Quickly took out the multimeter and was getting about 90v AC from frame to earth (just sticking the mm probe into the dirt).

Immediately unplugged the trailer, but did a couple more tests when it was safe to do so and confirmed the frame is hot...

An AC plug tester in the trailer outlets showed everything OK (though I don't know if a household outlet tester is ideal for testing a trailer receptacle?).

I am going to where I have it parked now and will start testing everything I can find, but wondering if anyone has any good tips where to start etc?  Typical sources etc?

I have a background in electrical/electronics so hope I can track it down myself, but I just don't know RV electrical too intimately (yet).  I'll bring it in if I can't find the definite source, but thinking:

1) Test on different AC source....could have been the campground electrical reversed

2) Hot water heating element is shorted  (I'll see if it heats while only on AC)

3) Neutral to ground shorts.

4) Worn/shorted wiring  (pull wiring off all the terminal blocks and test each one for shorts etc.)

Not sure where else to look....thoughts?

Edit:  Am considering replacing all the old breakers with GFI+AFCI breakers.  Would cost a few bucks, but certainly add protection I think...

Idea...powering up the trailer (and seeing if the skin goes hot again) and then shutting off each breaker one at a time to see if I can track down a shorted circuit.

Grant

I copied this link from the pod mods section. One of the admins has a bunch of resources linked in there. 

http://www.rpod-owners.com/forum_posts.asp?TID=4748&title=important-check-this-every-time-you-set-up

  I'll be heading back to it tomorrow, safely plugging it in and doing numerous tests to see what results.  Picked up a non-contact voltage sensor today so should be easier for quick testing than my trusty multimeter.  

Fun times.....

The national electric code requires there to be a bonding conductor connecting the chassis of an RV to the equipment grounding buss in the RV panel board. For the record, this is Article 551.56 (B) in the 2020 Code. If that is connected them you shouldn't have much voltage between earth and the chassis (but it can be more than mcarter's 2/3 volt especially in a RV park where the earth ground at the park service panel might be pretty far away). 

I'm practically never plugged into mains power so I've never verified that on my trailer. Well, guess what, I show an open  on my ohmmeter between the ground pin on my power inlet and the chassis. If you have this condition it is very easy to develop a high voltage between the chassis and earth ground, in fact typically you will have some voltage roughly midway between 0 and 120V depending on the actual resistance between the chassis and earth vs the chassis and the line voltage in your 120V circuits. 

So, I would check that first. Pull the cord and measure the resistance between each of the 3 pins and the frame of the trailer. The ground pin should be low resistance, the other two pins should show open. There should NOT be a connection at the trailer (or a the pedestal) between the neutral and equipment ground conductors. Those should only be connected at the park (or your home) service panel. 

My ground pin is open so now I've got to go back and find out why, presumably a terminal somewhere has corrosion on it....could be that's your problem too. 

Could not under any situation detect any hot skin voltage.  Nothing.  Took every test I could think of.  So, was thinking it was maybe the campground power...

Then tried out with the heating element test.  Nothing. Could not detect anything so removed it (see picture) and replaced it.  Was hoping all would be done after this...

 

...but as it is with my life...no such luck.  Drove me crazy after that point...was getting no power at the element terminal, but there was 120v at the switch.

Taking voltages at so many points I finally figured out behind the black rubber "reset" pad there are two sets of thermostats/high limit switches (or some other protection device).

They look look like this....the propane side is fine...but the AC side is fried.  The "wire" shown between the two terminals is cooked in half.

So...another part to order...but at least tracked it down....I think.

So, the "hot skin" problem still not 100% solved, but I can't seem to re-create it...so likely a combination of the water heater element and/or campground power...or both.

Will update when fixed once and for all...

....so, after replacing that with a new one, plugging in the trailer, I was getting heat...YEAHHH!   And still no detectable trace of any power going to the chassis.

So, after getting it all back put together, I go to turn it OFF, and guess what...the AC power switch in the water heater compartment also appears to have fused now....cannot turn it off...sheesh...what next.

So, turned it off at the breaker and have to replace that next...

Whatever cooked the element appears to have done a job on the entire water heater electrical system.

I would also still confirm that you have a good ground connection between the chassis and the ground pin in your power inlet. That is very important to assure safety. You don't want to be working on this stuff with the chassis hot. 

Just did another round of testing today (as I was at the trailer and replacing the AC electrical switch for the hot water heater which had fried during previous events).

I've still been unable to replicate any electrical fault since the original electrocution event and after replacing the heating element, thermostat, and switch.

Tested resistance from numerous AC electrical ground locations (ground plug on various AC plugs, inside and exterior, ground bar in fuse box, and copper ground wire coming from fuse panel.

In all locations, resistance from chassis to ground location was always under 1 ohm.  So, all I can really say is that other than blaming the camp ground voltage supply for an improper ground, my FIRST thing I'll be testing EVERY time I plug in the trailer is electricity on the chassis...

Picked up one of these to stay with the trailer at all times....

https://www.homedepot.ca/product/klein-tools-non-contact-voltage-tester/1000664603 - https://www.homedepot.ca/product/klein-tools-non-contact-voltage-tester/1000664603

Not sure if it is just me, but also seems to be a LOT of electrocution threads here lately?

Please call is shock. Electrocution is a fatal dose of electricity (electrical execution is where it comes from). What happens to most people is being shocked, but the risk of a fatal shock under certain circumstances does exist.

When I was at Fort Hood, we had one truck and shelter in particular that was bad. At night, I could see the electricity sparking between the ladder and the ground. This is even with things being grounded with a long copper grounding rod.

Seems like an unusual number of shock issues lately to me too, but it is a small sample size. 

i ohm is good. It seems like you are probably good to go now. Use either an RV circuit analyser or as a minimum an open ground detector anywhere you plug in. I've only used the non contact testers to identify hot wires in a bundle (because you don't need direct contact through the wire insulation) but they ought to work fine to detect a hot skin condition. Note that they only detect AC voltages, so you can't use them to determine if a wire in your 12V system is hot or not. 

The remaining puzzling thing to me is why the switch and thermostat assembly in your water heater failed. In theory the breaker in the trailer panel should have prevented that. Maybe you at one point encountered a campground wiring system where either the ground or neutral was hot which might bypass the breaker entirely? 

The non-contact detector seems to work really well at detecting anything hot, so should be a good first check tool.

Ummm... Do I detect just a little stereotyping of Appalachian Americans perhaps?  

I'd guess RV parks have existed in the West just as long as in the East. And I've seen some electrical work in places like Boulder Creek CA that would more than match any Eastern jury rigging. Most likely pot fueled workmanship rather than beer fueled....

But honestly I don't really know because i'm nearly always bonndocking.  I expect its probably safest to assume that one can run into poorly maintained campgrounds and other businesses anywhere. Trust, but verify as they say. 

About 15 or 20 years later, they replaced the homebuilt gate with a commercial one, but they never did re-do the wiring. Instead, they ran a trench about 30 feet to the new gate location.

About another 20 years go by, and one of the houses is doing a remodel. One of the contractors towing a trailer, cuts the corner short, and rips one of the gates, motor, and post completely out of the ground.

So they replaced the gate motors, but hey still didn't fix the original Rube Goldberg electrical box down where the original gate was some 45 years ago.

We got an electrician  to look at it, and he gave us a quote of $1000 to fix the wiring. We've decided to do it ourselves because the underground conduit runs right past one of the motors. All we really need to do is dig a short trench of about 2', and put a pedestal right next to the motor.

I picked up the outdoor breaker panel and unistrut that we're going to use a couple months ago. Now I just need to get a round tuit.

Don't know yet..