My work issues us these headlamps :

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For our hard hats.

But unfortunately they take CR123 batteries.

It seems like that particular headlamp just absolutely eats CR123’s , especially in cold weather.

When I put in fresh batteries, I take the old ones home with me.

Could a person use a multimeter to check which ones put out more volts or amps?

Yep, but it sounds like they supply shitty batteries or the headlamps are shitty, or both.

Well, streamlight...

Do you use the high or low setting on the headlamp?

It doesn't work that way for current measurement (amps).  You would need a load tester.

Have you considered switching to rechargeables?

  Yes, it does work that way.

Edit. Thats why they are called "multi-meters." They measure lots of stuff.

Those battery's get corroded very fast. you cant see it but next time it dies, get a pencil and clean the battery with the eraser, and try them again.

Yes.

The easiest way to test most batteries is if your multimeter has a high amp current setting.
Many support 10 amps (usually by moving a test lead to the "10A" plug.)

Set the meter to 10A and briefly put the leads across the battery. This will tell you peak amps the battery
puts out. This, in turn, also tells you what the internal resistance of the battery is, and most batteries have
an internal resistance that increases in proportion to how much they've been used.

It's helpful to have a fresh battery to use as a guide to the peak amps a 100% battery will put out.

If you just test voltage, which a lot of people suggest (and some battery testers do) you just end up
measuring a surface charge and even near dead batteries can test at near 100%.

The ideal would be to have some low-value resistors like 10 ohm, 1 ohm and measure the voltage on those
across the battery, which would be a realisitic load simulation. Dead short using the amp meter is the next
best option.

The meter is not a load and must be placed in series to measure current. Touching the leads to the ends of the battery will not give you a current measurement. So no, it doesn't work that way.

ETA: Or a clamp meter. But you still need a load.

Putting an amp meter "across" a battery will accomplish nothing.
It must be placed in series with the battery and the load.

Edit: Beat again.

It doesn't. You need a load to measure current. Without a load you only measure potential.

I might happen to work in a specific electrical field.

It will tell you the max amperage output of the battery across whatever sense resistor is in the meter, and the internal resistance of the battery.

The thread title is explicitly "Can you use an electrical multi-meter to test CR123 batteries?" Answer: YES.

last question in the OP: "Could a person use a multimeter to check which ones put out more volts or amps?" Answer: YES.

An amp multimeter set to amps is a sub-ohm resistor and is one hell of a load for a small primary battery.

He's saying short-circuit the battery through the meter on current setting and if the ESR of the battery is high enough to avoid blowing the fuse you'll get an amperage reading.  Try that on anything with real juice and you're going to blow fuses or release smoke.  Not sure what that will test or really tell you about charge state but I'd imagine if the meter can handle 10A that's probably more than a CR123 can output.


Static voltage can probably give you a ball-park idea of charge state but if it's sat around a while that can be misleading.  Put even a small load on it and once the built up charge is depleted the battery sags.

Do any clamp meters measure DC current? Mine only does AC.

Yes

Exactly.

As far as what it will tell you about charge state, the internal resistance (impedance/ESR) of a primary battery is proportional to state of charge (given the same temperature and bunch of other variables, which you can dismiss if you're sorting a stack of the same cells.)

The lower the state of charge, the higher the ESR, and the lower the amperage will be measured.

This test will very quickly show state of charge among a group of batteries of the same type. And yes, not recommended for high amp batteries, I'd not advise this trick if you were trying to sort of a bunch of high-output lithium ion cells, for example, as they'd easily smoke the fuse.

Static charge used to work kind of OK on old carbon zinc cells, but sucks for most of today's chemistries.

So can I measure how many amps my house mains can supply if I set my Harbor Freight multimeter to amps, connect to amp inputs, and stick the probes into an electrical outlet?

Off to try this!





j/k

ETA:  The only real way to test a battery for quality is to connect to a programmable or fixed load and a voltmeter and time how long it can withstand a given current load before the voltage drops below some value.  On our quadcopters with LiPo packs, we connect to a 60A load and time how long it can supply current before dropping to 3.8VDC, then allowing the pack to recover, repeating until it stops recovering significantly.  Better packs = more seconds.  Of course this drains the battery but tells you if one brand is better than another.  Another way is to measure internal resistance of the battery.  Better packs have lower internal resistance and will be able to supply higher current for a longer period of time.

Goddamned phone a t e another detailed post.

You don't stick the probes in the outlet directly, you use a knife and your body as a resistor.

Did a quick test of a new Surefire 123A which was 3.08v on the Sears meter on the 9v battery setting and 3.258 on the Klein. I don't know any of the fancy test settings. Attached File

Since your living depends on you seeing, I recommend that spend some personal money upfront. I have one of these and I have 2 spare PETZL CORE batteries.

You can also power your PETZL ACTIK with 3-AAA batteries, these batteries have ~3x the rated amp-hour capacity of the PETZL CORE rechargeable batteries and also you will need a charger that can charge 3 at a time most AAA chargers can only 2 at a time.

PETZL, ACTIK CORE Headlamp, 450 Lumens, Rechargeable, with CORE Battery, Black

POWER MADE EASY: Includes our CORE battery that recharges in just 3 hours; With our HYBRID CONCEPT design, it’s also compatible with 3 AAA batteries for longer trips (not included)

Panasonic BK-4HCCA4BA eneloop pro AAA High Capacity Ni-MH Pre-Charged Rechargeable Batteries, Black , 4 Pack

I bought an Olight Perun headlamp and it's a bright mono, my next purchase will be the Freya for the colored output. Happy with the Perun but it's a pretty big light for headlamp use. Olights USB magnetic charging is first class. I bought spare batteries for several lights and haven't needed one yet in 2 years of daily use.

absolutely you can. fully charged or new, should measure 3.0-3.1V.

