What RPM does an alternator need?

An alternator has a normal range of operation. Most alternators need to spin at about 2,400 rpm at idle, have their maximum output above 6,000 rpm, and should never exceed 18,000 rpm.

How many RPM does a alternator need to charge a battery?

For battery charging to occur, the alternator's voltage must exceed the battery's voltage. Alternator may not generate sufficient charging voltage until alternator speed is greater than about 2000 RPM.

How much power is needed to spin an alternator?

Most alternators need to spin at about 6000 rpm or more to provide maximum output, and in most vehicles you will see max alternator rpm around 8-10000 rpm.

What should alternator output be at idle?

Most alternators that are charging properly should produce a voltage of about 13.8 to 14.2 volts at idle with the lights and accessories off.

Does an alternator charge more at higher RPM?

The charging capacity of the alternator and the quality of the connections. The engine RPM won't really matter as anything from just above idle will have the alternator at full output.

12V 64A Car Alternator Minimum RPM Test for 12V DC Output

Is alternator RPM same as engine RPM?

2 Answers. Show activity on this post. Alternators aren't built for one engine so the manufacturer can't possibly know the gearing / ratio between the alternator and the engine. Therefore the RPM listed in the spec will be the RPM for the alternator.

Does an alternator charge at idle?

Assuming the alternator, engine, belt, and battery are all in working order, then yes, a car battery will charge when idling. The only caveat is that it doesn't really “charge” that fast. This is solely due to the fact that the engine doesn't have a load on it when your car is simply idling.

What is a good alternator reading?

A good alternator should produce about 13.5 to 14.5 volts with the engine idling. If the voltage reading is low (12.5 volts or less), it indicates a charging problem but does not tell you what's causing it.

What is a bad alternator reading?

If the alternator is working well, your multi-meter should read somewhere in the vicinity of 14 volts (typically 13.8-14.2). If it is reading excessively higher than 14 volts (greater than 15 volts) it is possible that the voltage regulator on your alternator is faulty or going bad.

Can you use a car alternator to make a wind turbine?

When one uses a Delco car alternator as a wind generator, it is absolutely necessary to modify the alternator to operate at low RPMs. This is accomplished with two intricate modifications: One replaces the stock Delco car alternator stator windings with a stator that has more turns of smaller gauge wire.

Does revving car charge battery?

Yes, revving the engine will still charge the battery faster.

Is 14.7 volts too high?

14.8 would start to be a worry (there might be liquid or corrosion on the battery) and 15 volts would be a real concern, but 14.6 is fine. Less than 14.3 would be a "weak" alternator or regulator. Much less than 14.2 at a fast idle is bad wiring, bad alternator or regulator, or a bad connection or fuse link.

How can I test my alternator at home?

Can a weak alternator cause poor engine performance?

Driving around with a bad alternator isn't a smart idea; as damaged or broken alternators can cause a wide range of problems. They can interfere with your car's electrical features, make it harder to start the engine, and even cause the battery to drain entirely, leaving you with an utterly unresponsive vehicle.

Can an alternator overcharge a battery?

The build-up of hydrogen gas from an overcharging alternator causes your battery to swell. This also causes the battery to leak highly flammable liquid electrolyte, which is very dangerous. Please see a specialist right away if you notice this happening.

Does driving charge a battery faster than idling?

The simple answer to this question is yes, your car's battery will start to charge as long as your engine is running. As long as the electrical systems aren't draining the battery quicker than the alternator is charging it, it is technically possible to completely charge your battery using this method.

How long should I leave my car running to charge the battery?

Remember: After you've done a jump start, you'll need to keep the vehicle's engine running for around 30 minutes to allow the alternator time to charge the battery sufficiently.

How much torque does an alternator need?

If your alternator demand is for example, 2kW, then you need 2.7 HP from the motor to drive it. The details of RPM and torque vs. power you'd have to get from the alternator supplier. Typical alternators were 50-70A at 12V, or about 720W (roughly 1HP.)

Does speed affect alternator?

The speed of an alternator depends on the speed of the engine or turbine driving it.

How can I improve my alternator output?

Selecting different sized diodes can alter the output regulation of the alternator. A smaller diode will increase the charge voltage by more than a larger diode (due to the voltage drop varying with the diode current).

What is normal alternator output voltage?

A good alternator should maintain battery voltage between 13.9 and 14.8 volts (14.2 is optimum). Even worst-case, with all accessories turned on, there should be at least 13 volts at the battery.

Is 11.9 volts enough to start a car?

For a car with a 12V engine, the normal value before starting is between 12.2V and 12.8V, and it should not exceed 14.8V after starting.

Why is my car running at 15 volts?

Higher than 15 volts indicates a fault in the charging system's voltage regulator or related circuits. If it's substantially excessive, this can cause electrical system and/or battery damage. You mentioned your voltmeter runs at about 15 volts most of the time.