battery conductivity tester

Geo-TH,In

Well-known Member
I don't think many on YT have a conductivity tester or a clue what they are. They are not a load tester, they are not an ammeter, mine has clamp on leads. After measuring the battery's health, it will show CCA. Then you can go to the next mode and measure volts, so when you start the engine you can see if alternator is working, voltage will increase if it is, usually over 14v.

I have used voltmeters for 45 years. I yet to see a voltmeter that can measusure 100's of amps.

I don't leave homw without a conductivity tester in my truck. It's my first go to tool when an engine won't start.
conductivity tester
 
George, is this a store-bought device or one your home-brew contraptions?

I guess I don't understand the practical difference between load testing and measuring a battery's conductance (or internal resistance). In both cases you're measuring the voltage drop due to internal resistance, although conductance is in mhos and voltage drop is in volts.
 
A conductivity tester will immediately tell you if you have an open cell. I use both that and load testers before I condemn a battery.
 
Harbor freight has them in the $60 price class, on sale. I have one and it seems to be fairly accurate. My tire & battery dealer has one, that they use exclusively. Theirs is far more expensive, probably more durable, but mine seems to read pretty much the same.
 
Mornin Neighbor George, To my way of thinking I want a device that can measure/calculate the AMPS a battery can pump out FOR HOW LONG before VOLTAGE DROPS to a certain level. Battery labels may speak to Cold Cranking Amps CCA or Reserve Capacity or Amp Hours of energy storage. In my RV its how many Amp Hours of energy storage I have that matters most to me versus any CCA rating if I wanted an engine starting battery. In my current arsenal I have a hydrometer, a voltmeter, and an old school high current draw load tester but I don't have a battery "conductivity" tester but I'm NOT saying its not a good or bad tool, I just never had one.

This chart hasn't anything to do with any conductivity or load tester, just the static unloaded battery voltage versus charge state of a lead acid battery. A full charged flooded lead acid battery at rest unloaded should read 12.6 volts (six cells in series each 2.1 volt) but if it only reads 12.3 volts its almost 25% discharged


Temperature: 67 degrees Fahrenheit

Percent Hydrometer Unloaded
charge reading voltage

100 1.262 12.61
75 1.207 12.28
50 1.157 11.98
25 1.117 11.74
0 1.097 11.62

Keep warm yall

John T
 
Mark,
I think I proving my point, many don't have one, most don't have a clue what a conductivity tester is and what it can do. And they have an opinion that it won't work.
geo
link to my tester
 
Can you easily explain why it is better or different than a load tester that you clamp on and read before, during and after putting load to battery with switch? I am interested just do not understand sorry?
 
As I recall conductance is the reciprocal of resistance.....1/R in ohms. The unit of conductance is the "mho", ohm spelled backwards.

Hey, if you have something that works for you, go for it. If you don't go for it. If I were a resident where a lot of you guys reside you can bet I'd have every gadget I thought necessary for the survival of my loved ones, employees and self. Use the ones that work and chunk the ones that don't.
 
Hmmmmmmmmmmm?

I have yet to see where anyone has said that it won't work.

One needs to know the IR of a cranking battery to determine its cranking capacity. Whether you do this by measuring mhos or loaded voltage drip is of little concern to me.

Dean
 
OK, I see that the conductance tester doesn't need the battery to be fully charged, which is a YUGE advantage over a conventional load tester. (And it's conductANCE, not conductIVITY. Conductivity, like resistivity, is a property of a material. We measure resistance/conductance.)

So it seems what the conductance tester is doing is a low-level load test: Measure the open circuit voltage, apply a small load and read the battery voltage again. Load tester does basically the same thing, except with a full charge and under a heavier load. If we assume the battery's internal resistance doesn't change under load, both methods should give similar results.

Before the days of microprocessors and (in particular) cheap high-precision analog-to-digital converters, it would have been difficult to build a device like your conductance tester. Using mechanical gauges, a load tester is a simple device to make, so that's what we used. But I can see how the conductance tester is a better route to go, since it can test a battery regardless of its state of charge.
 
Only way I know to accurately test a battery is to put a load on it and see how long it takes it to discharge. Load, time, and discharged voltage will depend on the battery capacity and type.

