Solar From Caravan to Tug

Vince · Senior Member

Solar From Caravan to Tug

Delta18 · Guru

I don't see why that couldn't be done but, to simplify things, why not just run the fridges from the van solar charged batteries from which the power you have should be ample.

I have fitted a solar panel to the roof of my ute canopy to charge the fridge battery in my tub.

Cheers Neil

Vince · Senior Member

Delta18 wrote:
I don't see why that couldn't be done but, to simplify things, why not just run the fridges from the van solar charged batteries from which the power you have should be ample.
Cheers Neil

That would be a simple way only the fridges in my vehicle are hard wired in, it just seems logical to power their source in my case.

I could get a separate portable folding solar panel and plug that in but with all the solar on the van I thought tapping into that will save buying and carrying the extra.

Thanks Neil

Cheers

Vince

Peter_n_Margaret · Guru

Your problem will be the voltage drop due to the distance from the solar source back to the tug batteries.
You will need either BIG cables and/or a DC-DC charger at the tug end, but that will waste power.

I can charge my crank battery from the solar on the OKA via a 2 way VSR near the crank battery, but the cables are VERY big and that is difficult with a caravan/tug.
Maybe run a new heavy cable and park in the closest position possible to keep the cable as short as possible?

Cheers,
Peter

03_Troopy · Guru

The way I do it isn't automatic, but it works for me:

In the vehicle
I have dual batteries in the vehicle charged via a Redarc SBI (Smart Battery Isolator)
I have 6B&S twin from the vehicles Auxiliary Battery back to an Anderson Plug on the rear of the vehicle to:
- a. Run the fridge
- b. Supply the DC-DC charger in the van for charging the van batteries while driving.
I also have another Anderson Plug at the front of the vehicle under the bonnet for running 12V accessories, also connected by 6B&S twin to the Auxilliary Battery.

In the van
2 X 105AH Deep Cycle batteries, Electroblock DC-DC and 240V charger (internally selected), 2 X 140W solar panels and Solar Controller

6B&S from the Anderson Plug at the tow hitch to a set of posts close to the battery compartment inside the van.
8B&S cable from the posts to the fridge via an ignition controlled relay.
8B&S cable from the posts to the DC-DC van battery charger.

6mm² from the DC-DC van charger to the batteries.
6mm² from the Solar Controller to the batteries via a 50A Anderson Plug pair.

When I need to use the solar to charge the vehicle batteries, I disconnect the Anderson plug from the solar regulator to the batteries, and using a 6B&S extension lead of about 3M, connect it to the front Anderson Plug on the vehicle.

Because the front Anderson plug is only connected to vehicle Aux Battery, I also need to press the "Start Assist Button" connected to the Redarc SBI which momentarily connects both Cranking and Aux batteries together, they will then stay connected while the input voltage (from the solar regulator) is above 12.7V

A 2 way SBI would overcome this extra step, but I fitted the one I have before the 2 way SBI was available.

This is not the ideal way to charge the batteries, because the solar reg is set up for deep cycle AGM batteries and the vehicle batteries are the flooded type. But because this is a very rare situation, and factoring a bit of voltage drop in the cables, I don't think it's that much of a worry.

Vince · Senior Member

Thank you for replies

03 Troopy I will copy what you have done as it seems what I was thinking of doing in the first place, but had to ask the question as written to see what responses came back.

again thanks for the responses

Cheers
Vince

Pamela G · Senior Member

smile hi Troopy my enquiry regarding your setup is your electro block dc dc just what is it - is it also solar regulator, and you mentioned your solar regulator what size is it. Your electro block dc dc is that in support of your solar regulator charging via 240 and solar

By the way it's Trevor not Pamela writing this.

We have 240w solar panels and 3 batteries deep cycle 105 amp hours that work ok in the tropics, however we are wanting to do the loop and think we need more power via another panel so will need to upgrade the 20a regulator (redarc) thinking about the DC Dc 40A We also want to charge back into the landcruiser auxillary battery so that we can keep a waco fridge going when needed.

Any thoughts would be appreciated. I have an Anderson plug on the back of the l/c to operate the boat loader but don't know its rating in amps we assume it's heavy as it handles the winch ok.

Thanks
Trevor biggrin