Two 12V batts....what gauge wire to connect?

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SoCalAngler
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Two 12V batts....what gauge wire to connect?

#1 Post by SoCalAngler » Wed Apr 24, 2013 6:07 am

I have two 12V batts connected in series for use with a 24V trolling motor.

Question.....What gauge wire should be used to connect the positive of battery #1 to the negative of battery #2? Batts are about 3-4 feet apart.

Currently, there is an 8/10 gauge wire connecting them. This is the set-up that came with the boat when I purchased. Seems to me that the wire it is not heavy enough, but I am not sure.

Thanks
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The_Hellbilly
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Re: Two 12V batts....what gauge wire to connect?

#2 Post by The_Hellbilly » Wed Apr 24, 2013 6:53 am

I'm not an electrician, but that doesn't seem big enough. One way to tell is if they are getting hot during usage. I recommend going to your local auto parts store and getting some standard battery cables to replace them. You can also use welding leads
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Re: Two 12V batts....what gauge wire to connect?

#3 Post by cwag911 » Wed Apr 24, 2013 7:11 am

+1 on the auto battery cables.
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Re: Two 12V batts....what gauge wire to connect?

#4 Post by Cycleman07 » Wed Apr 24, 2013 8:17 am

I ran mine on my previous boat with 8 gauge and had no issue.
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BobG
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Re: Two 12V batts....what gauge wire to connect?

#5 Post by BobG » Wed Apr 24, 2013 12:52 pm

If you search the Internet, you will find tables showing you for any given length and current (that's the number of amps you're pushing), what gauge of wire you should use.
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VaGent
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Re: Two 12V batts....what gauge wire to connect?

#6 Post by VaGent » Wed Apr 24, 2013 2:21 pm

SoCalAngler wrote:I have two 12V batts connected in series for use with a 24V trolling motor.

Question.....What gauge wire should be used to connect the positive of battery #1 to the negative of battery #2? Batts are about 3-4 feet apart.

Currently, there is an 8/10 gauge wire connecting them. This is the set-up that came with the boat when I purchased. Seems to me that the wire it is not heavy enough, but I am not sure.

Thanks
I would use nothing less then #4 between the batteries. it all depends on the amp draw being applied to the batteries but #4 is more then sufficient in most cases.
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MH Hawker
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Re: Two 12V batts....what gauge wire to connect?

#7 Post by MH Hawker » Thu Apr 25, 2013 3:00 am

Its all about the amp draw, the older 12 v 55 lb thrust motors draw around 50 amps, 8 gage is just fine for short runs and connecting them up, the newer 12/24 will still have a max draw of 50 amps on 12 v and 25 amps on 24 v so its fine, but on a longer wire run from the back to up front I would go with a 6 gage due to voltage drop.
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