Dual battery wiring tutorial (and why)

[loopkiller 10+ year member]

Sorry I was AFK for a little while, seems like I missed a big discussion here.

Buck, you can use wire or buss bars for that application. Those are small batteries and are simply not able to pass very much amperage. You will not likely exceed 300A out of the little 800. The 2000 may be able to produce near that much at 12.0V, but I doubt it. So unless you were powering stuff that would drop the voltage really low, like 10.0V or below, you are not going to get more than 300A out of them. You could do a load test and see what voltage they drop to with a 300A load.

As for why others use buss bars, because they use much larger batteries that in fact can and do pass over 300A per battery. In that case, you would use buss bars vs multiple runs of 1/0 awg between each battery in a bank.

As for which type of metal is preferred, brass, copper, and aluminum are some popular choices. I don't think you could exceed the capacity of any of those metals with small batteries.

As for how to attach buss bars to inset battery terminals, you could use a variety of things. First thing I thought of was copper pipe or tubing cut to length. JCO mentioned washers, but I think a small section of copper tub / pipe would be more stable. Either way, a longer bolt is needed. Those should be M6 threaded inserts.

Also, if you are going to use buss bars, know that there is a greater risk of shorting because you will have exposed conductors. I would stick with 1/0 awg wire //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[TurdFergueson2 5,000+ posts]

Seems to me like the ground to chassis for the second battery is redundant.

I was thinking the same thing, but I'd still do it.

 

[audiolife 5,000+ posts]

better to be safe than sorry and overkill>underkill anyday of the week...

 

[JarvisB 10+ year member]

Some people again would tell you to not wire this to the battery, but instead to the chassis. This would be OK if you did not have a rear battery and you had a very small amp. But since this discussion is assuming the rear battery is installed, you need to wire the NEG- connection for the amp directly to the battery.

right now I am going to go with just one HC2400 under the hood..

so do I still have to run a wire fom my amp's negative to my battery's negative terminal? or I will be fine with grounding the amp to chassis in the back?

 

[jco1385 5,000+ posts]

right now I am going to go with just one HC2400 under the hood..
so do I still have to run a wire fom my amp's negative to my battery's negative terminal? or I will be fine with grounding the amp to chassis in the back?

you will be find grounding to the chassis. no need to pull all the way back up front. this is just a standard amp install. just keep the grounds short and clean.

 

[Buck 5,000+ posts]

Sorry I was AFK for a little while, seems like I missed a big discussion here.
Buck, you can use wire or buss bars for that application. Those are small batteries and are simply not able to pass very much amperage. You will not likely exceed 300A out of the little 800. The 2000 may be able to produce near that much at 12.0V, but I doubt it. So unless you were powering stuff that would drop the voltage really low, like 10.0V or below, you are not going to get more than 300A out of them. You could do a load test and see what voltage they drop to with a 300A load.

As for why others use buss bars, because they use much larger batteries that in fact can and do pass over 300A per battery. In that case, you would use buss bars vs multiple runs of 1/0 awg between each battery in a bank.

As for which type of metal is preferred, brass, copper, and aluminum are some popular choices. I don't think you could exceed the capacity of any of those metals with small batteries.

As for how to attach buss bars to inset battery terminals, you could use a variety of things. First thing I thought of was copper pipe or tubing cut to length. JCO mentioned washers, but I think a small section of copper tub / pipe would be more stable. Either way, a longer bolt is needed. Those should be M6 threaded inserts.

Also, if you are going to use buss bars, know that there is a greater risk of shorting because you will have exposed conductors. I would stick with 1/0 awg wire //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

Thank you sir....And I have thought about that there are exposed wires as well.

 

[smoka 10+ year member]

Thank you sir....And I have thought about that there are exposed wires as well.

Just get some large heatshrink (or you can get some high temp insulation like used on engines) to cover the bar. Also don't use aluminum, because when it heats/cools it expands/contracts which will cause the terminals to loosen.

Also Buck, how do you have your batts strapped down? From those pics it didn't look too secure. Might want to get some backstrap and again cover it with heatshrink so its not exposed.

 

[jco1385 5,000+ posts]

you could hit them with some bed liner with the bolts in place. that should insulate.

 

[Buck 5,000+ posts]

Just get some large heatshrink (or you can get some high temp insulation like used on engines) to cover the bar. Also don't use aluminum, because when it heats/cools it expands/contracts which will cause the terminals to loosen.
Also Buck, how do you have your batts strapped down? From those pics it didn't look too secure. Might want to get some backstrap and again cover it with heatshrink so its not exposed.

That wasn't my picture, I was just giving an example of the terminals.

 

[bigbangtheory 5,000+ posts]

Yeah and many people have *** without a condom and never get AIDS....

But then again, millions of others have AIDS //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

Roll the dice if you want, I am simply pointing out the right way to do it.

I hear what you are saying. Just saying in the near 15 plus years I have been into audio, I have never ran an isolator with all of them being different setups. Many people run different batteries without an isolator without any problems.

Also I rarely use a condom and I am as clean as a whistle. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I do have kids to show for it though. //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

Also I have the worst luck in most things, but never with my batteries. I can't believe it!

 

[jco1385 5,000+ posts]

bump cuz this needs to be a sticky //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[taintedplay 10+ year member]

so if i have 400a pull on my amps, i should get 2 1/0g runs? or could i do like 1 1/0g and 1 4 or 8 ga run?

 

[loopkiller 10+ year member]

so if i have 400a pull on my amps, i should get 2 1/0g runs? or could i do like 1 1/0g and 1 4 or 8 ga run?

Why pull one 1/0 awg run and then one 4/8 awg run? Just run two 1/0awg and have capacity to spare. If it is a price thing, you should not be that far into an install of that magnitude to where you cannot afford wire. If it is a space issue, get creative.

 

[taintedplay 10+ year member]

k. two runs (4 total if include neg) of 1/0. ok, about fuses, wheres a place to get them? knu is like 25-30 bucks for a single fuse and fuse holder.

 

[loopkiller 10+ year member]

k. two runs (4 total if include neg) of 1/0. ok, about fuses, wheres a place to get them? knu is like 25-30 bucks for a single fuse and fuse holder.

You can get much cheaper ones if you want lower quality. You can find Scosche fuse holders for around $6 online. Fuses are cheap everywhere.