Charging battery direct from alternator

There are several possible issues:

1. Voltage drop in the cable from the the alternator to the trailer leading to undercahrging of the trailer battery - large cable will reduce this.

2. Inadvertant discharging of your main battery - easily avoided if you disconnect the anderson plug when not travelling.

Friar,

The only problem I could see with this setup is that the charge from the alternator would be 'shared' between your vehicle's battery and the camper's battery. Neither would charge quickly. This probably wouldn't be a problem if you're doing a fair distance between camps.

Another option would be to fit an isolator to your vehicle's battery and then run the charge wire from this isolator to your anderson plug. With this setup your vehicle's battery will charge first, followed by the camper's batteries.

I've done this but from my vehicle's aux battery. So the charge sequence is main batteries (LC100 with 2 start batteries), then the aux battery to power the fridge, then the kamper batteries.

The other advantage of the isolator if when parked with the vehicle turned off the kamper won't drain power from the vehicle's battery. Although this can be over come by 'pulling the plug' between camper and vehicle.

My recommendation is to install an isolator such as a redarc in the car as well. It's a bit more money but well worth it.

As Tim said, you then will leave your car battery always fully charged.

I don't like parallel charging of batteries unless they are identical batteries which are also discharged in parallel.

Hi,

Redarc faxed me this the other day. Ring them if you want help. They really know what they're talking about.

Click the pic should enlarge it.

<img src="http://i163.photobucket.com/albums/t296/FizzF/redarcsetup.jpg"

That's a fairly simple system, Friar, but don't rely on "pulling the plug" on the trailer to isolate your main starting battery. I'll guarantee that one day, in a far away place, after a hard days driving, that you'll forget it - and bingo, bongo, bango - 2 flat batteries.

We've all done it. That's why we all use battery isolators such as Redarcs and Rotronics.

Bilbo - "The forgetful hobbit"