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Harleydodge
06-11-2017, 05:23 PM
While out walking around our TH in bare feet this evening, I noticed that while touching the metal hinge on the rear door, there was a faint voltage present (I actually could feel a very slight electrical current flowing through me to ground) This was very slight and felt like only a few volts at low amperage.
Just wondering if this was normal and if anyone else has ever noticed this?

ctbruce
06-11-2017, 05:44 PM
That would not be normal. Are you plugged in to shore power?

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Harleydodge
06-11-2017, 05:48 PM
Yes...plugged into 15amp house plug via adaptors.
Unit is currently in our yard at home.
I will try unplugging and see if it's still an issue.

Harleydodge
06-11-2017, 05:59 PM
Update....just went out and checked, and I could not replicate the situation. I will have to investigate further.

JRTJH
06-11-2017, 06:05 PM
It sounds like your physical ground (the bare copper wire) is not connected "somewhere"... Possibly it vibrated loose in the trailer or you could have a loose connection "almost anywhere"... I'd be very cautious until you find the cause. My guess is the 15 amp circuit/plug at the house, but it could be anywhere in the entire circuit.

Harleydodge
06-20-2017, 06:03 PM
It sounds like your physical ground (the bare copper wire) is not connected "somewhere"... Possibly it vibrated loose in the trailer or you could have a loose connection "almost anywhere"... I'd be very cautious until you find the cause. My guess is the 15 amp circuit/plug at the house, but it could be anywhere in the entire circuit.

Thanks for the reply.
It got me thinking though.
How is a "physical ground" established if you happen to be dry camping and running off the Genny? I never thought about having to connect a ground rod of some sort.
This is not my current case (no pun intended :) ) but it just got me wondering.

JRTJH
06-20-2017, 06:51 PM
From what I understand, RVIA and most electrical codes stipulate that there can only be "one neutral/ground tie" in an electrical circuit. Hopefully there's an electrician that's more familiar with the codes that can expand on that.

Anyway, In trailers and generators, the physical ground and the neutral are not together. In homes they are tied together. Your trailer "can't be tied" because as soon as you plug it into the house or a campground pedestal, it would be "double tied" which is a violation of code. It's the same "theory" that is used with "double insulated" power tools (plastic case and separate connections for the neutral) which is why they no longer have a 3-prong power cord.

If your physical ground in the trailer is loose, corroded or otherwise not secure, you're relying only on your neutral to provide a return path for the 120 VAC wiring. If anything happens to interrupt the neutral half of the system, there's no "backup" to protect you against shock. When using a generator, if you have a "circuit protection device" on your trailer power cord, it will not allow power to pass to the trailer unless you use a "neutral/ground tie" at the generator. That "neutral/ground tie" physically connects the generator ground to the neutral bus. By doing that, you "create the same environment" as in your home wiring.

There's a lot of information about the differences in wiring and how they interact with each other in RV power. Some internet searching will provide you with more information than you'll ever want to read.

Suffice to say, there was "something" not working correctly if you got a "tingle" when touching the trailer while standing in damp grass.... Next time, it may be raining, you standing in wet sand with the trailer connected to a 50 amp campground power pedestal. That's not a good way to start (or end) a weekend camping trip.

Outback 325BH
06-20-2017, 07:57 PM
From what I understand, RVIA and most electrical codes stipulate that there can only be "one neutral/ground tie" in an electrical circuit. Hopefully there's an electrician that's more familiar with the codes that can expand on that.






The bonding of neutral and ground are allowed only once in a system because if there was a second (or more) bonding of the neutral and ground downstream, two things would result:
A parallel path would be created that would allow current to flow on the ground wire. In normal operations (no faults), no current flows on the ground. If more than one bond existed, the ground between the bondings would essentially be a second neutral and have current flowing on it. This is a safety problem and renders the purpose of the ground useless.
In addition, with current flowing on both the ground and neutral, it is possible to overload the ground wire since the ground does not have to be the same size as the neutral over a certain size. Current doesn't split across the two based on conductor size.

This is why it is critical to NOT bond in a house sub panel.

The main panel in your camper is just like a sub panel in your home (if you have one). All neutral and ground wires are isolated; the neutral/ground bonding occurs upstream-- probably in the pedestal.

If you look inside your main panel in your home, the neutral and ground are bonded there. That is why the neutrals and grounds are scattered and connected to the same buss... it doesn't matter. (Sometimes bonding is done in the meter and the main panel is kept not bonded. Less common though.)

The most technically correct way to use a generator would be to bond the neutral and ground in the genny, then ground the genny to a ground rod. Since that almost never happens, I think it is more acceptable to have the neutral and ground not bonded since the generator is not grounded. Of course we all know the floating ground issue with the EMS.



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Harleydodge
06-21-2017, 02:06 AM
Yes Thanks for both of your replies. It does seem the InterWeb is full of theories and conflicts as far as the "right" way to do it.

ctbruce
06-21-2017, 03:07 AM
Yes Thanks for both of your replies. It does seem the InterWeb is full of theories and conflicts as far as the "right" way to do it.
Like all things on the internet, I'd take some of them with a grain of salt and verify the resource. Due diligence is the battle cry.

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Harleydodge
06-29-2017, 06:23 PM
This issue has been resolved.
It was due to a disconnected ground wire in the receptacle I was plugged into in the Garage.

Thanks all for your input.

sourdough
06-30-2017, 07:12 AM
Yes Thanks for both of your replies. It does seem the InterWeb is full of theories and conflicts as far as the "right" way to do it.

I know the issue is resolved but just wanted to comment on the post above.

There really aren't any "theories" or conflicts any longer, as far as I know, on how electricity flows and the proper way to wire the various elements. There are established practices for them and not theories. There are many "arm chair" electricians that have their own ideas about stuff but not rooted in established practice. All of that to simply say to beware of random comments from folks on the internet. When dealing with electricity it could be a life or death choice. If in question, find the appropriate electrical code and go from there.....or get an electrician:)