75 sovereign electrical issues

[Pilebutt]

Hi,
I just purchased a 75 sovereign and am trying to get it ready for some use this winter. It has been sitting in a field for about 8 years and has some issues. I plugged it into the house when I got home and started running everything in the trailer including the AC. All the interior lights worked. fridge, and the AC was blowing cold! This is where things went sideways. The 30A cord was plugged into the house via an old crappy adapter. Adapter melted and smoked the GFI on the house. The next day I replaced the GFI and adapter. After plugging the cord back into the house I found that none of the 12V system was working. No lights, fans, nada. I can hear the Univolt humming but nothing works. I checked all the fuses and they seem to be in good repair. I have ordered a multi-meter to do some testing. Is it the Univolt?
I feel like it should be replaced anyway... Which converter should I buy? 45A? Do I need to replace the fuse panel as well if I replace the converter?
Any help would be appreciated!

[Belegedhel]

Welcome to the Forums!

The first thing you should do is look for a shop manual for your year of trailer. I found one one eBay for my '73, but there are several other sources for "official" reproductions. The shop manual will show wiring diagrams for your 12V, 120V, and tow vehicle umbilical wiring, which I have found to be pretty handy.

You don't want to try and run your airconditioner off of a typical household outlet (15A). Frankly, I am surprised that a breaker didn't trip before you melted your outlet--this may suggest that you have too large of a breaker on that circuit, and you might have ruined wiring in your walls, and have a potential fire waiting to happen. Most everything else in the trailer can be run using the adapter and household outlet, just don't turn everything on at once.

The Univolt is an antiquated piece of hardware. They are noisy and have a tendancy to boil batteries. Call Randy at Bestconverter.com, and he will be able to give you guideance and a fair deal on a new converter.

The univolt is also designed to be used in combination with a battery. If used without the battery, it will still produce 12V, but rumor has it, that using one without a battery precipitates failure--this might be your problem. Having a meter will definitely help you to troubleshoot.

If your 12V fuse panel is built into the univolt, then yes, you will have to replace your fuse panel when you replace the converter. If your fuse panel is separate, then it is up to you. Personnally, I would replace it just to be able to go with a more modern, automotive style fuse, rather than those old glass ones.

Good luck!

[Eagle & Bear]

Yes to all of the above. You do not need to be a licensed electrician. In our '76 the wiring schematic will be the same as yours. Black (+) positive or hot connects to the brass colored terminal, white (-) is neutral or negative and connects to silver terminal. Green is ground. Every time you want to work on the electrical system just make sure that you are not plugged into any power source.

Get a Sperry plug in from a hardware store. It a small yellow device with three colored lenses on one end and a (+ - grnd) plug on the other. When you finish it will tell you if your wiring job is good. There may be a clear lens near the HW heater that will light up if the pos and neg are reversed. If there is a reversal of the hot and neutral the Sperry will let you know which leg needs to be checked.

The Univolt is about 30#. Most of it is copper. Mine was beginning to tear apart its support under the oven. I do not know if there are any purists around but they may want to restore it and use it one of their rigs. Otherwise the copper is recyclable and it may help pay for a new converter.

What makes this job most desirable is that you can upgrade and expand your 110V service inside your AS. In the '70s folks did not have all of the gadgets we take for granted in the 21st century. The two 20 amp breakers can be replaced with four slims. You can run flex tubing that houses 3 - 12ga copper wire Romex. Run the flex through the walls and storage bins. Replace the 30 amp main breaker and the 15 amp GFI breaker just for good measure. You won't have to worry about them when you hit the road.

I have had several 30amp shore power plug failures - even the factory sealed 30amp plugs. if there are any signs of over heating of the plug, terminals or insulation they should be replaced. Carry both male and female plug and receptacles. Also look for any blackened receptacles. Replace as needed.

At some time in the future you will find yourself in an RV park with either faulty 30amp receptacles or breakers. You may also experience a surge or brown out from a system that was built 60 years ago. Just make sure your computer is protected by a back up battery.

Home Depot or Lowes have been stocking parts for RVs. With the exception of the converter all of the parts and material can be bought at a hardware store. RV shops will charge 2X to 3X what a hardware store will. Just draw out a schematic and create a parts list.

[Pilebutt]

Thank you both for your input. Volt meter should be delivered today so that I can investigate further. I found a manual with the wire diagrams. It will be a huge help. Something that has me stumped is that I thought the 12v lights would run off the new battery I installed without being plugged into 110. Fuses all look ok.

[Pilebutt]

Update. Tested the univolt. Less than 1v output. I removed it from the system and hooked up the battery. Had to clean the connections on the in line fuse from the main battery cable. 12v system is now working. Ordered a WFCO 55 converter and am hoping I will be good to go. Strongly thinking about replacing the fuse panel with a modern version.