multimeter usage on battery drain

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Bertiedabus
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multimeter usage on battery drain

Post by Bertiedabus »

Hi folks,
I have a battery drain, I thought it was all fixed and then went down this afternoon. I have had new alternator which is charging well the split charger appears to be working. The advice has been to systematically remove fuses one by one to see what is draining the battery (there are a lot of fuses!!).
Can i use a multimeter to see if a small current is running through a fuse when the van is shut down? Would that show the source of the drain?
Excuse my ignorance!
Alex

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AdrianC
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Re: multimeter usage on battery drain

Post by AdrianC »

Bertiedabus wrote:Can i use a multimeter to see if a small current is running through a fuse when the van is shut down? Would that show the source of the drain?

Yes, you can. Set it to an "Amps" setting, remove the fuse, and put one probe on each of the terminals for the fuse. If everything's turned off, the only one you should see any current flowing on is the clock/radio fuse - and that should only be a tiny fraction of an amp.
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Footprint
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Re: multimeter usage on battery drain

Post by Footprint »

Safest way is to disconnect the battery completely, put the meter on a low resistance setting and connect it to the two leads of the van. Note the reading on the meter, remove fuses/disconnect stuff as applicable until the reading drops significantly.
Bear in mind that a reading of zero will almost never happen - even if nothing at all is wrong.
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jamesc76
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Re: multimeter usage on battery drain

Post by jamesc76 »

AdrianC wrote:
Bertiedabus wrote:Can i use a multimeter to see if a small current is running through a fuse when the van is shut down? Would that show the source of the drain?

Yes, you can. Set it to an "Amps" setting, remove the fuse, and put one probe on each of the terminals for the fuse. If everything's turned off, the only one you should see any current flowing on is the clock/radio fuse - and that should only be a tiny fraction of an amp.



only do this if you have spare fuses for your multi meter, most are rated at 10 amps and are not easy to obtain, and its soooooooooo easy to blow the fuse, just accidentally switch one thing on!


Use a bulb for safetey or even a http://www.ebay.co.uk/itm/Car-Fuse-Curr ... 4d03d1c1a8, which is made for the job!
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Bertiedabus
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Re: multimeter usage on battery drain

Post by Bertiedabus »

As usual you guys are all amazing..was going to order the doo dah from the link but the fuses in my van are not blade fuses they are the torpedo shaped ones, what kind of meter thingy would you recommend for that that is safe? link if poss?

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AdrianC
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Re: multimeter usage on battery drain

Post by AdrianC »

Bertiedabus wrote:As usual you guys are all amazing..was going to order the doo dah from the link but the fuses in my van are not blade fuses they are the torpedo shaped ones, what kind of meter thingy would you recommend for that that is safe? link if poss?

I've got one of these - seems pretty bomb-proof.
http://www.amazon.co.uk/Draper-60792-Di ... B0001K9XKW" onclick="window.open(this.href);return false;
A year and a half living in a Westy hightop... http://www.WhereverTheRoadGoes.com" onclick="window.open(this.href);return false;

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