roof rib. Probably more like 25' when all done, plus the distance from the step to the battery.
I'm looking at more like 8' if I just come off the battery and through the floor, right over to the house battery.
My wires are 2ga and a hair under 1/2" diameter. Also, my floor sandwich is 1/2" polyiso, 1/2" ply, then the heavy plastic 1/4" factory cargo mat.
I'm thinking of bumping up to 5/8 (19/32) plywood and routing a channel for the 2ga. then cover with the cargo mat, which it pretty tough. More plastic than rubber. I'm also not fastening the mat to the plywood and will cut it to fit inside the finished cabinets. That way I can remove it if necessary.
I thought about running the wiring in the floor insulation, but then it would be buried forever and I would have to remove all the cabinets and plywood flooring to ever get to it.
Not sure what your specifics are, but maybe that will give you a few ideas.
I'm going today to get plywood and few other things since after Sunday, the state is shutting everything down.
I'll be working on the van as weather permits and I'll snap a few pics as I go. Hopefully it helps someone.
Counting me.
 

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Discussion Starter #4
Well, I went with Path A, like many have. RV8R’s build thread was helpful. The process was pretty easy.

I will be installing 1” rigid foam board (would have preferred 1/2”, but can’t find it here), 3/4 plywood, and Marmoleum. MsNomer’s posts about Marmoleum were helpful, and I’ve already ordered, received, glued-down, and trimmed it. No seams, durable, and looks great. Very happy with the floor so far. The plywood is lap-jointed by 1.25” so it moves as a monolith, making it quite heavy.

I have mounted two runs of Pex across the bottom of the plywood to feed a sink / outdoor shower on the passenger side from the water source on the driver side. I’m also going out on a lark by installing an electric radiant heat pad 5’x16” in the middle of the floor. That might prove to be folly, but for $60, it’s with the gamble to me. It will be taped in place to the bottom of the plywood.

Under all this is the 4 gauge battery interconnect wire, buried. You are correct, I will never get to this wire. If it ever fails (nail puncture, etc.), I’ll run another wire under the van and up a weep hole, which was a helpful suggestion.

I, too, will take some pictures as I go. Thanks for your responses!
 

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Vandit, That is Great !!

Please post your photos on your thread here when you're done so it can help others.

Not sure if you're planning to chassis grounding your house battery negative, but that is what I did. I sized my red “Positive” from the starter battery 70amps & 3% voltage drop IIRC (16’ red positive plus 2’ for the negative house battery post to chassis ground = 18’ run total length). Your total run might be different as may your Amps & what you want for voltage drop

Good Luck !
 

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Not sure if you're planning to chassis grounding your house battery negative, but that is what I did. I sized my red “Positive” from the starter battery 70amps & 3% voltage drop IIRC (16’ red positive plus 2’ for the negative house battery post to chassis ground = 18’ run total length).
You have this miscalculated. The total run is way more than 18' due to your chassis choice for the negative leg.
And steel's (chassis) resistivity is an order of magnitude higher than copper's...

However you are in a bit of luck because you will seldom draw more than 50 A from alternator, depending on your particular B2B charging solution.
 

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You have this miscalculated. The total run is way more than 18' due to your chassis choice for the negative leg.
And steel's (chassis) resistivity is an order of magnitude higher than copper's...

However you are in a bit of luck because you will seldom draw more than 50 A from alternator, depending on your particular B2B charging solution.
Thank you for that, it is possible for me to be misinformed.

Do you have a website you can refer me to so I can read up on what you are stating regarding vehicle electrical systems & ground chassis returns?

TIA
 

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A chassis ground gets the job done and saves a little money and work by not using that much extra wiring.
It adds up when building 100s of thousands of vehicles p/yr. Maybe not so much a factor on a one-time camper build.
I'm running both pos and neg all the way back to the battery for a few reasons.
1: I'm using 2ga jumper cables for my run and they're already a pair. (With new ends, not alligator clamps)
2: grounding bolts are a point for possible corrosion and/or failure.
3: steel has more resistance. Probably less of a concern than #2, but since I'm already running full length wires for both sides, the lower resistance is just an added benefit.
 

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Thank you for that, it is possible for me to be misinformed.

Do you have a website you can refer me to so I can read up on what you are stating regarding vehicle electrical systems & ground chassis returns?

TIA
I am thinking I will not get a reply from @joylesshusband

Do any of you know what he was writing about & where I can find documentation regarding “ground chassis returns”?
 

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