[VAC] Re: Batteries

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Dick,
 I use a Milton Battery Load tester that I bought at my local autoparts
store a number of years ago. Looking at the JC Whitney Web Site
(http://www.jcwhitney.com), I found this one that looks much like mine:

http://www.jcwhitney.com/productnoitem.jhtml?CATID=5343, selling for
$45.99. They have a couple of others for $79.99 and $99.99.

These testers put a heavy load (100 amps or so) on the battery and have
a voltmeter to show the voltage drop under that stress. Although they're
meant to show the Cold Cranking Amps on a battery, that's a good
indication of the battery's state of health. I test the batteries on my
UPS (a pair of Group 27 RV/Marine wet batteries) monthly, along with the
starting battery on my genset, then record the readings. Doing the
recording allows me to track the health of the batteries over a period
of time and have plenty of warning when they're going bad. The "log
file" can be as simple as a PostIt Note stuck inside the battery
compartment door, and will pretty much elminate surprises.

                                       <<Jim>>