12v solar pv charging 24v battery bank and vice-versa

renaultscenic2

I just want to know if a 12 volt solar pv connection can charge a 24v battery bank and also a 24v charging 12v battery bank

DConlyGuy

and mppt controller can use high voltage to charge a 12 volt battery easy enough, the other way 12volt to 24volt can be done but not really worth it

renaultscenic2

Ok thanks for the info

BB.

There are ways to do it as DC says, but it is usually not cost effective in most cases.

Do you have a specific application?

-Bill

vtmaps

Genasun makes some boost controllers that can charge a battery with a lower voltage solar panel. 

--vtMaps

renaultscenic2

The issue is I have 2 200watts panel connected in parallel,and I want to use a 24v inverter and I dont want to go on the roof to make a serial connection on the panels thats why im asking.

BB.

There are chargers/DC to DC converters that let you take energy from the "low 12 volt" string and use it to both charge and discharge the "high 12 volt" string of batteries. This is not "unusual" for use in buses and trucks (24 volt chassis, 12 volt "house power").

But these devices are not cheap (several hundred dollars or more?). Here is a smaller version that is capable of "balancing high and low 12 volt strings" and a "bus" balancer/equalizer:

12/24 Volt DC/DC 20 Amp DC-DC Converter ($230 from our host)
http://www.vanner.com/manuals/EQUALIZER-80CAN-SERIES.pdf

The Genasun controllers may work for your needs for ~$120 to $190)--Not sure (details matter--some more reading required):

http://genasun.com/products-store/mppt-solar-charge-controllers/mppt-for-lead-acid/

-Bill