[eugenebrooks]

A tale of 7 batteries:

I finally got around to firing up the load tester on our batteries.
I list the results below:

Constant Load Current: 20.3 amps (checked with fluke current clamp)
Cutoff Votage: 11 volts

All of the batteries were charged with a
three stage battery charger just prior to testing.

The test is to record the time in "EDU main loop ticks"
that the battery takes to drop below 11 volts while under the
constant current load of 20.3 amps.

"Bat Num" Model Year "EDU Main loop ticks"
Battery 1 EX18-12 2006 77559
Battery 2 EX18-12 2005 62519
Battery 3 EX18-12 2005 35849
Battery 4 ES18-12 2004 79576
Battery 5 ES18-12 2005 82548
Battery 6 EX18-12 2006 95907
Battery 7 ES18-12 2004 109930

Battery 3 is one of the kit batteries from last year, as is battery 2.
The low performance of Battery 3 was double checked and a
second test produced 34377. This reflects the repeatability of
the measurement. It is unlikely that we would want to trust
Battery 3 for more than a single match before charging.

Battery 4 spent some time powering an electric fence
during the off season, which I think did it some harm.
It matched the capaciity of battery 7 when it was checked last year.

I have been digging for the time of an EDU main loop
clock tick, I remember it to be 0.0172 seconds, but
I have not found it in the legacy documentation yet.

2004 was, and still is, a very good year for batteries...