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How many volts should a fully charged battery read?

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Old 08-22-2001, 05:17 AM
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Default How many volts should a fully charged battery read?

Is 12.14 low?
Old 08-22-2001, 05:18 AM
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no, car batteries are 12v, they usually run 14v when the car is moving
Old 08-22-2001, 05:28 AM
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Mine reads 12.6 with the engine and all accessories off.
Old 08-22-2001, 05:35 AM
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Default To answer your question, no. Your alternator should put out between 13 and 14 volts

and your battery should be right around 12 volts fully charged.

Why do you ask are you having a problem?
Old 08-22-2001, 05:41 AM
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Default Alternators put out 14.4 Volts AC. The voltage regulator converts that to 12 volts DC. The ...

chopped off portion of the wave is the noise that shows up in cheap stereo amp installs.
Old 08-22-2001, 06:01 AM
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Default what voltage regulator? Battery charges to 12V, Alternator generates 14.4V...

If you test the voltage in the car when the car is running (ie when alternator is generating power), you will test ~14.4V. There is no voltage regulator that brings this down to 12V at a high level. (<- Hmm, that may be inaccurate) Perhaps individual devices bring it down, but they probably bring it down to 5V. Amps tend to use the full voltage (while adding capacitance to stabilize the voltage), as you'll see most are spec'd out at creating more power at 14.4V than at 12V. If they had a voltage regulator to bring it down to 12V everytime, this 14.4V power increase wouldn't be possible. So, at the battery, there is 14.4V when the alternator is supplying power.
Old 08-22-2001, 06:01 AM
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Default That's fine, a little above 12 is good with the engine off...

A little below (11.2 or so) is bad.
Old 08-22-2001, 06:13 AM
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cars do have a voltage regulator, but I'm not sure how they work
Old 08-22-2001, 06:16 AM
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Re: 2.2 Volt per cell ... 2.2 x 6 = 14.2 Volt
Old 08-22-2001, 06:25 AM
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Re: Wrong! Sorry. The correct answer is 13.2 V


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