Big 3 Question

[1rockford1 5,000+ posts]

so what happens when the fuse blows, and both sides are still hot? alt would keep one side hot, battery on the other side. i don't see wtf good a fuse does there.

for my self if u got everything on nice and good u dont have to spend the 20+ for a 1/0 ga fuse holder and a fuse..

 

[jco1385 5,000+ posts]

either it's on there right, or it isn't. the only difference would be where you run the wire.

 

[natisfynest 10+ year member]

if your gonna fuse you should do 2 fuses on the wire from alt to batt IMO 6 inches from alt and 6 inches the batt. BUT I dont see the need for any fuses the factory doesnt use fuses and as long as your wire isnt in a compromising (sp?) spot then i dont see the need

 

[loopkiller 10+ year member]

Actually, here is my take on the whole fuse or not fuse the POS+ alt wire debate.

1) If this wire needs protection from over current, then a single fuse will do the trick. It does not matter if you have more than one for this purpose and it does not matter where it is located.

2) If you want to protect this wire from dead shorts, then you have to consider where the short might occur. Since both ends of the wire are a potential source of POS+ power, then one would assume that you need a fuse at both ends. Let's consider the scenarios:

a. The wire is severed near the battery and that end contacts ground. The power from the alt is now dead shorted. A fuse near the alt output is necessary to protect against this type of short.

b. The wire is severed near the alt and that end contacts ground. The power from the battery is now dead shorted. A fuse near the battery output is necessary to protect against this type of short.

So in the end, if you simply want to protect against excessive amperage on the wire leading to a fire, one fuse at either will do. If you want total protection against shorting and over current, you will need one on each end of the wire.

If you don't mind your car looking like this picture, you don't need any fuses:

 

[jco1385 5,000+ posts]

i guess i'm driving a ball of fire, in waiting. lol

 

[hornedfrog1985 5,000+ posts]

I'll join you.

 

[loopkiller 10+ year member]

i guess i'm driving a ball of fire, in waiting. lol

To be honest, anytime you have a battery in the car that has that much stored energy, you have a risk of fire. There is no way to absolutely remove 100% of the risk involved. You seem like an intelligent guy, so you are not the guy I worry about telling us about his burnt car story. I am just trying to educate the noobs that come here looking for our advice. If they take 50% of my uber strict advice, they will likely be fine. If they take 50% of the advice from the guys saying fuses are a waste of money, then they will likely burn.

 

[MkKin420 10+ year member]

Agree completely with LK. One of the main reasons the manufacturer may not have fused the alt to batt is because of how they routed the wire. Often the factory wire will be routed around the engine and through all sorts of paths that the manufacturer deemed to be safe enough for the unfused wire to be placed. Basically they route the wire in a path that does not come near moving parts, very hot parts, ect. When you add an additional wire from the batt to the alt chances are you are going to have to route it near all sorts of parts. Fusing may seem pointless but as da Loop Killer said, "If you don't mind your car looking like this picture, you don't need any fuses:".

 

[jco1385 5,000+ posts]

To be honest, anytime you have a battery in the car that has that much stored energy, you have a risk of fire. There is no way to absolutely remove 100% of the risk involved. You seem like an intelligent guy, so you are not the guy I worry about telling us about his burnt car story. I am just trying to educate the noobs that come here looking for our advice. If they take 50% of my uber strict advice, they will likely be fine. If they take 50% of the advice from the guys saying fuses are a waste of money, then they will likely burn.

ilu //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

and you should ALWAYS run wires where there is no risk of heat damage, rotating parts, pinch points, etc... then you are WAY less likely to run into a situation where the wire is compromised, therefore using/needing the fuse (that i don't have, lol).

 

[loopkiller 10+ year member]

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