Limiting battery drain by using what?

[joesimmers]

I recently built a small fan system to dry my wing tanks.

It is 12 volt and runs off of a 9 amp hour glider battery.

I thought that when the battery would get down to about 9 volts
that the fan would stop, this is not the case, the fan keeps working
till
the battery is down into the 5 volt range.

Is there something I can wire in that would make the system quit
working
when the battery reaches 9 or 10 volts so that I can get some more
life
out of my batteries?

Thanks for any advice,
Joe Simmers

[dlh...@charter.net]

Take a look at this:

http://www.safemart.com/Elk-Power-Supplies-Accessories/Elk-Low-Battery-Cutoff-Master-Power-Switch-ELK-965.htm

[Andy]

On Jul 23, 4:51 am, joesimmers <joesimm...@embarqmail.com> wrote:
> I recently built a small fan system to dry my wing tanks.

Even after the fan stops rotating it will still be drawing current and
the battery voltage can be expected to go to zero.

Simplest solution may be a timer. I think others have used solar
panels to power the dryer fan. If I was doing it I'd probably cobble
up a self latching relay. When the voltage drops low enough for the
relay to unlatch there is no battery load. You can tailor the drop
out voltage by selection of relay type and tweak it with a resistor in
series with the coil.

Andy