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jluke · 04-20-2012, 06:06 AM

Yesterday I plugged my 1997 Damon into a wall outlet in my carport while I was doing some work. I knelt on the ground and leaned my forearm against the metal driver's step and could feel a destinct tingling in my arm. Alarmed I tried it again with the same result. Thinking it was a bad ground, I unplugged the cord and moved it to another outlet and the problem went away. Obviously I have a bad outlet and will address that, but do I also have a slight short somewhere in the rv or did I just become a better ground return than the return to the outlet?

blackf3504dr · 04-20-2012, 06:18 AM

I think you found the problem. The outlet most likely is not properly grounded and when you leaned against the step you acted as the ground. My son in law had the same thing happen to him when they borrowed our motor home and he used a non grounding extension cord (two prong), when he grabbed the door handle he got the tingle also... He switched to a grounded cord and no more problem.

jackrobinryan · 04-20-2012, 06:52 AM

I personally, would not stop my looking there.

Have you checked and retighened the connections at the transfer switch? And the AC breaker panel. These are know to come loose over time.

I would be trying to recreate the issue and then going thru my AC breaker panel, switching each one OFF individually, looking for a culprit.

A good friend's electrocution death years ago, while working under a car with a poorly grounded power tool, has always made me over cautious.

safe travels
jack

jluke · 04-20-2012, 07:41 AM

Thanks I will do that and let the membrs know what happened. Having A/C votage running through my body makes me nervous.

BCooke · 04-20-2012, 08:37 AM

If you have a meter. Check the outlet that you had plugged into. Hot to neutral, hot to ground, neutral to ground. You had a hot chassis, in theory your hot to neutral will read lower than your hot to ground.

vermilye · 04-20-2012, 09:10 AM

One easy way to determine if there is too much leakage to the chassis of your RV is to plug it into a GFCI receptacle. If it trips, you have a problem, and need to find the fault. It is frequently caused by a failed refer or water heater electric element, but could also be the converter, almost any appliance, or bad wiring.

While in theory there should not be any current between the chassis & ground, in the real world there will always be a small amount of inductive leakage to the chassis from your converter & some appliances. If it is under 5ma, it won't trip a GFCI and is considered acceptable. A good ground connection will carry most of the leakage and few will feel a "tickle" between the earth & the chassis.

If the ground connection is missing due to poorly wired connectors, a bad adapter, etc even a small amount of leakage (less than what will trip a GFCI) can be felt by many. Since the ground connection both prevents a shock to the earth & also is designed to carry enough current to trip a circuit breaker of fuse if there is a fault between the hot & ground (or chassis) it is critical that it be a good connection. With the exception when powering the RV from a portable generator that does not bond the neutral to ground, a inexpensive 3 lamp circuit tester is a good way to check that your RV has a good ground connection.

Skip426 · 04-20-2012, 11:06 AM

Quote:

Originally Posted by jluke

Yesterday I plugged my 1997 Damon into a wall outlet in my carport while I was doing some work. I knelt on the ground and leaned my forearm against the metal driver's step and could feel a destinct tingling in my arm. Alarmed I tried it again with the same result. Thinking it was a bad ground, I unplugged the cord and moved it to another outlet and the problem went away. Obviously I have a bad outlet and will address that, but do I also have a slight short somewhere in the rv or did I just become a better ground return than the return to the outlet?

When your checking/replacing your wall out-let, pay attention to polarity at the receptical . Correct hook up of white/black wires. A friend used a carport plug for years on his 5th and had no problem till he hooked up to his coach, and started blowing breakers, getting jolts.By all means check the coach grounds, as other posters have mentioned ,but start at the house .

EngineerMike · 04-20-2012, 11:45 AM

I'm guessing the polarity on the initial outlet is reversed. Some (idiots) think polarity is unimportant, so outlets and other circuits get wired backwards. It can matter a lot.
Your 15A cord-end-plug is polarized as is the receptacle face (fat blade, skinny blade). The screws (or plug-in-ports) on back of receptacle are also, but some assembler makes this connection manually in the field. Black wire should go to brass screw, white to silver screw, ground to green screw. Swap black & white, and most devices work fine, until.........

Simple example about polarity- screw base light bulb. The screw thread is the Neutral or white wire part on both bulb & socket, the little nipple buried inside the screw socket & at end of bulb base is the hot (black). The hot is physically isolated from a person when there is a bulb in the socket even part way (good design). Reverse black & white wires at the source, and now a person can put their fingers on the hot part of the socket, the thread (maybe) when they reach for the lamp switch and certainly when they change the bulb. Polarity matters.

So w/your coach, if there is an incidental connection of the neutral to chassis ground (true in most rigs), and you plug into a hot-neutral/grounded-hot (backwards wired) source, the otherwise isolated chassis is now a potential source of 120V and you are a potential source of ground. If there is no load on the cord from coach sufficient to pop the breaker at the source, there may be enough potential to kill you by grounding out the coach. Correct polarity matters.

BTW, its better to use a polarity tester than your body. Home Depot or Lowes, and for a few dollars more you can get one that tests GFCI outlets as well. Cheap insurance.