Battery voltage

ciderman · Apr 15, 2011

Hello.
What voltage does your battery get to?
i have a halfords Calcium battery on my series 3 which has charged up to 18.36 Volts.
my clever chum says "turn the lights on and reduce the charge"
3 hours with main beam on and its about 17 volts.
The side lights are very bright!
should i worry?
Ideas please on a postcard....

The Mad Hat Man · Apr 15, 2011

yo alternator is fuct and has done the same to your battery

oxides · Apr 16, 2011

Is that with the engine running? Could be your meter's buggered.

mystery · Apr 16, 2011

just out of curiosity you have got your meter set on DC voltage range

tottot · Apr 16, 2011

Over charging alternator will soon fry a battery

ciderman · Apr 17, 2011

OK, yes the meter isn't calibrated and the battery voltage state is from the battery charger,
left on for 24 hours.
i will check the voltmeter but it is a clever calcium battery..
sealed for life.
mine or the battery's?

oxides · Apr 18, 2011

All about batteries:-
Automotive battery - Wikipedia, the free encyclopedia
Even your clever calcium battery shouldn't go higher than thirteen and a half volts fully charged and disconnected. You shouldn't see more than fourteen and a half volts at the battery when connected and with the engine running

ciderman · Apr 19, 2011

All is now clear:
the test meter is F**ked.
and my mate made me leave the lights on for 3 hours to "bring the voltage down"
huh!

pobby · Apr 19, 2011

With the engine running and nothing switched on you should get 13.8v to 14.2v
That would be a perfect charge
When the engine is not running you should get no more than 12.5v maybe 13v on a big battery
If your getting more then the alternator is buggerd and that will cook a battey in no time
If with the engine running and everything switched on you should get no less than 13.2v
If you do then it's not charging enough and will cause the battery to run flat over as there isn't enough volts to recharge and run everything together

TheKeymeister · Apr 19, 2011

They only run at 2.1v per cell roughly (x6 for a 12v battery) so I can't see any physical way you could get 17 odd volts open circuit! With the alternator running maybe, but not with it disconnected.....

ciderman · Apr 24, 2011

OK OK OK.
i get the message.
the Ashcroft box is a good conversion..

ciderman · May 17, 2011

The test meter died today.
no flowers.
donations to the home for bewildered land rover Owners

Battery voltage

ciderman

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The Mad Hat Man

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oxides

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mystery

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tottot

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ciderman

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oxides

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ciderman

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pobby

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TheKeymeister

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ciderman

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ciderman

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