Maximum amps for testing AGM capacity?
After a winter of being very sick, and a spring of catching up on farm chores, I am finally back to being able to work on the van at least once in a blue moon. Next step, testing the 100aH Fiamm telec...
Forum Discussion
Discharge voltage and SG per SOC is fairly linear unlike recharging, so it is "good enough" for the first 10 hours though.
That article PT linked elsewhere about "partial tests" made the point that it is not so linear, so you had to do all 20 hours, for real accuracy, but I have done many 10 hour runs with Wet 12s and 6s and 12v AGMs and the numbers come out right, including when cross-checking SG, voltage, and AH count.
I did see that a 5 hour test to 75% is not so good. I think the reason is not linearity, but that the measuring tools' margins of error are too much for such a short time run.
BTW, I don't know if they mean to drop to 10.5 loaded in 20 hrs or if the 10.5 is after bounce back. If the load is by inverter, you can't get that low before the inverter quits from low voltage anyway.
That article PT linked elsewhere about "partial tests" made the point that it is not so linear, so you had to do all 20 hours, for real accuracy, but I have done many 10 hour runs with Wet 12s and 6s and 12v AGMs and the numbers come out right, including when cross-checking SG, voltage, and AH count.
I did see that a 5 hour test to 75% is not so good. I think the reason is not linearity, but that the measuring tools' margins of error are too much for such a short time run.
BTW, I don't know if they mean to drop to 10.5 loaded in 20 hrs or if the 10.5 is after bounce back. If the load is by inverter, you can't get that low before the inverter quits from low voltage anyway.
