Do Fuses affect your voltage/Efficiency?

[MmatsDude 10+ year member]

Anyone?

I was also wondering who here has a fuse in there big 3(between the positive of battery to alternator) Is this fuse really important or recomendable to have? Im plannin on not running one there.

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[Pioneer~Saturn 5,000+ posts]

Well, anything inline with the wire(s) that has to add another connection point or two will add some resistance but very little. I myself will be putting a 300 amp fuse on each of my alternators' positive runs to the battery just because ive seen horror stories about connections coming loose a bit and the alt almost catches the car on fire.

And i will also have a 200 amp fuse on each end of each positive run to the rear soon...it sure as heck adds costs but safety is always a must especially if its a daily driver...but I could easily see why you wouldnt fuse a comp-only car where you have like 12 runs of pos and 12 runs of negative power wire running up and down the car

I dont think it would make an extreme difference though

 

[Cameron_B 10+ year member]

Anyone?
I was also wondering who here has a fuse in there big 3(between the positive of battery to alternator) Is this fuse really important or recomendable to have? Im plannin on not running one there.

Although you can never be to safe, most cars don't come with a fused Alternator-battery.

Then again....whats $20 bucks when you are talking about your car going up in flames.

Fuse it! LOL

 

[lilmaniac2 5,000+ posts]

Although you can never be to safe, most cars don't come with a fused Alternator-battery.
Then again....whats $20 bucks when you are talking about your car going up in flames.

Fuse it! LOL

I agree completely. Also remember factory wiring is much smaller and is usually loomed and engineered not to move EVER, Fuse it.

 

[Rashaddd 5,000+ posts]

Although you can never be to safe, most cars don't come with a fused Alternator-battery.
Then again....whats $20 bucks when you are talking about your car going up in flames.

Fuse it! LOL

but at the same time when's the last time you read/heard about a car that went up in flames because of an alternator wire grounding out

in the end, yes every fuse adds another voltage drop, which make more and more of a difference the more current you're drawing, so its up to you to decide whether its worth the risk not fusing certain places to avoid the extra cost/loss of power transfer. Personally I don't fuse the alt to bat wire

 

[Rashaddd 5,000+ posts]

I agree completely. Also remember factory wiring is much smaller and is usually loomed and engineered not to move EVER, Fuse it.

good point

 

[jrwalte 10+ year member]

I loomed and secured my own 1/0 alt to bat. I didn't fuse it either.

 

[knukonceptz 10+ year member]

Fuses can cause a loss of voltage usually about 0.25v, but can be as high as 0.40v. This is from the smaller element within the fuse compared to the wire it is connected to. To combat this you can run many smaller fuses together. So say you have 150A fuse, three 50A fuses cold be stacked and would reduce your voltage loss since it would increase surface area of the fuse itself. Thats why you see the MECA guys running many 5 or 10A fuses, to get every last tenth of a volt through the fuses.

For everyday vehicles, its probably best to fuse the added wiring. As said, its $20 and could be the difference in your car being wrecked and on fire or just wrecked....