That tester says it doesn't discharge the battery which tells me it's just a fancy volt meter with a built in calculator.
 
I don't get it. A 12 volt cranking battery has one job. To put out enough amps to power a starter motor and keep voltage above 9 volts.
A load tester simulates that event perfectly and measures amps and voltage. I doubt any "conductivity" tester can do the same real-world test.
 
Thanks George. This was great information and I appreciate the links. I likely will get one of those testers. Paul
 

Had a bad battery in a set of dual batteries on a diesel. Pep Boys kept load testing them and showing good.. BUt they were load testing them at 100 amps. Both would pass. The batteries need to rated higher and put out for longer, to get through the glow plug cycle and then still have enough energy left to spin the engine fast enough to start properly... or in my case, even spin the engine at all.

this was a case of a stupid manager, not knowing how to set up the load tester. A conductance tester would have show the battery not meeting the rating.. But I guess even he could not have understood a low rating did not work for this application.


load testing... must be able to vary the load or its not going show up a high resistance cell connector. So load testing at 100 amps and keeping the voltage meter in the green is a bust.. as was in my case. load testing at 200 amps would have clearly shown the problem. also load testing for short duration does not necessarily show up suflate problem. For vehicles that take longer crank times, this is a problem as well.
 

I for one know what they are and know they are not 100% accurate. They are for speed or to simplify the process. Speed is to move cars in and out of the service bay quickly, simplify is so anyone can use it.

So don't be supersized if you get a pass and after you come to the end of your road the battery was in fact bad.

In my search of ways to check a battery I ran across this " 3 Minute battery test"


http://www.shadetreemechanic.com/tsp_electricity_101.htm

WEll it looks like I missed out on that as well as it seams to be a old technique. I am going to add that to my test to get a handle on it. The best thing one can do is test all battery's including NEW to get a feel for it. It takes years of testing different battery's in different conditions/age to get comfortable with what ever you use. Me I am going to stay with what works a Load Tester.

If I were to tote a tool it would be one that would get it started.

https://www.amazon.com/Antigravity-...2697&sr=8-1&keywords=micro+start+xp10
 
I've used a Motorola battery tester since the late 70's.... basically a pre-digital version of what you have. Works well.

<img src = "http://www.chicagopartsnetwork.com/By-Location-/Chicago-/Rental-Building-Equiptment-/Motorola-electronic-battery-tester-imgpic.jpg">
 
I have a very low confidence level in those! On two occasions I've had batteries test good using one. Actually it was 4 occasions and 2 batteries.

I was having a no start condition on my 07 Chrysler T&C when setting for nearly a week at a time without being started. All the symptom of a bad battery, slow crank etc. I could charge it and all would be good, until it sat for 5-6 days, then it wouldn't start. Had it tested and results showed it to be OK, just needing charge. After the second test, I just replaced it. Problem gone!

Same indications on my old 97 F150. Same test. Same results. Same fix.

I did load test the Chrysler battery before changing it and it failed!
 
Bingo.

Not to say that modern, electronic battery testers are not useful, but only that they are not foolproof.

Like Hobo has said, such testers are designed to improve efficiency in the service department by quickly testing a battery in a commercial environment. They are also designed to be produced at low cost without the copper and carbon needed to produce a proper load tester. With these design goals in mind, they are commercially successful.

As you have learned, if one wants a truly foolproof method, simply crank the engine in real world conditions.

Dean
 
All the testing in the world don't replace brain cells. Went through this years ago at Autozone. The better half's battery was six month's old and failed. Picked her up and recharged the battery. Had it tested to be on the safe side. Worked perfectly for two weeks and then had to go kick her off again. Tested perfect again. Bull - I want a new battery. No - it tests good. I told the manager - fine, you take my wife's six month old battery and put it in your wifes car and put hers in my wifes car so you'll get the call when she gets stranded instead of me & I'll call it good. He scratched his head a second and then handed me a new battery. Battery's are just like capacitors in that aspect. You can test them until the cows come home and your testers will say they're good when your brain tells you they aren't. Yes I use my meter and load tester on something I know should be good but never on something at the end of it's life span.

