Cold cranking amperes (CCA) is the amount of current a battery can provide at 0 °F (−18 °C). The rating is defined as the current a lead-acid battery at that temperature can deliver for 30 seconds and maintain at least 1.2 volts per cell (7.2 volts for a 12-volt battery). It is a more demanding test than those at higher temperatures.
If a Boxster Battery is rated 600 CCA, that's the amount of amp it can deliver for 30 sec without draining itself..
A Battery Tester put a high load on a battery for 10-30 sec, and you look how the battery recover from that load..
look like the same specs for me.. from what I understand you should test a battery with the closest possible of it rated CCA to get a valuable result..
You want to know if you kill the battery with that test, and if you do, then it show you that the battery is not able to deliver those promises CCA anymore..
Testing a 800 CCA battery with a 150 Amp tester won't give much info about the true performance of the battery..
If a battery is supposed to be able to deliver me 800 CCA, it dosn't mean much to know that it can deliver 100 CCA :P
isn't just like asking a body builder to bench press 5 lbs?
(This is all from what I understand, I'm always open to learn better
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