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The minimum RPM is highly dependent on the specification of alternator. But a basic alternator will produce charging current anything above 2000 rpm. We can safely say, an economy car will idle around 750 rpm, a sports car around 1250 rpm and a race car around 2000 rpm.
Does RPM affect alternator charge?
The faster the speed of the alternator, the faster the battery will be fully charged. As shown in Table 3, at idle speed 750 RPM, even after 5 minutes, the voltage reading was nowhere near the fully charged value. A battery voltage reading of 13.7 V and above while the engine is running is consider as good.
What is the minimum RPM start the alternator charging?
As was stated before, most alternators prefer a minimum speed of 2,400 rpm.
What should an alternator charge at idle?
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.
What is the minimum RPM of a 12v car alternator?
Typically, the lowest speed at which a car alternator is able to generate 12VDC is about 1,800 RPM.
How do I make my alternator charge more?
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).
Does higher rpm charge battery faster?
The battery will charge faster if you rev the engine faster. And the faster the alternator turns, the more electricity it produces to run all the electrical stuff in the car — and recharge the battery. But we don’t recommend that you use it that way for a weak or dead battery.
What should a 12 volt alternator charge at?
A car alternator needs to be putting out at least 13-14 volts (ideally between 13.8 and 14.2 volts) to effectively charge a 12 volt car battery.
Can you over rev an alternator?
So the alternator has to spin quite fast and has a pulley ratio of between 2 to 3 times faster than the engine rpm. The engine has a normal operating range that is set by the red line maximum rpm. If the alternator is switched to a higher revving engine without changing the pulley ratio then it can be over-revved.
How much horsepower does it take to run a car alternator?
An alternator takes about 1 HP for every 25 Amps of power. At full output, a 100 Amp alternator will need about 4 HP. For a long time, most alternators don’t operate at full output.
Is 13.2 volts good for alternator?
For some alternators, it’s normal to see as low as 13 volts. For some, a constant 13.6 volts is an indication of a problem. For others, it’s normal to see as high as 16 volts for long stretches. Still, it’s perfectly normal for others to see the alternator not charge at all intermittently.
Is 13.8 volts good for alternator?
With the engine running, use a voltmeter to measure voltage at the battery. At that point, if the voltage falls between 12.6 and 13.7 volts, you need to replace your alternator. If it’s greater than or equal to 13.8 volts, a voltage drop test needs to be performed.
How many volts is too low for alternator?
A car alternator needs to be putting out at least 13-14 volts (ideally between 13.8 and 14.2 volts) to effectively charge a 12 volt car battery. If the alternator is putting out too much voltage (15+ volts), it is likely your battery acid will boil over out of the battery.
Can you charge a car battery by turning the alternator?
The battery has the responsibility of providing the power to start your car. In order to fix a dead battery that is still carrying a good amount of voltage, driving around might be all you need to do. As we said before, the alternator will recharge the battery while your car is in motion.
How many kwh does an alternator produce?
at a charging voltage of around 14 Volts that yields in 560 to 770 Watts. In modern cars alternators have outputs between 70 and 180 Amps! especially when catalytic converter systems with heating elements etc are used. Sometimes alternators are water cooled as well (BMW 150 Amps).
How many rpm does it take to charge a car battery?
The higher revs will charge the battery faster…it is the engine that drives the alternator…at fixed engine revolutions, the gearbox increases the speed of the car. There is no need to over rev. the engine to charge the battery, about 1500 rpm’s will be ample.
What is the exciter wire on an alternator?
The exciter wire is used to turn on the voltage regulator. This wire, when unplugged, should have approx. 12.5 volts with the key on. If it does not then the alternator will not work.
What happens if you put a lower amp alternator on my car?
You will do no harm installing a higher output unit as the amps are on demand. Now if you install a lower output unit then you will have issue with the battery not being fully charged and the alternator not supplying the required power and the car running more off the battery. This will leave you stranded.
Does revving the engine in neutral charge the battery?
As the battery receives these charges, its voltage appreciates which is referred to as charging. Essentially, therefore, so long as this cycle is executed even when the car is in neutral, the battery will get charged. That means revving the engine in neutral charges the battery as it should.
Does idling car drain battery?
Over time, idling can cause your head gasket, spark plugs, or cylinder rings to deteriorate and stop working. Drains car battery. Idling does not allow your battery to charge and causes it to strain.
Does idling charge your battery?
Does the Battery Charge if You Let the Car Idle? The simple answer to this question is yes, your car’s battery will start to charge as long as your engine is running.
