Test CR123s w/ Radio Shack Multimeter

[candlelight001]

I just got a multimeter at radio shack that tests 1.5V and 9V batteries, is there a way to test cR123s with it? And to be clear, I use the DC voltage setting to test my rechargeable li-ion's? Thanks!

 

[mighty82]

Very hard to test those with a multimeter, too small voltage difference between full and empty.

 

[Burgess]

You mean, a 3 (or 4) digit Multi-Meter

doesn't have sufficient accuracy to test 123A cells under a load of known resistance ?



_

 

[zipplet]

It does have enough accuracy, easily - but I can't quote the voltages you are looking for

 

[candlelight001]

Just fooling around I find that brand new cells are around 3.1+, and fairly depleted ones are around 2.7ish... Is this enough to give me an idea of where my cells are at, or am I being misled...?

 

[zipplet]

It's better to test them under load but testing them without a load is good enough to give you an indication of "probably good" and "useless"

Does your meter have a 3V battery test position? I have one that does and it places a small load on the battery.

 

[candlelight001]

It has a 9V position that puts a 10mA load on it... I'm assuming that's too small to be useful?

 

[zipplet]

That's too small a load - at 3V it would put a third of the load. Also out of interest, does your meters battery test work by showing the voltage under load or by showing a "bad / good" state? It's only useful if it shows the voltage.

 

[candlelight001]

voltage. It puts the AA and AAA's under higher load but when I put the 123 on it it's off the scale.

 

[Burgess]

So how much load (Ohms) should we put across a CR123A cell,

in order to perform a meaningful Voltage test ?

_

 

[Lighthouse one]

You need to buy a ZTS tester...we all try to put it off, but you might as well just spend the money. It's the best way to test them. Get this model...not all will test the 123 batteries.

http://thomasdistributing.com/shop/...html?SP_id=&osCsid=icgg1ageirqsd9l32bfac4ce06

 

[SilverFox]

Hello Burgess,

I believe the ZTS uses a pulsed load of around 0.8 amps when testing the CR123 cells.

Tom

 

[Burgess]

Oh, a pulsed load . . . .


So, this is NOT something that could be (easily) duplicated with my DMM.



Correct ?



Guess that explains why everyone has chosen the ZTS meter.



Oh, and to LightHouseOne --

Thank you for that link.

:twothumbs
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[zipplet]

That's correct, I'm also of the opinion that a pulsed high current load is the best way to test a bettery under load. You could only replicate that by building a complete test circuit so it's not worth it, just get the ZTS

I need to get one myself at some point ... especially as I've now got a 2 cell CR123A light.