Strange connection from inverter to battery

[mikextr]

I have no idea why someone would wire their battery to the inverter like this. Take a look at these pictures. What problem do you think they were trying to solve? What should I do to correct it?

This is my first travel trailer and my first Airstream. It's a '67 Overlander that I am in the process of restoring. Spent most of yesterday hauling out the junk and cleaning it thoroughly. Now I'm ready to start the real work.

[idroba]

When it comes to electrical things on a 47 year old trailer who knows what previous owners (PO's) have done or why they did it.

The item you are referring to is a converter/charger, not an inverter. In Airstreams they were called the Univolt. In essence, they are obsolete and most owners simply re use them as a boat anchor and replace them with a modern 3 stage converter/charger which is far kinder on the batteries.

Have fun with your restoration. Always good to have them re done and back on the road.

[mikextr]

Thank you, idroba. If I have money left when I'm finished with the restoration I'll get a boat so this old Univolt doesn't go to waste

If I'm connected to an electrical hookup, will my trailer electrical systems work if I have removed the battery and converter (that's assuming the electrical system is otherwise wired properly)? I noticed that the converter is just plugged in to an outlet in the floor.

[idroba]

Waste not, want not. Your 120 volt outlets will work but all your lights, fans, and water pump use 12 volts, so they would not operate with the converter and battery missing. You can operate without the battery, just tape off the + leg which connects to the battery. This assumes the boat anchor is still operational.

Think of the money you will save when you buy your new boat. You can work a deal without an anchor as you already have one. If you need two or three, and will pay the shipping, I can send you more for free!

[mikextr]

You're so generous, idroba. I appreciate the offer and will keep it mind ;-)

Thanks for explaining the 120, converter, and battery relationship to me. That was very helpful. I've been hesitant to hook this trailer up to 120 because I did not understand the role of the converter and the mystery wire confused me. I'll test the converter and electrical system when I get back to work on my trailer tomorrow.

[idroba]

Unplug the converter/charger from the outlet on the floor. Tape the positive lead from the battery so it does not touch anything.

Plug the trailer into grid power. Turn all the 120 volt circuit breakers fully off, then back on to re set them in case any have turned off for some reason. Then your 120 volt outlets should all work, and maybe the AC unit if you have one. If there is a refrigerator, turn it on to "electric" (assuming it is a gas/electric one, of the original design) and in 4 to 8 hours it should be cold, at least in the freezer compartment. It will make no sound. It runs with a heater, not a compressor. If it is a newer refrigerator, it might require 12 volts to run, so the above test would not work without 12 volt power.

Plug your converter/charger in and you should have lights and fans and pump operation, even without a battery.

That will get you started at least.