Date: Thu, 5 Nov 2015 22:39:13 -0500
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Multimeters
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At 08:20 PM 11/5/2015, Rob wrote:
>What David said.
>I put a meter on the AAA & read 1.2v, the print on the batt says 1.5v ... I
>get rid of it.
>Simple & a cheap multimeter will do the job .
Agree that a low voltage by regular voltmeter
indicates a bad battery. The problem is that a
nominal-looking voltage could be a fresh battery
or it could be a completely dead one that's lying
to you. The loaded test is reliable.
Yrs,
d
>Rob
>vwrobb@gmail.com
>On Nov 5, 2015 4:29 PM, "Dave Mcneely" <mcneely4@cox.net> wrote:
>
> > David, while that is technically correct, whenever I test a battery with a
> > multimeter for voltage, if it is low, and I try it in an appliance, I don't
> > get the desired response. If it reads close to or slightly above the
> > nominal voltage, I get the desired response, such as bright light with a
> > torch. I realize that the voltage I measure is not the voltage the
> > appliance sees due to load and loss variables, but it must be close
> > enough. Maybe if I were powering a scientific instrument which provides an
> > analog or digital readout, the readout would be off, but for everyday
> > household devices, I've had no problem. mcneely
> >
> > ---- David Beierl <dbeierl@ATTGLOBAL.NET> wrote:
> > > At 05:30 PM 11/5/2015, Anthony Egeln wrote:
> > > >I've been looking for a good excuse to buy a
> > > >moderately priced multimeter for quite some
> > > >time, and I think I may have one now.
> > > >Can you use a multimeter to check household
> > > >batteries? Â I have a box full of AA, AAA and 9V
> > > >batteries that my late mother had accumulated,
> > > >and while they may be out of date I want to make
> > > >sure they are really done before taking them to
> > > >our community hazmat pick up this Saturday. Â
> > > >I was going to buy a "battery checker" on Amazon
> > > >and I started thinking that a multimeter might
> > > >be able do this just as well and I'd have my excuse to buy the
> > instrument.
> > > >There are a lot of recommendations on the
> > > >archive for which multimeter to buy, but none
> > > >very recent. Â I'd love to have a current
> > > >recommendation for a moderately priced instrument, digital or analog.
> > > >Thanks, Ant
> > >
> > > Not really. To test a dry cell or dry battery
> > > you have to load it with something approximating
> > > a working load. Digital meters in general have
> > > ten megohms input resistance. My Radio Shack
> > > puts a 50 mA load on AAA, 150 mA on AA, C, D
> > > cells. 3 mA on button cells and I'm not sure on
> > > the rest. Ideally you'd dial in your desired
> > > load and cutoff voltage for your particular applications.
> > >
> > > Yours,
> > > David
> >
> > --
> > David McNeely
> >
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