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Breaker Rating Question

SpeedThrills

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This question is in relation to protecting a circuit in a battery-in-trunk installation.

The cable involved is 6 gauge, and I want to use a 60 amp breaker. I'm looking at this one: https://www.amazon.com/dp/B08RX5QN4P/?tag=atomicindus08-20

It's rated 12-48 volts. I'm using 12, of course. Does the voltage applied affect the amperage rating?

Similarly, this max fuse is 60 amps at 32 volts. Would the amp rating be different if used with 12 volts?
 
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Shiftless

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Nope. Just amperes.
I assume that battery is not the battery that runs the starter motor in your car. Big car stereo amplifier perhaps? Inverter?
 
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SpeedThrills

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I forgot to add the link to the maxi fuse. But you got the point.

I didn't think it affected it. If it did, the different amperage ratings would have to be listed, in addition to the different voltages. However, I am farrrrrrr from being an electrician.

No, it's not for the starter. It involves a cut off switch to be NHRA legal when the battery is installed in the trunk.
If it's wired per the NHRA rulebook, there are still hot wires (or at least one, I don't recall), going to the front, even with the switch off.

I've been following the advice of someone whose plan involves a continuous duty relay and a Ford starter relay (both in the trunk), that kills everything to the front of the car. This line feeds the system power for the car. It's a street/strip car with not much demand.

Thanks for the reply.
 

Shiftless

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Sounds like you’re on the right track.
Do you need ballast in the trunk to increase traction? I know Ford put batteries in the trunk for their 427 Fairlane drag cars back in the middle 60’s.
If you don’t need ballast, I don’t think you need a full sized 12 volt car battery to power that relay. Weight of course is the enemy of low E.T.’s
 
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SpeedThrills

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Sounds like you’re on the right track.
Do you need ballast in the trunk to increase traction? I know Ford put batteries in the trunk for their 427 Fairlane drag cars back in the middle 60’s.
If you don’t need ballast, I don’t think you need a full sized 12 volt car battery to power that relay. Weight of course is the enemy of low E.T.’s
Yes, it's about moving that 40# from the nose, to the right side of the trunk.
 

Shiftless

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I found a pic of the trunk of a ‘64 Fairlane Thunderbolt. Ford put a huge battery there to help with ballast over the passenger side rear wheel to help with traction. Power for the 100 special production cars came from a 427 V8 with extra high compression. Some articles cite 13.5 : 1

B3F663C9-AA30-4FFB-8D4F-36099D0FE60D.jpeg
 
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