installing dual batteries and camp trailer battery

you realy have a range of options BUT understand there are no mirricles and ya alternator will only supply so much.

exactly how big are the batteries in question.

Ya starting to get into the bleeding edge where lots of people don't know but wont admit it....and realy there is a suck and see eliment.

The "safe option" that most people will recommend is to simply paralell the trailer battery up with the second battery in the vehicle.

this will work with either the existing redarc solenoid or with a funky charger.

The problem then is with the dc to dc charger you remove the realy advantageous 1 on 1 relationship the charger has with the battery.

realy want advantage do you think you will achieve with the dc to dc charger.

Remember there is an unavoidable limitation on how fast batteries will charge and a dc to dc charger will only improve that a little

I think the first port of call is to run with ya existing solenoid and paralell up the in car second battery and the trailer battery connection.

That has the additional benifit that you have an anderson plug outlet on the rear of the vehicle for connection of heavy drawing applinaces like inverters and compressors that comes straight off the second battery.

cheers

Hello Chad,
I'm about to install a second battery in the tub of my new Dual Cab BT-50.

I have already installed a DC-DC charger in the caravan to help make up for the over-distance voltage loss and to manage a portable solar panel. The caravan battery is wired in parallel with the car battery.

I intend to install a Redarc BCDC 1220IGN Smart Charger just ahead of the removeable tub battery. I'm toying with the idea of attaching it to the battery box. I anticipate that the 20 amp rating of the DC charger will allow the battery to easily achieve full charge. I could opt for a unit that will both charge the tub battery and manage a solar panel if I wished.

The tub installation will be via an 8 B&S cable - a spliced offtake - from the 6 B&S cable run direct from the engine battery to the 50 amp Anderson Plug at the tow bar.

The DC charger option is expensive, but if you consider that you're getting a 3 -stage battery charger, a battery isolator and maybe a solar panel regulator depending on the unit chosen - all in the one package, it becomes an attractive option.

My well-respected auto electrician has vetted my plan and seems impressed by it !

Cheers,
Netnut