battery fitment

[1977dodge]

i have been thinking about using the interior wheel arch boxes of my campervan for putting my 4 solar batteries in ,
if i seal them in and make them accesable from the outside would it matter that as they are wired in series that the connections from battery #2 to battery #3 were some distance apart ie the width of the van
i know long wire runs should be avoided but it would give me more room in the van if they are not using extra floor space.

 

[66788]

When multiple batteries are wired together, the jumpers should be as short as physically possible.

You have a lot of amperage between cells/batteries and a 6' wire run will lead to voltage/amperage loss if the proper (read that as HUGE) wire is not used.

I'd not do that and keep all 4 as close as possible.

 

[Optimistic Paranoid]

66788 is basically right.

If you felt you HAVE to do it, you're best bet is to run 4/0 welding cable from one bank to the other. $$$. Also, for longest battery life, you'd want to tap the positive lead from one side and the negative lead from the other, which can complicate your wiring a bit.

Regards
John

 

[gadgetMe]

I say it is totally doable. Using 4 gauge wire will work just fine, I have found that if you purchase the cable from a welding supply house it will be quite a bit less expensive to buy ( as they are accustomed to selling cable in bulk)
Use good quality copper lugs for the ends.
I am assuming you are using 4 - 12 volt batteries (opposed to 4 - 6 volt batteries, which is what I use)

I have used 4 gauge wire to run 25 ft from the front of the vehicle to the back without any troubles.
Since you are using it for a solar system your amperage demands will be low compared to someone using them to start a vehicle..

More good information on battery systems check out 12 volt side of life link

 

[66788]

I think you meant to say use 4/0 gauge wire and not 4 gauge wire. There is a big difference between those two sizes.

 

[Optimistic Paranoid]

I'm going to respectfully disagree with you about the wire size.

4 gauge wire might be adequate to handle the intake from the solar panels, but you didn't ask about his planned loads. If he's thinking about running a large inverter off of it, he should wire the intake to the inverter with 2/0 gauge at a minimum, which means all the interconnections between the batteries also need to be 2/0 as well - and that's if the batteries are right next to each other. With half of them 6 feet away, he really should be going bigger between the two banks.

I suggested 4/0 because I was specing it for a worst case scenario.

Even if he's not planning it now, the bigger wire will let him add something like that in the future - if he finds his needs have changed - without having to rip everything out and start over.

The 12 volt side of life is a good read. I would also suggest Handy Bob's solar site as well.

Regards
John

 

[TucsonAZ]

No point in talking about wire size without knowing voltage. I would not run a bank like that, it will cause issues, can you, yes, is it ideal, no, on a scale from 1-10 you're talking about a 3 or maybe a 4, meaning it will work but on the lower end of acceptable. It will also require large wires!

 

[highdesertranger]

just a tip. welding cable is not the best choice for automotive installations. sure it will handle a lot of amps, but the insulation is not up to automotive standards. you can get cable that is comparable to welding cable with the proper insulation. can't remember what it is called at the moment but will look it up and post it latter. highdeserranger

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ok I found it you want to use sgt, sgx, or sgt-m. sgt-m is marine cable. highdesertranger