charging 12 battery with 24 volt alternator

Hi Cruznoz, Yes it can be done various ways ,but what I have done is install a Redarc BMS ,battery management system, not cheap but it will take 24V and charge 12Volt batteries also will do solar and 240Volt without any thing to do ,it will decide what is the best charging medium and automatically do it ,it also has MPPT for solar ,I have one in my caravan ,and also fitted one in the Motorhome I built which had 24 Volt in and charged 2x 130ah AGM batteries .They are about $1795 from Redarc but on evil bay I got my last one for $980 .They have a new model out which is a 40Amp at about $1900 ,whereas the old one was 15Amp.It does the same as a dc-dc charger but with 240 V as well.
Regards John

Hi Cruznoz,

Any of the Redarc BCDC charger series will accept up to 32 volt input and deliver a staged 12 volts output to a battery. This series are less expensive than the BMS series but with less features, although possibly adequate for your application.

The Redarc BCDC series can be viewed here.

Couple of cheaper alternatives.....
1. Connect a 24V-240V inverter and use it to drive a 12V battery charger.
2. Fit a second alternator (12V) tuned to a decent charge voltage.

In both cases, add as much solar as possible.

Cheers,
Peter
OKA196 Motorhome

Thanks for the reply's everyone. The BCDC series that Allan suggested sounds like what I am looking for. Thanks again.

I have fitted the redarc BCDC (40amp) to my Isuzu 300 4x4 (24V) to give me 12v house battery's (2 x 110amp) & its works & charges well & an easy fit, I have also fitted the BCDC 24 to 24volt charger & its been un reliable & just stops working, have fitted 2 now & the 2nd one has stopped working now again for no reason
good luck

Jaycar have a suitable 24-> 12 volt charger. Installed into my mates old Toyota bus about 12 months ago. Have since added a low volt cutout