testing lead/acid batteries.... electronic tester vs load tester

cy

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with winter sitting in all over the US.... there's got to be dying car batteries all over.
much better to catch a battery on the way out and replace ahead of time....instead of getting stuck.
hence the question:

testing lead-acid batteries.... electronic tester vs traditional load tester.... which is better?

Electronic lead/acid testers have been available for quiet some time. depending upon features of tester ...will test for bad cells, number of cold cranking amps, surface charge condition, etc. will give digital readout of condition.... one drawback is temperate of cell can distort readings... if tester doesn't have a feature to compensate for temps. tester will give false readings.

vs a traditional load tester hooks up battery to a mondo sized resister. which of course mimics the 300+ amps a starter motor can place on a battery. load test is quite simple... if battery can sustain load.. it passes

then let's factor in AGM cells... charging systems... corrosion on battery clamps... etc.

so which is better?

Electronic tester vs load tester

for test mules, got a Cornwell KA-8300 electronic tester made by SPX, Schumacher Speedtest and an ancient battery load tester with big honking resister coils in parallel.
 
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SilverFox

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Hello Cy,

The electronic testers have been greatly improved since their first introduction. They are basically looking at internal resistance of the the battery under different load conditions and at rest. However, the latest ones are not incorporating a load test into their evaluation.

This would indicate that you need both... :)

Keep in mind that temperature corrected resting voltage will give you some idea of what is going on, and every time you start your car you do a load test. If you monitor the voltage during starting, you will have an indication of load test results.

I have found that electronic testers work best when there is enough information to establish a trend line. If you do a test when the battery is new, you now have base line information. As your battery wears out, electronic testing can track this and give you an early indication of problems. For example when your calculated CCA value drops to 25 - 50% of its initial value, you may not get another winter out of your battery.

I monitor resting voltage, and voltage while starting, and have had very few surprises, however, I have been looking at this electronic monitor with interest.

Tom
 

Turak

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The electronic testers have been greatly improved since their first introduction. They are basically looking at internal resistance of the the battery under different load conditions and at rest. However, the latest ones are not incorporating a load test into their evaluation.

Tom

A minor correction.....I know it may be nit-picking a bit, but.....

The electronic testers for Lead-Acid batteries/Gel Cells/AGM Cells are usually looking at the 'impedence or sometimes the capacitance'....NOT the resistance.

While they may seem the same when it comes to batteries, technically there is quite a bit of difference.

I have not seen any electronic, hand held testers for Lead Acid batteries that is capable of actually measuring the true resistance. All of the testers I have seen measure the impedence and then extrapolate the quality of the battery based on the voltage, impedence, vDrop .vs/over a certain time period.

That's a nifty little monitor......does much more than the typical LED monitors I have seen. The fact it is LCD makes me wonder about the ruggedness of it. I have dealt with ALOT of LCD electronic equipment (i.e. meters, switches, etc.)....they rarely seem to hold up as well as some of their mechanical equivalents when it comes to harsh environments.
 
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65535

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Measuring the voltage drop when hooked up to a load tester works for me. If it maintains a high enough voltage I feel reasonably sure it'll do well enough for the road. Now if it doesn't yes I would replace it.
 

kramer5150

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A minor correction.....I know it may be nit-picking a bit, but.....

The electronic testers for Lead-Acid batteries/Gel Cells/AGM Cells are usually looking at the 'impedence or sometimes the capacitance'....NOT the resistance.

While they may seem the same when it comes to batteries, technically there is quite a bit of difference.

I have not seen any electronic, hand held testers for Lead Acid batteries that is capable of actually measuring the true resistance. All of the testers I have seen measure the impedence and then extrapolate the quality of the battery based on the voltage, impedence, vDrop .vs/over a certain time period.

That's a nifty little monitor......does much more than the typical LED monitors I have seen. The fact it is LCD makes me wonder about the ruggedness of it. I have dealt with ALOT of LCD electronic equipment (i.e. meters, switches, etc.)....they rarely seem to hold up as well as some of their mechanical equivalents when it comes to harsh environments.

You can measure the impedance of a DC component? For some reason I was always under the impression that its only for AC.

informative thread... thanks all!
 

Mr Happy

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You can measure the impedance of a DC component? For some reason I was always under the impression that its only for AC.

informative thread... thanks all!
Yes, you can pass AC through a component that normally handles DC. For an ideal resistor the AC impedance is the same as the DC resistance for all AC frequencies. However, due to the way the chemical reactions work in a battery the AC impedance will be different from the DC resistance.
 
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