T&T: battery box blower tap

[Peter Bennett]

Friday, June 1, 2007, 4:51:38 AM, Capefearboat wrote:

Cac> Does anyone know how a multistage battery charger  determines how long to
Cac> charge batteries at higher voltages before ramping down  to trickle charge?

A multistage charger will charge at maximum current until its output
voltage reaches 14.4 volts (or so, depending on battery type and
temperature), then will reduce current to maintain that voltage until
the current drops to about 5% of the charger's rating, then will
reduce the voltage to float level.

Cac>  I
Cac> would like to tap off the charger for a low amperage,  12V, 3", ignition
Cac> protected, fused, inline blower to cool the battery  box and remove hydrogen while
Cac> the charger is operating. Is this a viable  alternative to a separate circuit?
Cac> Would this cause the charger to  overcharge the batteries? If the charger has
Cac> more than one tap for multiple  banks would I be better off putting the blower
Cac> on a separate tap or combining it  with a battery bank. 
 
I don't see any easy way to do what you want.  If you connect the fan
to an output terminal connected to a battery, it will always be
powered.

If you connect the fan to an otherwise unused output of a
multi-output charger, it will still be powered as long as the charger
is delivering some current to the batteries. However, there should be
no problem doing this with a "muffin fan", as used in computers and
other electronic equipment, as these are fairly quiet, and are
intended to run for continuously for long  periods.




-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Lien Hwa 28 (AKA Polaris 30) "Sea Spray"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca