12v - 12v charger

I currently charge the (hard to remove) batteries in my ASH-26E with a
solar panel and charger installed on/in my trailer. During a contest,
the plane may not spend much time in the trailer during daylight hours,
but it does spend most nights in there.

The solution would be to use the solar panel to charge a battery in the
trailer, which would then be used to charge the glider overnight. Best
would be to use this system all the time with two chargers in the
trailer and a single cable to hook up to the glider.

So... does anyone know of a charger that will accept 12v input to
charge a 12v/18ah SLA battery? I've found some charger chip
application notes, but I really don't want to build one of these.

Thanks,

-Tom

So... does anyone know of a charger that will accept 12v input to
charge a 12v/18ah SLA battery? I've found some charger chip
application notes, but I really don't want to build one of these.


Hi Tom,
the airplane model builders are using chargers with 12V input.
You best look in Google for a supplier of airplane model equipment
in your aerea.
Walter

http://www.hobby-lobby.com/chargers.htm

I recommend Graupner Ultramat 12
Regards
Udo



So... does anyone know of a charger that will accept 12v input to
charge a 12v/18ah SLA battery? I've found some charger chip
application notes, but I really don't want to build one of these.

Thanks,

-Tom

Udo Rumpf wrote:
http://www.hobby-lobby.com/chargers.htm

I recommend Graupner Ultramat 12

Thanks - that looks like the ticket. I had thought about RC model
chargers, but thought there might be issues using one on a lead acid
battery for prolonged trickle charging. The specs at the Graupner
website: http://shop.graupner.de/webuerp/servlet/AI?ARTN=6412.67 seem
to indicate this will not be a problem.

-Tom

check on http://www.strobl-solar.de who is specialised in Buffer
Batteries Systems

Regards

Mottley wrote:
check on http://www.strobl-solar.de who is specialised in Buffer
Batteries Systems

Very nice, but a bit outside my budget. The Graupner R/C charger is
looking like the best option so far. Now If I could find one with
fewer options - like just works for Lead-Acid the price might be even
better...

-Tom

T o d d P a t t i s t wrote:
snip

One option, if you want to keep your current 12 volt solar
cell system would be to buy a 12 volt DC to 120 volt AC
inverter and plug in a regular 12 volt charger. It's not
elegant or efficient, but it should work.

It depends very much on the particular inverter and charger, because
they are often marginally compatible; for example, I have a 300 watt
inverter that powers my 1 amp charger to about half output. So, test
before you buy an inverter, if you can.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Tom:
Even though my entire house runs that way, I wouldn't recommend
inverting and using a standard 120V charger. Eric points out that it's
not efficient. Better to do that in a larger system (the home is 1260W
solar, 400W wind, 48V grid tie inverter and battery backup, about 95%
efficient).
For someone with a hangar, use PV and a grid-tie inverter to run the
meter backwards during the daytime. Then plug your normal charger into
120V. This may or may not be "legal" where you live.
I've just started aquiring bits for a similar system. Perhaps with a
big enough "trailer" battery (less voltage drop as you charge the
glider) you could use two of the same charge controllers, one for the
trailer battery, one for the glider battery.

PV Panel - Solar Charge Controller - Trailer Battery - SCC - Glider
Battery.

There are solar charge controllers for around $40. But their weak
point will be whether the controller can deal with only 13-ish volts on
the supply side. PV panels generate well above their rated 12V. The 48V
array at home puts out about 100V open circuit! For an extra $50, the
model charge controllers like Udo pointed you to will work great.
There's another DC to DC model charger I've seen for $75 US. It will
do Sealed Lead Acid.
http://www.modelflight.com.au/rc_mod...ry_charger.htm
But it's in Australia.

It's great to get our electric power from the sun. Like centering a
nice thermal.
Jim

Check out

http://www.solarconverters.com/

they make, or will custom make, pretty much any DC to DC converter. They
also make stock MPPT solar charge controllers that are small in size, so
suitable for use in gliders with solar panels. An MPPT controller can gain
as much as 30% more battery charge current from a given PV panel.

all the best,

bumper
Minden, NV
"JS" wrote in message
oups.com...
Tom:
Even though my entire house runs that way, I wouldn't recommend
inverting and using a standard 120V charger. Eric points out that it's
not efficient. Better to do that in a larger system (the home is 1260W
solar, 400W wind, 48V grid tie inverter and battery backup, about 95%
efficient).
For someone with a hangar, use PV and a grid-tie inverter to run the
meter backwards during the daytime. Then plug your normal charger into
120V. This may or may not be "legal" where you live.
I've just started aquiring bits for a similar system. Perhaps with a
big enough "trailer" battery (less voltage drop as you charge the
glider) you could use two of the same charge controllers, one for the
trailer battery, one for the glider battery.

PV Panel - Solar Charge Controller - Trailer Battery - SCC - Glider
Battery.

There are solar charge controllers for around $40. But their weak
point will be whether the controller can deal with only 13-ish volts on
the supply side. PV panels generate well above their rated 12V. The 48V
array at home puts out about 100V open circuit! For an extra $50, the
model charge controllers like Udo pointed you to will work great.
There's another DC to DC model charger I've seen for $75 US. It will
do Sealed Lead Acid.
http://www.modelflight.com.au/rc_mod...ry_charger.htm
But it's in Australia.

It's great to get our electric power from the sun. Like centering a
nice thermal.
Jim

bumper wrote:

An MPPT controller can gain
as much as 30% more battery charge current from a given PV panel.


Their 3W MPPT controller is only 70 bucks. A good deal.