Ok, I'll try and explain this the best I can, I am electrically impared. I'm putting a Rebel harness in my 50 Chevy. The wire that is marked selenoid power will not be used for that purpose. I am running a remote selenoid in the trunk and my car uses a pushbutton for the starter. My selenoid power wire will just go to a terminal block on the firewall and provide 12v to the rest of the fuse panel. Anyway, the wire is 10 guage and the kit came with a fusable link that I would like to replace with a maxi fuse. What amperage fuse should I run inplace of the fusable link? Thanks, Todd
Fuses are sized to protect the wire.. Therefore you would need a fuse for the maximum rating of the 10 guage wire. 30 amp would be a good start with a maximum of 40 if needed..
I reopened this discussion as I am confused . If your alternator outputs 125 amps and you have a 10 gauge wire rated at 30 amps where does the other 95 amps go? I am talking about the maxi fuse between alternator output and the battery. My American Auto wire kit uses a 10 gauge wire. another Painless kit used a 10 gauge wire.
if I understand your question try to think about the amp rating of your household wiring.most are 100 amp but each circuit running to outlets etc.are fused to prevent over draw protection.ie toaster draw 13 amp fuse 15 amp.if the toaster has a internal problem and draws more than the 15 amp fuse it should blow as the heat in circuit will blow.same principal applies to your car aside from the ac dc difference.what I am saying is the amps coming in to toaster are not the full 100 as the wire will limit amps. if you use heavier wire than you can use higher rated fuse due to less resistance to flow of amps.draw equals heat due to resistance.what I am saying that full 100 amps will never reach toaster due to wire.due to 100 amp supply you will be able to add different circuits as long as total circuits do not exceed the hundred amp supply.if you look at supply to house the in amp supply will be fused not to exceed 100 amp.same thing applies to your car.if you place fuse in line from alt. gen.if you have enough circuits drawing amps that exceed the fuse rating then it will blow.if you know total amp draw that every circuit draws when used at once fuse accordingly.I do not think you should blow the main fuse due to the fact that if a circuit draws too much amp. draw that fuse will blow not main fuse protecting supply.hope this makes sense it is a rough idea.I used house wiring as easy for most to relate to.your battery is a storage for supply power unless battery is bad the alt. gen. only keeps it topped up so will never run at full amps.this is where the regulator comes into play.the 10 gauge wire wire supplies battery fusing it will protect alt. or gen. from running full time in case of battery short or major short causing alt. gen. to overheat and burn out.think about black outs same principle.
If the total draw of the total of the circuits is 100 amps on a 10 gauge wire rated at 30 amps it is exceeding the 30 amp fuse. ????? Should the fuse be 100 amp?
The alternator is not a 100 amp load, amperage is load or current draw, the alternator is creating/generating voltage. Im no expert but i know the alternator is not a 100+ current draw. I would match the fuse to your wire size. Posted using the Full Custom H.A.M.B. App!
An altanator is a source or supply of voltage / current. If the system is drawing 100 amps the altanator is re supplying the battery. Posted using the Full Custom H.A.M.B. App!
WHY not use fusible links.They were good enough for the Big 3 automakers.Its usually 4 #s higher.For a 10 amp circuit use 14 gauge fusible link.
The text of this is about maxi fuses not fusible link. Thanks for your time. Posted using the Full Custom H.A.M.B. App!
The alternator supplies voltage, it does not draw current (amperage). Posted using the Full Custom H.A.M.B. App!
The fuse size needs to be 125% of the connected load, i.e. the maximum amount of amps that could be drawn. This could include ignition, headlight, dash, and taillights, radio (anything that would be continuously on), plus the largest intermittent load (only on briefly). The safe maximum for #10 wire without getting excessive voltage drop is 30 amps.
An alternator doesn't draw current, it produces the current that charges the battery and supplies the current for everything else. A 100 amp alternator can output 100 amps so it can push 100 amps through the wire connected to it. Think of electricity like water. Voltage is pressure and current is flow. The pressure[voltage] forces flow[current]. A bigger pipe[wire] can flow more water[current]. With electricity, it is electrons flowing through the wire. If there isn't enough resistance to flow in the circuit, the electrons flow too fast and create heat. A larger wire allows electrons to flow more slowly to create less heat. If you want to move 100 cars a minute past a point on a highway, you only have to have 25 cars a minute in each lane on a 4 lane highway or 50 a minute on a 2 lane highway. A fuse, circuit breaker or fusible link provide a means to stop the flow of electrons before the wire overheats and causes a fire. A fuse is easier to change than a fusible link while a circuit breaker can be reset or is self resetting. I like to go with larger wire and smaller fuses to avoid any chance of an electrical fire.
Is the fuse between the alternator and battery or between fuse panel and battery. Thanks for posting.
Never heard of a fused alternator. They connect straight to the battery. 10 wire seems small for an alternator.
The factory didn't and I never understood why. I've seen an alternator short out when a bearing fails and cause a fire. I have a 200 amp alternator on the truck I use to plow snow and I have 2 - 100 amp maxi fuses wired in parallel on it with 1/0 welding cable.
The positive battery cable , which should be a no. 1 gauge, is run from the battery to the main post on the starter. Then a 10 gauge wire with a fusible link is run from the + post on the starter to the alternator. The fusible link protects the alternator in case of a surge. This is how all of the wire kits I looked at were diagramed. I used a Rebel 9+3 kit which I bought from, ( oddly enough ) Tugmaster here. I guess this thread was started by him before he became a dealer. I've heard Todd was having some health issues and haven't heard how he is doing, maybe he'll post in and shed some light.
I'm no expert either but 14ga wire or fusible link is actually smaller not bigger than the 10ga wire. why would you want smaller? 10 ga is small I would think, but painless applications are supposed to be very good.
all manufacturers have a master or alternator fuse in case of the alternator shorting internally. usually 50 to 80 amps. check the output of the alternator in your daily or in your wifes ride, and then check the alt fuse rating, you'll see.
A fuse between the alternator and the battery is always a good solution. It needs to be at least 25amps higher than what your alternators maximum output is. Keep in mind that underhood temps lower your 10ga wires current carrying ability and changes the actual amp that a fuse will pop. I suggest using a much larger alternator charging wire (4-6ga) and then using a Maxi fuse of at least 100 amps. We at Painless just redesigned our alternator circuits to use a MIDI fuse instead of the old Maxi fuse we've had for decades. If you want more info on how to properly wire your charging circuit just let me know. We're here to help. Jeff Abbott Sparktrican
I know the post is about maxi-fuses thank you for the attitude but when using fusible links you want a 4# smaller than the current carrying wire so the link blows b4 your device your trying to protect .14 gauge protects 10 gauge 16 ga.protects 12 ga.,
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