# Engine Battery at rest 12.2v! is this OK?



## alshymer (Nov 4, 2007)

Hi
Although I have BatteryMaster, an Efoy and solar panel, my engine battery always seems to be at around 12.2v.
This seems to me to be somewhat low and I don't know of a power source that would be running off the battery at rest, save for a Strikeback.
Any ideas?
Thanks as always.
Best wishes
Alshymer


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## rayc (Jun 3, 2008)

How is it being measured?


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## listerdiesel (Aug 3, 2012)

Sounds well too low, a fully charged battery at rest should be 12.60 to 12.80 volts.

Peter


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## alshymer (Nov 4, 2007)

*engine Battery*

Hi
Thanks for replies.
I am taking the reading from the Hymer control panel.
The battery is a good quality Bosch Silver which has been on two years.
The engine 3Ltr Fiat.
Kind regards
Alshymer


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## EJB (Aug 25, 2007)

Put a new battery in my MH last year...the old one was at least 7 years old.

Old battery:-
With a mulimeter the readings went down to 12.3/12.2 Volts after 2 or 3 weeks when static (Alarm on)...all year round.

New battery.
Readings down to 12.4 Volts after 5 or 6 weeks (Alarm on)....winter time.

The last few months have seen our MH static for longer than ever before due to other commitments....but things will change as we get back to normal :wink:


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## rayc (Jun 3, 2008)

*Re: engine Battery*



> alshymer said:
> 
> 
> > Hi
> ...


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## nicholsong (May 26, 2009)

*Re: engine Battery*



rayc said:


> > alshymer said:
> >
> >
> > > Hi
> ...


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## Penquin (Oct 15, 2007)

My control indicates 12.3 whereas two different voltmeters across the terminals read 12.6, I suspect the voltage drop to control panel is due to the length of wire....

If you check it at the terminals that should reassure you that everything is OK.

Dave


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## 113016 (Jun 5, 2008)

Another thing.
Don't forget, batteries are never at their best when they are cold.
I am thinking of this cold weather we now have.


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## pieterv (Feb 3, 2009)

Penquin said:


> My control indicates 12.3 whereas two different voltmeters across the terminals read 12.6, I suspect the voltage drop to control panel is due to the length of wire....
> 
> If you check it at the terminals that should reassure you that everything is OK.
> 
> Dave


A voltmeter shouldn't really have much in the way of a voltage drop as they hardly use any current (unless something else being fed through the same wiring takes a fair bit of current).

But still, as advised, measure at the terminals with a decent volt meter, the control panel one might be out for other reasons.


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## 747 (Oct 2, 2009)

I think Dave means the voltage drop caused by long runs of miserly thin wire used by Manufacturers.

It was only around 10 volts by the time it got to my high level rear marker lights on my last van. 8O


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## pieterv (Feb 3, 2009)

747 said:


> I think Dave means the voltage drop caused by long runs of miserly thin wire used by Manufacturers.
> 
> It was only around 10 volts by the time it got to my high level rear marker lights on my last van. 8O


Yes, but voltage drop gets caused by resistance AND current (Ohm's law V= I x R). Your lights will use a much higher current than a voltmeter, a voltmeter on its own will hardly cause a voltage drop because of its low current requirement and therefore can be connected by thin wires.


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## alshymer (Nov 4, 2007)

*engine Battery*

Hi
Thanks for all your replies.
We are at Javea at the moment and the weather good, apart from today, which has been wet.
Therefore I am surprised that the voltage drops so low. When the rain stops I will check the terminals as advised.
Best wishes
Alshymer


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