01 F150: Fusible Link

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Old 11-19-15, 10:50 PM
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01 F150: Fusible Link

Hey guys! I haven't been on here in forever. But anyway, here's what I'm wondering: What is the amperage rating of the fusible link for an 01 F150, with the 5.4L gas V8? All I can find is it's 2 #12's in parallel, which doesn't help me much. I'm putting in a heavier alternator because of my inverter, and am upsizing all my wiring. I want to also replace the fusible link with a circuit breaker. Thanks to whatever help you guys can give me!
 
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Old 11-20-15, 04:39 AM
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How much more juice is the replacement alternator going, to produce? Will the computer understand the change? How can you possibly "upsize" all the wiring? You might want to contact an auto electric shop.
 
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Old 11-20-15, 08:19 PM
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That's what a fusible link is. It's a piece of wire or wires that is under the maximum rating of the circuit. In case of a short they burn open instead of the harness burning up. Two #12's is a pretty hefty amperage.

You want to use a circuit breaker between the alternator and the battery bank. I don't think those 12v circuit breakers are up to the task. They are good at protecting loads but you're going to be moving a lot if current thru it. You'd have to consider a 250A or 300A breaker.

I'd use a 300A ANL fuse and fuseholder.
 
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Old 11-22-15, 11:23 PM
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That's what a fusible link is. It's a piece of wire or wires that is under the maximum rating of the circuit. In case of a short they burn open instead of the harness burning up. Two #12's is a pretty hefty amperage.

You want to use a circuit breaker between the alternator and the battery bank. I don't think those 12v circuit breakers are up to the task. They are good at protecting loads but you're going to be moving a lot if current thru it. You'd have to consider a 250A or 300A breaker.

I'd use a 300A ANL fuse and fuseholder.
300A?! The wire looks only like a #4 or #2. The alternator is only 95A currently.
 
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Old 11-22-15, 11:34 PM
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The fuse or fusible link is for catastrophic failure protection aka a dead shorted alternator.

What are you upgrading the alternator to and what size wire are you using ?

I have two 150A alternators on my Ford diesel van. Each alternator has it's own 250A fuse and are connected with #2 fine strand cable.

Too small a fuse in a high amperage/high heat location will fatigue and fail.
 
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Old 11-22-15, 11:58 PM
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The fuse or fusible link is for catastrophic failure protection aka a dead shorted alternator.

What are you upgrading the alternator to and what size wire are you using ?

I have two 150A alternators on my Ford diesel van. Each alternator has it's own 250A fuse and are connected with #2 fine strand cable.

Too small a fuse in a high amperage/high heat location will fatigue and fail.
Ahh I see. I have been able to find up to 300A so far so that's what I think I'll use. Either 2/0 or 4/0 stranded copper wire. Would welding wire work?
 
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Old 11-23-15, 12:09 AM
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Welding cable is great if you can afford it.
 
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Old 11-23-15, 10:30 PM
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Welding cable is great if you can afford it.
I have a bunch on my scrap pile

So it looks like:
4/0 between batteries.
4/0 on 400A fuse to alternator.
#2 on 150A breaker to factory harness.
#2 on 150A breaker to inverter and inverter battery.

Sound ok?
 
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