On 02/14/2011 10:08 PM, Percival P. Cassidy wrote:
On 02/14/11 08:29 pm, philo wrote:

I'm looking for charger/maintainer -- either an off-the-shelf unit
or a
schematic so I can build my own -- suitable for a flooded deep-cycle
battery, either a pair of 6V "golf cart" batteries in series or a
Group
31.

snip

The link worked for me just now -- at least when I added the http://
ahead of it.

to float the battery you must stay reasonably below the gassing point or
there will be considerable water consumption...hydrogen and oxygen
production and heating.


OTOH: the nominal open circuit voltage of a fully charged lead acid
battery is 2.12 volts / cell or 12.7v for a 6 cell battery....

so anywhere from 13.1 - 13.8 volts would work for "floating".

Back in the old days when I started in the industry,
the settings on the chargers could drift a bit...so we'd try to keep
everything in the middle of the accepted range or about 13.5 volts


If the battery is going to be on float for an extended period of time...
though the water consumption is minimal...it still needs to be checked
periodically and topped off as needed (never fill a battery up into the
"neck" area...the water level should be a bit below it)

Finally...a few times a year the battery should be equalize charged to
avoid the possibility of sulfation. Usually 6 hours will suffice.
The battery should be brought up to 14.2 volts and allowed to rise to
approx 15 volts depending on the type of charger

The "Super PwrGate" claims to take care of all phases except equalizing
-- but only for Gel-Cell and AGM batteries. "No Spam" says that the
Iota/IQ system even does regular (weekly!) equalization charges.

I was hoping to find or build something cheaper that could serve as a
controller to make use of one of the power supplies I own already as the
power source.

"Perce"


I'd give one of your power supplies a try and see if it gives you an
acceptable float voltage...

If not, then one of the commercial ones would probably be a lot easier
than trying to build one yourself