Battery Fuses

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Jon and Kay
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Battery Fuses

Post by Jon and Kay »

Is it necessary to fuse both sides of a 12v battery?

I currently have 300A fuses at the battery terminals (+ve and -ve), but have been thinking that the -ve fuse may be unnecessary?
Jon
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Dot
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Re: Battery Fuses

Post by Dot »

personally I always thought that there is no need for a fuse on the neg side, plus the fuse is not to protect the battery but is there to protect the piece of equipment that is drawing the power. How was that coming from me ? :)
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Jon and Kay
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Re: Battery Fuses

Post by Jon and Kay »

Dot...you're the new go-to person for everything electrical :)
Yes, it is primarily to protect the cables etc, downstream of the battery, although inevitably it does protect the battery should a short circuit not cause the cable to fuse :) (saw a video of a LFP taking 13 minutes to destroy itself after a short circuit http://gwl-power.tumblr.com/post/700178 ... rt-circuit )
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Re: Battery Fuses

Post by BernieQ2 »

You will all jump on me for this....I don't have a fuse on my battery's my plus cable its about one foot long to a fuse box that all my appliances are on , the negative goes to a buzz bar a bit further in distance as there are two batteries in parallel , positive off one negative off the other .
I never have had a fuse on my positive or negative just as my car and vehicle side of the motor home . The house and truck are not connected .
Motorhome 24v house 12v .
Bernie .
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Jon and Kay
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Re: Battery Fuses

Post by Jon and Kay »

Bernie, it is only one foot of cabling that is not protected. That seems reasonable to me in practice. Provided that short length of +ve cable before the fuse box is well insulated, I can't see any reason to jump on you :)
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SteveW
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Re: Battery Fuses

Post by SteveW »

Dot wrote:personally I always thought that there is no need for a fuse on the neg side, plus the fuse is not to protect the battery but is there to protect the piece of equipment that is drawing the power. How was that coming from me ? :)
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Re: Battery Fuses

Post by BernieQ2 »

6B&S Jon .
Bernie .
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Jon and Kay
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Re: Battery Fuses

Post by Jon and Kay »

My battery is connected via 0000B&S Bernie
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Re: Battery Fuses

Post by BernieQ2 »

So is my truck but no need for that heavy in the house .
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Jon and Kay
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Re: Battery Fuses

Post by Jon and Kay »

I'm running Lithium Bernie, with current draws capable up to 250 A. That's why I fused with 300 A fuses.
Jon

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