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Alternators have a built in regulator that keeps the voltage at about 13.5 Volts. Depending on the load, the alternator may be putting out anywhere from just a few amps to full capacity of over 100 amps for some alternators. Batteries charge at anything over 12 volts and handle about 14 volts without any problem. You start causing problems for your battery and other parts of your electrical system when the voltage goes over about 15 volts. But then, if your regulator is working right that should never happen.

The current (amps) of an alternator does not vary. if it is a 100 amp alternator, the amperage coming out is always 100 amps.

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โˆ™ 2012-11-12 01:12:36
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Q: Why does an alternator not over charge the battery?
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Related questions

What makes a battery and alternator over charge?

faulty voltage regulator

What cause alternator not to produce power to start engine?

The alternator produces power to charge the battery. The battery powers the starter to turn the engine over.

Will a car start if the alternator is going out?

It will start if there is enough charge in the battery to turn the engine over. However if the alternator is weak then the battery will not be charged fully.

What does a battery charge?

A battery charges nothing it accepts a charge from the alternator.

What charge the car battery?

The alternator charges the car battery.

How can I test my alternator to see if it is discharging my battery?

You can have the alternator tested free of charge at just about any major auto parts store. By the way, a bad alternator will not "discharge" a battery - the alternator's function is to provide the charge to the battery. If the alternator is faulty, then it is not providing the charge necessary to keep other components from discharging the battery. I had the alternator tested and it was charging. If the alternator has a bad diode, it will discharge the battery. I replaced the alternator and everything is fine.

Can a car battery over charge it self in the car?

Sure, if the alternator voltage regulator is defective it can overcharge the battery.

Are there any devices that can charge up a car battery besides an alternator?

older cars had a generator ,not an alternator, but you can always use a battery charger to charge a battery

What should you do if battery was not charged before installing new alternator?

My advice is to charge the battery with a battery charger before starting the engine. You will be putting a heavy load on the alternator if you allow it to charge a dead battery. This could damage the alternator.

Can an alternator charge a car battery?

That is the purpose of an alternator. The keep the battery charged and to run all the electrics on the vehicle. However it is never a good idea to allow the alternator to charge a dead battery. This will put a strain on the alternator and may damage it.

What is the purpose of the alternator?

Charge the battery.

Just installed a new alternator and belt on 1999 blazer - the new alternator is very hot your husband has leather hands and says it very hot Everything is grounded properly?

is your battery Low or poor?? Charge your battery on slow charge for 8hrs to give it a good deep charge, Installing an alternator on a low or dead battery will ruin it and also not charge your battery properly.. An alternator is not a battery charger its a battery maintainer!!

How long do you run your car after a a car jump?

I assume you mean how long to charge the battery. You should never let the alternator charge a dead battery if possible. The alternator is designed to keep the battery charged but not to charge a dead battery. You put a strain on the alternator and it can cause a diode to burn out. Drive home and then put a battery charger on the battery to fully charge it.

ECU for a 1999 Kia Sephia?

put in new alternator but it will not charge battery. alternator was tested and found to be good. why wont it charge the battery?

Will car start if alternator is dead?

Yes, the battery starts the engine, and as long as the battery is fully charged the engine will start. The battery will loose it's charge if the alternator is defective and not replenishing the charge of the battery but the alternator has nothing to do with starting the engine.

Charge the definition of the charge of battery?

The official charge of a battery is measured by the specific gravity of the electrolyte. For a good battery and alternator, full charge is noted when the alternator output current is just enough to carry the load, plus a bit to maintain the battery, and the battery voltage is normal.

Why your alternator does not charge the battery in your Pontiac firebird 1991 v6 3.1l you have bought new alternator What shall you do?

Repair the alternator to battery connections or replace the battery.

2000 Dodge Stratus loses its battery charge you charge the battery car runs for 3 miles and dies out again Battery needs another charge What is the problem?

your alternator is not charging your battery..u need to get a new alternator

Can you eliminate alternator from car?

you need the alternator to charge the battery with no alternator when the battery drops to about 10 volts car will not run at all.

Does the motor charge the battery when you run the engine?

No, the alternator recharges the battery. Of course the alternator is turned by the engine.

Why battery do not charge if alternator and fuse are good?

The battery may be defective and not able to take a charge.

Why does the battery not charge?

Corroded or loose battery connections, loose alternator drive belt, defective alternator, or dead cell in the battery.

How do you know if alternator fuse is bad?

If the alternator fuse is bad, the alternator is not going to work properly to charge the battery. An alternator runs off the serpentine belt, with graphite brushes inside that conduct electricity to charge the battery.

Why new battery and alternator won't hold a charge when car is running?

The alternator does not hold a charge. It charges the battery. If it will not charge the battery then either the alternator is defective, battery is defective, or the connections are corroded or loose. You should read 13.5 to 15.5 volts at the battery with the engine idling. Check it with a DC volt meter. If you get less the alternator is defective. If you get much more the voltage regulator is defective.

How can you charge batteries?

With a battery charger or alternator.