Re: batteries cutoff

[LEE A HART <XURQ03A@PRODIGY.COM>]

Tariq,

A very simple circuit is to use a relay with a low voltage coil, a zener
diode, and a potentiometer, all in series across the battery. Adjust the
potentiometer so the relay drops out when the voltage falls to the desired thres
 hold.

For a 12v battery, try a relay with a 6v coil, a 9v zener diode, and
potentiometer with a resistance about equal to the relay's coil. This will
work with a relay that typically pulls in at 70%, and drops out at 20% of
rated voltage.

This circuit has hysteresis; as the voltage falls, the relay drops out at
10v, but won't pull back in until the voltage rises to 13v. So once it
drops out, you have to put it on charge at least a little while before it
pulls in.

Lee Hart                     If you would not be forgotten
4209 France Ave. N.          Soon as you are dead and rotten
Robbinsdale, MN 55422 USA    Either write things worth the reading
phone (612) 533-3226         Or do things worthy of the writing
e-mail XURQ03A@prodigy.com   (Ben Franklin, Poor Richard's Almanac)
Re: batteries cutoff