Printer Friendly Forum Posts - hooking up an extra battery

That's alot of fuses. =)

This is a technically acceptable way of wiring your car up, but you will probably find some dead batteries fairly quickly - you really can't wire two different batteries - or the same batteries of different ages - together like that. Paralleled in that manner one battery will have a slightly lower internal resistance than the other, and that battery will drain the other while the vehicle is off - purchasing batteries of identical design and identical ages does negate this however.

I would recommend you get a second Yellow, and wire them up together in precisely the manner you've drawn up above.

Have you purchased that first yellow yet or what? They're might be some more cost effective solutions - what are you running off this charging system anyway?

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"I'm finished!" - Daniel Plainview

so all those fuses are necessary? Also im going to be running about a 2500 watt system. And I know i will upgrade my ALT when i get the chance! But for now its just batteries. So if i get a yellow top under the hood and in the back it will do good?

I was also told i should fuse each 4 gauge power wire after the distro block. Since my amps dont have a fuse

mazzasec wrote:

so all those fuses are necessary?

Naww - but with two batteries its probably a good bit of prevention. Fuse (or circuit break) within 18 inches of each battery - IMO this is all that is really needed.

mazzasec wrote:

a 2500 watt system

This can mean alot of things. What amps are you going to run? Link to the product pages.

We might be able to design you a passable charging system much more cost effectively.

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"I'm finished!" - Daniel Plainview

An even better way, as I see it, would be:

1: Two identical batteries, even age. NEVER parallel different types or ages of batteries.
2: Instead of running from the from battery to the back battery, run from the front battery AND the back battery to the distro. You can save yourself a fuse and fuseholder, AND minimize connections between the alternator.
3: This will also allow the batteries to power the amplifiers equally, due to the minimization of connections between the front and the amps. Twice the current capacity, without straining either battery. Longer battery life.

Other suggestions to come as the thread fills out.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

heamphyst wrote:

2: Instead of running from the from battery to the back battery, run from the front battery AND the back battery to the distro. You can save yourself a fuse and fuseholder, AND minimize connections between the alternator.
3: This will also allow the batteries to power the amplifiers equally, due to the minimization of connections between the front and the amps. Twice the current capacity, without straining either battery. Longer battery life.

I don't understand what you are suggesting here. How are you telling him to wire it?

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"I'm finished!" - Daniel Plainview

Like this... One less fuse holder, and equal load on the batteries.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

haemphyst wrote:

Like this... One less fuse holder, and equal load on the batteries.

I think i see what your saying. So i should run 1/o gauge from the front batt into the distro and then run 1/0 gauge from the back battery into the same distro right? the distro does have 2 1/0 gauge inputs. Also if i wire it your way i wont need an fuses for the 4 gauge?

Right now I got a Soundstream pca2000d that does 2000 watts at 1ohm and i got a jl e 6450 that does 75 watts x4 at 4ohm

I am thinkin of ditchin the distro though and just using the battery would that work to?

Sure, that certainly a better option than your first diagram.

Also, I still stress the importance of using identical batteries!

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Is it possible to use a cap as a distribution block? I have power wire running from front battery to back battery, from back battery to cap, then from cap 3 wires going to 3 amps.

what size fuse should i use for the end of the 1/0 gauge and what size for the 4 gauge?

audioman2007 wrote:

Is it possible to use a cap as a distribution block? I have power wire running from front battery to back battery, from back battery to cap, then from cap 3 wires going to 3 amps.

Sure, perfectly acceptable to that...

mazzasec wrote:

what size fuse should i use for the end of the 1/0 gauge and what size for the 4 gauge?

1/0 fuse for NO GREATER THAN 350A
#4 fuse for NO GREATER THAN 150A

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

ok this is what i got to go along with my diagram.

So i need to fuse the 1/0 gauge right before the second batt with a 300 a fuse. Then i need to fuse the 4 gauge going to the soundstream amp(2000 watts at 1ohm) a 150a fuse and then fuse the 4 gauge going to the JL amp (75 x4 at 4ohms) with like a 100a fuse?

Also wont i need a bigger fuse for the soundstream amp? I know i should be running 1/0 gauge to the 2000 watt amp but the inputs dont go well with 1/0 gauge so i just used 4

Ok now I got this.

I got one question about it though. Does the short run of 1/0 gauge coming off the battery into the distro need to be fused? Other then that how would this work shown in the diagram.

posted_image

Anything longer than about 12 to 18 inches should have SOME type of overcurrent protection included.

and waht you are showing there... that'll work just fine! :)

Again, ar you going to replace both batteries with identical batteries at the same time? You keep showing different batteries in your diagrams...

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

haemphyst wrote:

Anything longer than about 12 to 18 inches should have SOME type of overcurrent protection included.

and waht you are showing there... that'll work just fine! :)

Again, ar you going to replace both batteries with identical batteries at the same time? You keep showing different batteries in your diagrams...

So it will work fine. the 1/0 gauge coming off the 2nd battery will probably be less then 2 feet anyways.So I DONT need to fuse the 1/0 gauge coming off?

i would say no you dont have to fuse it as long as its under 18 inches...however id wait for haemphyst to comment however I believe that you should first answer his repeated questions about the batteries...

haemphyst wrote:

Again, ar you going to replace both batteries with identical batteries at the same time? You keep showing different batteries in your diagrams...

This in itself is going to make or break that setup really really fast so first off before you ask any more questions please post an answer to that question so they know that you understood its importance.

1: thanks, twobig... seems as though I am being a little bit ignored... posted_image

2: twobig is right, if you go TOO much over 24 inches, just for safety's sake, I'd fuse it...

There are distribution blocks that bolt directly to the battery terminal, as well, and I have seen them with fuse protection built in. If you can find one of those, you'll be GOLDEN!

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Yes i will be having 2 of the same batteries. Not optimas though its this brand they sell at batteries plus. There 200 dollars and more powerful they optima d31.

So i do NOT have to fuse the short run of 1/0 gauge coming off the battery into the fused distro?