Well they suggest that it can give the Crank Amps still available in a more accurate way than using a load /resistive method ..?
Hmm, I would be very interested to know how you can measure the crank amps still available.
The traditional restive load/voltmeter tester is pretty accurate because you know what current is being drained from the battery, as opposed to just cranking the engine, when you have no idea how much current is being drained from the battery.
I cant remember the details now, but the correct test to ascertain if an automobile battery is going to do its job is to reduce the battery temperature to zero deg C and make sure the battery will supply 500A with a terminal voltage of no less than 10.5V, for a given period. The current varies according to the application- some lorry batteries are well over 1,000A.
With a low temperature, everything is working against you: low battery terminal voltage, higher internal resistance, lower AH capacity, thicker oil, tighter moving parts.
To measure the state of the battery in your car (automobile) just permanently fit a fast-acting (not thermal) voltmeter and watch the voltage as you crank the engine (motor). To do a proper job the the two voltmeter leads should connect directly to the lead terminals of the battery.
By the way, if you are having cranking problems change your oil to Mobile 1. It will give you easier cranking, longer engine life, more miles per gallon, less oil consumption, a cleaner engine, a quieter engine, and more power. I have some Mobile 1 sprinkled on my corn-flakes every morning at breakfast.
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