Is this multimeter decent for checking battery voltage?

[jbviau]

Apologies in advance if this type of question is asked too often. I did search around a bit. If this thread is the equivalent of "Which LED drop-in should I buy for my 6P" in the LED forum, I'll be duly humiliated and go slinking off into the shadows.

Anyway, your pointers to helpful threads or, even better, to products would be greatly appreciated, as I have no real experience working with circuits, etc., and so have trouble comparing multimeters/battery testers.

*What I need*: A gadget that will check the voltage on my li-ion rechargeables, which include AW 17670s and 10440s.

I'm looking at this multimeter on Amazon:

http://www.amazon.com/dp/B000EVYGZA/?tag=cpf0b6-20

Is it up to the task? I gather that it will check a battery's voltage under load, which is desireable (could be wrong). Is it overkill?

I don't want to spend more than this, which rules out the nicer ZTS units. Cheaper would be better. I also don't want to buy a charger that *also* tests battery voltage, since the chargers I have now work fine.

Thanks!

 

[fxstsb]

Yes. Volt meters need a load to check load. Voltmeters themselves should have "No load" on their measurment device. The meter you have selected appears to have no specs but is probably as good as the next. If you have concern buy a Fluke or Simpson. What is more important is what are you going to use for a load and how are you going to perform the test. Just to keep it simple, just measure the battery and forget about the load. Look at the specs. Cuz, if you don't know what you are doing.....poof!

 

[jbviau]

Thanks for the reply.

I'm a little confused because from the picture of the multimeter I linked to it looks like you *have to* select a load in order to test batteries. The section of the dial labeled "battery load test" has options like 1.5v, 6v, etc., but no "no load" option. Are you suggesting I would turn the dial to a different section to test voltage? Or would I just set this to, say, 1.5v, put the red lead on the positive battery terminal and the black lead on the negative terminal, and see what reading I get? Feeling wary here. Don't want to go <poof> like you said!

Now that I think about it I'm a little worried by the description of this multimeter because it mentions green, yellow, and red LEDs for indicating voltage. What I want to know is the precise voltage that my battery is at when it comes off the charger, e.g. 4.21v for a 10440.

 

[Anders]

Hello jbviau.

Here you can read more about this meter:
http://www.autorepairmanuals.biz/site/573683/product/EQUUS3320


Anders

 

[coppertrail]

I believe the voltages within the battery section of the DMM are actually ranges. For example, if you want to test a 3V CR123A cell, you'd turn it to the 6V setting. For NiMH and Alkaline cells, you'd use the 1.5V setting, so on and so forth.

 

[Hitthespot]

What I want to know is the precise voltage that my battery is at when it comes off the charger, e.g. 4.21v for a 10440.

For this almost any volt meter will work. My old Micronta anolog meter below or My expensive Fluke True RMS meter. It doesn't really matter. Go to Radio Shack and buy the cheapest Digital Meter that measure DC voltage and your fine for what you will use it for. The one you are looking at will work fine.

Now if you want to measure the battery under load that is something different. The Meter you are looking at does not have a 3.7 volt setting for lithium ion batteries ( for measuring under load ) so I don't know that it will serve that function.

Edit: Now that I look at the meter a little closer I think the Battery portion of this meter is just a Good/Bad indicator to let you know if the battery is good. I'm not sure if it reads the voltage out while under load but it may.

Bill

 

[Zenster]

Multi-meters don't care whether a battery is under load or not when you measure the voltage.
However, in order to more accurately determine what the true charge left is in a battery, you need to put it under load when you measure it.

For people unsophisticated in this stuff, you can make things really easy by spending under $30 and getting a ZTS battery tester. It automatically puts a battery under load, and giving a charge reading within a 20% range is plenty accurate to check to see how much life your batteries have left.

http://www.thomasdistributing.com/zts-mini-mbt-battery-tester.htm

 

[MorePower]

For checking state of charge of lithium ion cells, you can (and should) measure the voltage without a load applied, so using something like the ZTS tester is not necessary or appropriate.

Please see this post by DM51 with a handy chart relating resting voltage (OCV) of lithium ion cells to their state of charge:
http://candlepowerforums.com/vb/showpost.php?p=2304719&postcount=9

The multimeter you linked to should work fine for this purpose.

 

[jbviau]

Thanks to all for weighing in! :thumbsup:

It definitely helped. I'll look for a deal on a multimeter similar to the one linked in my first post, new or used.

 

[lumenal]

Wal*Mart sells that exact same meter, in the auto parts aisle.

 

[Elliot]

Yes. I bought one in WalMart about 5 months ago. I think I paid between $15 and $20 dollars. The "regular" functions work very well and the voltage readings seem on the money. The battery check function is nothing special - just Ok, but I did not buy it for that purpose.

 

[fxstsb]

When you load a battery the voltage will begin to change. It will deacrese. Do not put anything other than a normal load on a LI. Using a lead acid battery as an example. If you put a Large variable resistor "carbon pile" across a battery and a meter across the same battery as the load increases The current increases and the voltage decreases after a time. As you increase the load the resistor will get hot. At some point you may get smoke and both current and voltage will decrease. If you do not understand Ohms law you should not test a battery.

 

[Lite_me]

Edit: Now that I look at the meter a little closer I think the Battery portion of this meter is just a Good/Bad indicator to let you know if the battery is good. I'm not sure if it reads the voltage out while under load but it may.

Bill

I have one of these and it does display the voltage when using the battery check mode. I don't know for sure but it appears to put the battery under an approximately 100ma load, I'd say. Just an educated guess.

It also has just a straight DC voltage check -no load, if you're not sure about that point.

It has a loud continuity signal, I like that.

I bought mine at Wal*Mart and am very happy with it.