Auxiliary Battery For Refrigerator

Ken or Rotus,

Is the black negative wire running back to the auxiliary battery connected directly to the tow vehicle battery negative terminal?

Thanks,

Randy

 

I installed a large threaded insert into the vehicle frame (5/16 thread I think) and bolted a cable lug to it. My Xterra has a real frame (a dying breed) making a good ground path. If you can find an appropriate size bolt under there somewhere that is in the vehicle structure it should work fine to provide a ground.

Certainly running the wire back to the negative of the main battery is great, just uses more wire and a bit more work installing.

 

Thanks very much Rotus.

Am I correct is saying that there are no ground/negative wires that attach to either the breaker of isolator?

 

Is the breaker and isolator mounted directly to the frame? Doesn't it need to be grounded somehow?

 

The breaker has no ground, but the isolator has a small ground wire that must be connected to the body or frame (or battery negative if no other option is available). Other than that the mounting can be to anything. Mine are attached to my fuse panel cover.

 

Thanks everyone! Parts on order, I may reach out again. I think the biggest challenge will be running the wires back to the bed of my RAM truck.

Randy

 

Thanks Ken!

I did catch Rotus' note about grounding the isolator, thanks. That Rotus always give such good advice. No access to a lift so I will be doing some crawling, but I have air suspension on the truck so can get it pretty high off the ground. Did you enclose your wiring in any kind of cable housing?

 

Yup, Rotus has inspired several of my projects.....and I know what you mean about the getting older part, ha ha! Thanks!

 

Success! Thank you so much Rotus for the system design and Kenn & Peggy for the tips. I mounted the breaker and isolator on top of the fuse box and ran the wire back to the bed of the truck through some 3/4' flexible, outdoor conduit. Charges like a champ, showing 14.0V when the truck is running. One tip I picked up for crimping the connectors was to use a small sledge hammer and chisel, worked well.

I'll be able to easily pop the solar panel into the camper or the auxiliary battery, whichever needs topping off. What I like best is eliminating the heat build-up with the fridge in the galley while towing and being able to leave the fridge in the truck while in bear country.

 

This has been a great thread. I just reread all the posts. I want to do something different but along the same idea.

 

Gave my auxiliary battery its first test with three nights in Joshua Tree. Arrived fully charged (13.3) and the battery didn't dip below 12.5 the whole time running the Dometic in the back of the truck. Granted it was in the 30s at night but it got up to 60 during the day. Without the drain from the Dometic, the trailer battery lasted much longer without needing a solar top off. I like leaving my LED porch (running) lights and galley light on all night and that was no problem.

I did experience one problem. I tried to top off the auxiliary battery with my Zamp panel using a Zamp female plug to cigarette lighter male plug adaptor (sold by Zamp) inserted into the cigarette lighter female socket on the battery box. For whatever reason, the Zamp charge controller showed an error and wouldn't pass a charge. Not sure why, perhaps a bad plug? But, the good news is that I ran my truck for ten minutes and the battery went from 12.5 to 13.3, fully charged for this battery. It's shows a charging voltage of 14.1 when the truck is running.

All in all extremely pleased and I don't miss having to lift the fridge out of the galley or worry about it overheating in transit. I also really enjoyed having the empty side table to use for other purposes!

Thanks again Rotus!

Randy

 

[QUOTE=" I like leaving my LED porch (running) lights and galley light on all night and that was no problem.
[/QUOTE]

I must have missed this in orientation. How do you leave the LED running lights on while camping? I thought this only worked when trailering with the headlights on. Thanks. Ben

 

Ben,

On my trailer there are rocker switches right under the sidewall lights for turning on the running lights (we call them porch lights).

If you want to go with some super bright LED running lights, I highly recommend these bulbs:
Amazon.com: JDM ASTAR Extremely Bright 5730 SMD BA9 BA9S 53 57 1895 64111 LED Bulbs,Xenon White (Interior Use Only): Automotive

 

Hi Randy, Thanks. I think that feature is just for the 560. I use couple of different lights inside and outside my 550. I don't want to hijack this thread though. I'll have to create a separate post with pics. I need to get back out and take those pics - this winter keeps dragging on! Ben

 

Ben,

Making a "switch" to power the running lights when not connected to the tow vehicle would have to be done one of two ways. One would be to go into the wiring by the battery compartment and run wires from the brown running light wire to a switch and then to battery hot somewhere. Mount the switch somewhere in galley area. The other way would be much easier. This would be to take a vehicle side 7 pin socket and connect a jumper wire inside it from the black terminal to the brown terminal. Whenever you want to turn on your running lights at the campsite simply plug this socket onto the end of the 7 pin trailer cable.

Cary

 

Going off topic a bit... I picked up a couple of these a few years ago just at a local home improvement store. But similar to these: https://www.amazon.com/Solar-Lights-Motion-Sensor-Bright/dp/B075K8S6L6. A cord through the hole at the top, and I just hang them like porch lights, kind of draped over the roof of the 550 The ones I have are low light at night, and motion activated to a bright light.