A/C reg. work as main fuse?

i'm curious to know if my A/C regulator on my 93' XR600 works as a fuse. I ask this b/c if i was to ever short circuit somehow, what theoretically keeps me from hurting my stator if there is no fuse to blow?

If a short happens in the wiring AFTER the A/C Regulator, nothing really bad should happen to the stator, but you'll probibly burn the wires around the short.. The regulator doesn't act as a fuse, but it will ground any power in that circut before it gets backfed to the stator. If the short were to happen before the A/C regulator, I bet you'd fry the stator...

You can fuse anything on the bike you want after the A/C regulator. Volts * Amps = Watts. Therefore Watts/Volts = Amps. If you want to fuse a 35w headlight; 35w/12v = 2.92 amps. I'd use a 3 amp fuse. A 55w bulb draws about 4.59 amps, so you'd need a 5 amp fuse.

i'm curious to know if my A/C regulator on my 93' XR600 works as a fuse. I ask this b/c if i was to ever short circuit somehow, what theoretically keeps me from hurting my stator if there is no fuse to blow?

The regulator works by shorting out the stator when the voltage gets to high. You don't have to worry about shorts frying your stator.

If you use small gage wire then you might have to worry about the wiring. The stator has limited output. With 16 gage or larger wire it will be safe for sure. 18 gage will start getting hot and 20 or smaller stands a good chance of frying if shorted.

Now if you have a DC system with a battery, it's a completely different discussion.

The regulator works by shorting out the stator when the voltage gets to high. You don't have to worry about shorts frying your stator.

If you use small gage wire then you might have to worry about the wiring. The stator has limited output. With 16 gage or larger wire it will be safe for sure. 18 gage will start getting hot and 20 or smaller stands a good chance of frying if shorted.

Now if you have a DC system with a battery, it's a completely different discussion.

Well, it's 50/50. The stator charges A/C current. The A/C regulator converts the A/C into D/C for the lights and the CDI. I have no idea how much power comes out of the stator directly, but the wires after the A/C regulator are all carrying a 12 volt D/C current.

I have never had a bad enough short, but my guess is the first vital part to fry will be the A/C regulator. If you had a short on the light wires, the buld will act as a fuse. If the CDI wires shorted, I don't know what would happen.

My Stator was rewound to have 2 outputs, 125 watts each. Each output could possibly carry 10.4 amps. 10.4 amps at 12 volts isn't enough to really be that dangerous.

Well, it's 50/50. The stator charges A/C current. The A/C regulator converts the A/C into D/C for the lights and the CDI. I have no idea how much power comes out of the stator directly, but the wires after the A/C regulator are all carrying a 12 volt D/C current.

Um, no. A DC regulator rectifies the AC from the stator into DC for a battery, etc. Usually only for a dual sport kit since many states require you red tail light to stay on for 15 or 20 minutes with the engine off. All an AC regulator does is limit the voltage from the stator. It does this by shorting it out for part of the AC cycle. The electricty is still AC.

Most Honda dirt bikes use a magneto style ignition. The lighting part of the stator is not involved with this function. There is a separate coil on the stator that supplies the high voltage for the CDI box.

If you disconnect your stator wires and connect them to a voltmeter you will see that at high rpms the voltage will go as high as 50 or more volts. The voltage is proportional to rpm. If it's 12 at 1500 rpm, it will be 48 at 6000 rpm. With no regulator you headlight would blow as soon as the revs increased. The regulator works by literally shorting out the stator for part of the cycle.

Anyhow back to the original posters question. Don't worry about your stator. You can't hurt it by shorting it out. Fuses are there to protect the wires. as long as you use large enough wire the stator can't fry them so not fuse is necessary.

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