Sometimes some folks get carried away with gadgets trying to prove something has a few weeks life left in it when common sense should tell them to just change it. JMO
 
1/R rather than R. 1/R = I/V. R = V/I. Nothing has changed. Just the way you look at it and more whistles and bells I guess. Can't comment as I don't have one, nor have I ever seen one so it's not my place to comment. Like I said, if you have one, and like it I'm happy for you. Anything that makes life easier (that's legal) I'm all for, especially as I move on past the ? century mark.
 
Seldom spend the time with a tester, as I have soooo many vehicles with batteries, that when one has a problem, I swap batteries with one that starts &amp; runs, then see if the problem stays with vehicle or moves with battery. I'm done.
 
Paul,
It's refreshing that someone can read and learn from a post.

Many here think this is a load tester, it isn't. Conductivity tester can also tell you when there is a dead cell too.

I gave away my load tester after buying this 6 years ago. No way can a load tester measure the condition of a 1200 cca battery.

No one has yet posted a way to actually measure a battery's ability to produce amps.

When this says a battery is shot, it's shot.

Take any battery to a auto parts place, a meter like mine what they are using and have used for years. Same with auto dealers selling new cars. Using a meter like mine is a part of most dealers 30 point inspection when you get car serviced.
geo
 
The reason I got rid of a load tester is because they can't measure the acutal amps a battery can produce.

Cheapie load testers might measure 100 amps. If your battery is worhtless and can't produce 100a, good chance it won't start a car either. I have a 1200 amp battery on dump trailer. Their isn't a load tester can stand up to 1200 amps, a conductivity tester measures the batteries ability to produce current and some how determine the condition of the cells.

Some People on YT don't comprehend how they work. I think the the conductivity tester has been in existance for 25 years or so.
geo
 
Nothing wrong with moving batteries. I know a man who has many
tractors and only one battery he rotates to different tractors.

There is an unwritten rule, your car will only break down when
it extremely cold, blowing snow, it's late at night on
christmas eve, you are driving out of town, it raining, late at
night, leave you stranded along an interstate. All the above
has happened to me.

I like to know ahead of time when my battery is going to take a
dump and replace it before. Save old batteries for a tractor or
something I won't get stranded with. Then I have about 6 dead
batteries sitting on a shelf to use as a core battery.

Same when it comes to tires and brakes, I replace them before
tire goes flat and brakes are putting groves in disk.

I've had my tester for about 6 years and will never be without.
I have about 20 lead acid batteries too.
geo
 
Mark, the first load testers I've seen measure each cell. Old batteires used to have a buss bar that connected each cell on the top of the battery.

Nothing is perfect, including the resistive testers which isn't much good is you have a 1200 amp battery and you are draining less than 10% of that through a load tester.

My 1200 amp battery showed good on a load tester and showed 600 amps on my tester.

geo
 
No arguement, the best load tester is the starter.

I use my tester to trouble shoot with. When nothing works, starter doesn't crank, I test the battery condition first. Measuring voltage will only tell me if I left something on and battery is drained. Just because you get a 12 v reading doesn't really mean anything. 12v when starter is working means you have an extremely healthy battery.

Any tester can be fooled. If you go to a store, they charge your battery. It may pass after charged. The real test is to test a battery days after you take it off charger. A battery with a dead or weak cell battery will lose charge. My tester can tell is you have a bad cell.

I think it's not fair to say I took my battery to town to be tested and some kind behind the counter that has no clue what he is doing tell you the battery is good. Best reason I know to have your own that you have used for years and know it reliable.
 
I have no experience with conductive testers but have read up on them a little. I understand they do have their place. The problem I have with this discussion is some are referring to a fixed load tester that is often used by store personnel to test a battery. I know, went through that with a couple of parts men. A true load tester has the capability to load the battery to the proper current draw for the size of the battery. A large capacity battery that is in poor condition can easily show 100 amp draw of a fixed load tester in the acceptable range. A good low capacity battery can very well show in the failed range. You have to match the load to the size of the battery to even get a clue if battery is good or bad. Modern lead acid batteries are usually tested at half of the cold cranking rating with acceptable voltage at different temperatures. And also, if your vehicle requires a specific current draw to operate properly, your battery has to be capable of meeting that requirement. Too small a battery you will always have low voltage during cranking. Oversize battery will be an insurance policy if needed or possibly just wasted material.
 