Depleted but still got some runtime on it: 2.5V. In devices that drain cells very little, like Aimpoint, you can get a lot of hours out of a 2.6V primary 123 battery.

Another thought is to use rechargeables.

Go stick your meter leads in your wall and see if you have 15 amps then, scooter.  I know you will try, some people think they know everything.

I specifically told my brother not to do this and why, when I gave him a meter.  I use to teach this class.  He did it anyway and the cheap meter was blown up pretty nicely. I recall it was an early digital Craftsman meter.

You need to add load to test a battery.  Sure you can test voltage and it will read the correct battery voltage, but that wont tell you if its good.

I use this

A wall outlet isn't a current-limited source like a CR123 battery is.

use an indicator or dome 12v auto light bulb as a load. it doesn't need to light up, just be a load over the voltage of the battery being tested

wire it up as

multimedia (+) -------- light bulb -------- (+) of battery (-) of battery -------- (-) of multimeter

put it on volts, and see how voltage is and how it drops under load

higher voltage compared to other batteries mean more charge
less voltage drop mean more capacity. idealy there should be little drop if there is a lot of capacity left

A better question is “what is a good reference load to use when testing a CR123”?  Measure voltage under load and compare to a new battery.

ETA it appears that some use high wattage resistors (5W 3 ohm) to test. That’s round about an ampere of current and some batts have been known to heat, swell, and even catch fire if they can’t sustain the output.

At that output, voltage sag should be easy to measure and correlate directly to remaining usefulness.  I buy new 123’s by the dozen every few years for lights and lasers. I’m going to order a couple hi watt resistors from Amazon to try.

Measure and watch for voltage drop over resistance.

Olight has some rechargeable CR123 and a pretty neat USB charging cord.

Red

Test under load.
Cr123 .5 amp spec
6 ohm 2 or more watt resistor will give full load to show how good or bad the cell is
Measure new cell and poor cell and make a chart based on voltage drop

I used to work with a guy who insisted that measuring a batteries unloaded voltage was a good way to measure if the battery was good.

I informed him that it was not valid. He said "well it gives you a pretty good idea of how good it is". ¯\_(?)_/¯ you can't explain these things to some people.

This is very wrong.

3.5v shorted is essentially 0 resistance, so essentially infinite amps(The physical ability of the battery to discharge at that point) That should blow the fuse on the meter, even at 3v.

Sighs.

In the early 90s as part of my job I worked with primary cell battery engineers at companies like Energizer and Duracell.
This stuff is not the rocket science some of you think it is.

Primary (non-rechargable) cell batteries such as AA and CR123A are not ideal power supplies and are not capable of sourcing infinite current.

Real world primary batteries typically have internal resistances in the hundreds of milliOhms, which defines the physical ability of the
battery to discharge and fundamentally limits total current they can provide to a few amperes. Additionally the amp meter measures
by looking at the voltage drop across its own low-Ohm resistor (often around 20-100 milliOhms), and the meter is fed by test leads
that also have resistance, all limiting maximum current.

Combined you will find that the total circuit impedance/resistance will be somewhere in the neighborhood of half an ohm,
limiting the amperage drawn for a CR123 battery to around 6A or so. I just tested a brand new SureFire CR123A and
it sourced 7.5A, rapidly dropping to 6A within a few seconds and indicating that the total internal resistance + multimeter
and leads is about 400 milliohms, about what would be expected.

It will not blow a 10A fuse. It should be safe to do this same kind of testing with any conventional 1.5V cell, and with
most conventional small 9V batteries, as all have resistances that will keep the current below 10A. It would be wise to
only pulse-test the batteries, as continued loads at this amperage combined with the power dissipation from the
internal resistance will cause them to heat if the load it made continuous.

I would not suggest doing the came thing with a high output 18650 cell, as the internal resistances of such cells are far
lower and the cells will easily source enough current to blow the multimeter fuse, but even here with appropriate test
equipment you will find the cells are current limited, albeit at much high levels of current.

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I didn’t know I was going to be opening a can of worms asking this question.



I bought some “CR123” rechargeables  but either they are dimensionally too small or the “electricity” they put out makes the headlamp LED  like “trip”.

Convince them to buy some 18650 rechargeables and move on. Only thing I use the CR123s for are in devices that won't take a rechargeable due to only using 1 battery.

As for life, load testing is good in a non-led light. When the light dims, they are almost dead

This is the internet, given enough time arguments will break out about whether the 7th or 8th slice of white bread tastes better.

Volts, yes, absolutely, I do that all the time.

Amps: The highest max rating of the amp meter in a dvom I have ever seen is 10A. Not sure what a 123 will put out (which means next to nothing).  I'm guessing the internal resistance spec on the battery might be a clue - you want lower resistance.

To get a viable reading you need to put the battery under a load similar to ordinary use.

Could one measure the resistance of the flashlight and get some number of Ohms…. Then buy the same Ohm resistor and put it in series with the battery to see how many amps it draws?

I was checking out this Steiner I bought a few years ago:

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And none of the old CR123’s I had, had enough “juice” to get the laser to turn on.

Argghhh..,,

As a side note, there is this thread on rechargeables:

https://www.ar15.com/forums/general/Tier-I-rechargeable-CR123-16340-batts-/5-2501433/?r=-1&page=1&anc=95627138#i95627138

I'm not addressing your question OP, but I will say that I work for an employer who issues shitty headlamps too. I picked up a Halo SL (link) about 2 years ago and would probably not do my job without it anymore. Well worth the investment.

To the conversation of dmm fuses - I commonly use a fluke 172 to measure shorts on a cable network usually around 25-30 amps. The trick is to only check for about a second and then take the lead off.