Short in my "new" 92 Sovereign

[dikku@mac.com]

I kept blowing fuses while the ac was on in the airstream so I was confused. Tonite I leaned up against the trailer and got an electric shock. I got out a voltmeter and measured 21 volts bleeding through most of the skin of the trailer. This went away of course when I unplugged the trailer. This seems unsafe to me.

Anyone have any ideas on how to approach this problem?

There is a new airstream dealer close to my house but I'm not sure of their expertise. I am less than 2 hours away from the factory.

I just bought this unit on ebay out of Lincoln, MA. and this problem was not disclosed.
Thanks,
dik

[53flyingcloud]

Originally Posted by dikku@mac.com

I kept blowing fuses while the ac was on in the airstream so I was confused. Tonite I leaned up against the trailer and got an electric shock. I got out a voltmeter and measured 21 volts bleeding through most of the skin of the trailer. This went away of course when I unplugged the trailer. This seems unsafe to me.
Anyone have any ideas on how to approach this problem?
There is a new airstream dealer close to my house but I'm not sure of their expertise. I am less than 2 hours away from the factory.
I just bought this unit on ebay out of Lincoln, MA. and this problem was not disclosed.
Thanks,
dik

dik,
Not sure if this will isolate the problem but..try unplugging your univolter from the ac line..Then,once more, hook-up your shore power, and see if you still have the 21 volts measured on the skin.
It's not normal for you to have this type of "floating ac"..
ciao
53FC

[TomW]

Standards may have changed between '67 & '92, but my Overlander's shell/frame is grounded to the ground wire on shore power. You can check your unit by removing the cover to the circuit breaker box, tracing where the shore power ground wire goes.

It will probably be electrically connected to the metal circuit breaker box which is in turn electrically connected to the frame/shell.

Verifiy your shore power line & plug are good, and verify the shore power itself has a good ground.

Tom

[jimmickle]

If unpluging the univolt doesn't resolve the problem, I would start at the beginning. Check to see if the wall plug has correct polarity and that it has a good ground. One of those inexpensive, plug-in, three light testers (which you should always use before pluging in at a campgroung anyway) should tell you if the plug is OK. The next step is to determine if the ground side of the input AC line is properly connected to ground of the trailer. If this checks OK, try the tester in all the outlets in the trailer. This might find the offending circuit. If resolving these don'f rectify the problem, check resistance from hot to ground at the input plug to the trailer. There has to be some conductivity to cause this unsafe condition. Start pulling fuses until you isolate the offending circuit, then check the wiring and outlets for that circuit. My bet is that you will find the problem before getting to the last step.

[59toaster]

Check the polarity of the shore power.

[dikku@mac.com]

Well I went through the trailer thoroughly today with my dad the electrician. Sure enough my electric cords had issues. Bad grounds, reversed polarity, bad karma. But when I corrected these still the same: Electric Airstream. Sounds like a good name for a band.
"My wife fell in love with an airstream, I saw the prices, was shocked
I fell in love with the airstreams so sexy they rocked
Paid for a ready to go airstream on ebay, bid locked
Got the airsteam home nothin but problems, electric shocked"

Interestingly I checked the hot wire on the airstream plug in the back with the aluminum skin and got an infinite resistance reading. I would think a short would have led to resistance approaching zero.
We checked the skin for the voltage leak with the 4 different circuits individually and it shows up in the main.
When I tested the skin today with a good ground it had 45 volts a/c max going through it. I wonder how that would affect a wet 2 year old. Scary.
I tested all the outlets with a 3 prong plug in tester and they all read good.
I'm not sure I know where the "univolt" is to test it.
I also found a half bare mouse chewed wire in the back at the box where the cord is converted to romex wire, but no evidence of a short.
Next step: Jackson Center 8-2-04 for a factory check up.
Thanks all,
dik

[thenewkid64]

Your univolt is likely under the stove. It is part of the brown panel that contains your fuses. The only way to turn off one of these is to find the breaker that runs it.

One of the things you may want to do is to pull the cover of the breaker box and check the wiring inside the box. Someone could have added a non-code wire to it. We had a forum member that this happened to. The wire was allowing some of the voltage to neutral side of the box and then to the skin.

We have also seen where shore power cords have been made incorrectly and been reverse wired. I would start at the panel since you found damage to the shore power cord.

Pull the shore power cord off the panel and look for shorts, from there. A cracked buss bar could also be making contact somehow. Lastly once you have the panel open and the shore power cord disconnected you can flip off all breakers and look for shorts from the hot side to ground at the panel, flip one breaker at a time. If a short shows up then you know that there is a screw through a wire somewhere in that circuit. You doing the troubleshooting will save a few $$ at Jackson center

[overlander63]

You also can turn off ALL your breakers, at the same time, and see if you still have voltage at the skin. If so, you have narrowed your problem down to the breaker box, and the wiring going in to it.
Good luck tracking it down.
Terry

[john hd]

on older breaker boxes there is a paper insulator that prevents the ends of the neutral wires from touching the box itself.

check it to see if one of the ends of the neutral (white) wires has pierced the insulating paper and is contacting ground. also check that the neutral block insulation is still intact.

with the trailer unplugged there should be no continuty between the ground wires and the neutral or hot lugs in the box.

this is your only protection fron energizing the skin of the trailer in the event of reverse polarity.

john

[overlander63]

Originally Posted by john hd

on older breaker boxes there is a paper insulator that prevents the ends of the neutral wires from touching the box itself.

check it to see if one of the ends of the neutral (white) wires has pierced the insulating paper and is contacting ground. also check that the neutral block insulation is still intact.

with the trailer unplugged there should be no continuty between the ground wires and the neutral or hot lugs in the box.

this is your only protection fron energizing the skin of the trailer in the event of reverse polarity.

john

John, my Grandmother had a Spartan that had that problem, knocked the electrician halfway across the yard. The solution at the time was to cut a piece of an old inner tube and wedge it between the fuse box and the side of the trailer.Not that this is code, but it worked. When we cleaned out the trailer after she passed away many years and a move to Florida later, the inner tube was still in place. Sometimes the simplest solutions are best.
Terry

[dikku@mac.com]

OK, I have solved the problem. Every circuit in my basement had a bad ground.

We tested the power cord on the trailer with a 500 volt DC "meggar" and found no leaks. We plugged in to a good 20 amp circuit and voila, no leaks of voltage.
My dad is a retired electrician.
We are still planning a trip to the factory for a full check of all systems and estimates for some repairs to dented panels and a new clear coat application.
Thanks all,
dik