Thanks geo I counted up in farm equip alone we have 47 batteries on the farm. For just making sure if battery is is need of replace or not would you recommend this vs. Load tester i already have and what should I look for. Like reading yours and guidos posts on tool talk. Joe
 
We had 3 or 4 of those Midtronics at work, General Motors required them to warranty a battery, they had a failure code. Then about five years ago they sent out a big one on a 2 wheel cart that had to be run on every new car in the predelivery insp. and attach a print out to the repair order. That one wasn't too popular because sometimes it spent an hour analyzing and charging and reanalyzing before it spit out the report while tying up a stall.
 
Hello Geo-Th,In

WHAT! You have not seen a real battery load tester. Your 1000CCA battery can be loaded with this tester to let most of the smoke out permanently. READ the capacity 1000 AMPS. Associated model #6036B
available at wally world,

Guido.
a247750.jpg
 
Hello John T,

A battery tester needs to be able to test the battery for its intended use, period! LSI (LIGHTS START IGNITION)- automotive batteries are load tested at 1/2 the rated CCA for a very good reason. The automotive battery main function is to delivery a relatively large amount of power in the time that it takes the engine to start. It really does not matter how many hours can keep a light bulb lit without beeing charged. All other automotive loads,each draw less, and while the battery is maintaied at around 14Volts by the charging system. Testing an automotive battery for reserve power, its like going to the doctor and tell him that you run out of breath in a short fast running dash, and he puts you up on a threadill @ 1 M.P.H. to see how long it takes you to run out of breath!

Guido.
 
Hello MarkB_MI,

And a volt meter will measure the voltage drop while the engine is cranking or trying to crank. Seems like some people can't figure that one out. No load tester needed! It's under load already....MAN!

GUIDO.
 
regarding the 'not fair] comment: with this particular high end tester, operator error isn't possible. You attache the leads, push the buttons, and get a display readout and a printed report.

In addition, the test was done by a very good mechanic.

The only conclusion, IMNSHO, is that the tester is not infallible.
 
(quoted from post at 20:46:01 01/09/17) regarding the 'not fair] comment: with this particular high end tester, operator error isn't possible. You attache the leads, push the buttons, and get a display readout and a printed report.

In addition, the test was done by a very good mechanic.

The only conclusion, IMNSHO, is that the tester is not infallible.

Why would big parts stores get rid of a very good load tester.
Answer, warranty claims were to high it flagged a bad bat as it should were a conductance tester will pass it. I see it all the time not just on what I own its a PITA as you know to have to put up with a pass when its bad. I have sent a few folks back to the parts store for a refund on what they spent trying to resolve a bad bat a conductance tester passed.

If I were a major bat manufacture I would push conductance test to lower my return rate. Its a fact they will pass a battery that should be replaced there is no doubt but if you are into eye candy or something that will spit out a piece of paper that's the way to go.

A bat that fail's a load test but will hold 9.2V are more may last years who knows how long it with crank the engine that's were a conductance tester shines it will pass it. It does not cover up the fact the bat should be replaced its at the lower scale of its capacities.
 
Hello Hobo, NC,

I asked him to load test the battery that he claims the tester passed it @ 32 degrees F. With almost 100%
capacity, with his old carbon pe tester. Have not seen is reply. I know it will fail! I think you do too!

Guido.
 
(quoted from post at 22:52:32 01/10/17) Hello Hobo, NC,

I asked him to load test the battery that he claims the tester passed it @ 32 degrees F. With almost 100%
capacity, with his old carbon pe tester. Have not seen is reply. I know it will fail! I think you do too!

Guido.

Also no one has disputed my statement : A conductance tester will pass a bad battery: That in its self should be enough to chose a GOOD load tester over whistles and bells..

There is a art to load testing a bat that's the only advantage I can see with the whistle and bell machine. I have stated a bat that checks below 9.6 but not below 9V who knows how many times it will crank the engine before it leaves you dead in the water. The fact is, is its bad and not a calculated guess you get from a conductance tester.

If not for speed and convenience they would have never left the ground.
 
Yesterday's Tractor Forums

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top