On Thu, 26 Jul 2007 10:23:19 -0700, Pete C
wrote:

On Jul 26, 4:29 pm, Stephen Trapani wrote:
Can't a person extrapolate state of charge with a simple voltmeter?

Good point, you can, with a few caveats which are covered by the
battery FAQ I posted a link to.

I'd probably use the voltmeter as a rough and ready guide on a day to
day basis, and a hydro now and then to verify it.

Cross referring the two could be pretty useful.

This is a wireless SG sensor setup.
Data can be fed to a PDA, laptop or desktop and crunched
by the relevant software for analysis.
http://www.electrosense.com.au/SG-Electrode.htm
Toss out those old hydrometers.
You can probably get a nice setup of these for less than $10k.
Agitator beds for the batteries could be added if desired, but
I haven't looked for them. If I ordered any of this stuff I would
want a couple pocket protectors thrown in gratis.

--Vic