mtparker18

Hey guys, I was wondering if someone can tell me what size fuse I need to use, or how I can find out. I want to put 2 fuses between my 2 batteries.

The fuse locations are circled in this crappy drawing I made, lol

88supramki

why on earth would you want to cut the circuit between your battery and alternator?

mtparker18

I was always told to put 2 fuses between 2 batteries. I guess I don't need to? I was told It would be better to do that in case the wire shorts or something like that.

88supramki

Why are you running 2 batteries? That's beyond overkill for just a JL 1000/1. Especially since the slash series amps have internal regulated power supplies. Save yourself the headache, put 1 fuse between the main battery and the amp and call it a day.

Plus is your picture you're running the fuses in the same line, it's not like if 1 blows the other is going to save the circuit.

mtparker18

I had the other Optima laying around so I used it. What if I were to just get rid of the 2 fuses?

88supramki

If you are really set on using a second battery, just use 1 fuse in the line as a precautionary measure. 2 in the same line doesn't really make sense.

mtparker18

So then what size fuse would I need?

Big Mack

iTrader: (1)

I don't see him cutting between the battery and alt...

Nope. You should put a fuse on the wire that travels between the batteries if you're not using a fuse block. Since you are, that's all the fusing you need.

Agreed.

Assuming he's running the amp off the aux battery for the shortest connection possible, he should fuse between that battery and amp with a fuse in the line between the two batteries for protection on that wire.

Are you simply putting the batteries in parallel with each other or using an isolator? If you're just putting them in parallel (from your drawing, this is what you are doing), you should put in the same size fuse on both lines.

As for two batteries, if they were significantly different in age, you may run into issues with one vampiring off the other.

Big Mack

mtparker18

I'm just running them in parallel. so what your sayin is, if I'm running an 100 amp going to my 1000/1, I want to put an 100 amp between the batteries?

Big Mack

iTrader: (1)

I know.

Correct. Whichever battery your amp is pulling from, it shouldn't exceed the 100A mark. If it does, you have an issue. In reality, you could pull well over 100A for about 3 seconds before it will start to come unglued, but we're mostly concerned about the dead short issue. That's what fuses are for.

BTW - very smart to ask PRIOR to the wire fire. Good plan.

Big Mack

mtparker18

That's what I thought. Thanks Mack!