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I have a problem with any given breaker leaking a current to the frame of the body.

I have tested the pedestal of that the RV is connected to and there seems to be no problems there, with all connections. Ground to neutral produces no power.

Inside the RV on the other hand some of the outlets from ground to neutral are producing a current of 10V~.

I have tested each and every breaker and there is some amount of voltage leaking to the RV frame no matter which breaker is on. Some breakers leak a lot more current to the RV frame than others as show below:

Breaker Voltage
GFI 11.5V~
GEN/DISHWASHER 23V~
WASH/DRYER 1.6V~
MICRO 4V~
AC1 .6V~
FIREPLACE 2.9V~
AC2 1V~
WATERHEATER .3V~

These are all the current amounts when connecting the frame of the RV to the ground of earth outside. When a certain combination of breakers are on, the frame produces more current, such as the GFI, GEN/DISHWASHER, and MICRO. These together produce a current of 39V~, but when all the breakers are on it produces a current of 33V~.

With this information, what recommendations would you guys give in order to resolve the issue? I live in this RV fulltime, and I understand that this is an extremely dangerous environment to be in. I have contacted multiple electricians and I am not going to be able to get anyone to visit until next week due to being them being booked.

Any help is GREATLY appreciated!

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    What is your measuring device? A common DVM measuring voltage will give random useless garbage readings. Commented Apr 21, 2021 at 23:45
  • It’s a Kobalt pocket digital multi-meter. lowes.com/pd/Kobalt-Compact-Multimeter/5001783439 But I am getting shocked on the body of my RV, this is when I turned off all power and attempted to start diagnosing the issue. Commented Apr 21, 2021 at 23:50
  • I take it the dryer and range are both gas? Commented Apr 22, 2021 at 1:36
  • @ThreePhaseEel range is gas, dryer is not. Commented Apr 22, 2021 at 2:01
  • 1
    @displayThisName -- the dryer uses a 4-prong cord, right? Commented Apr 22, 2021 at 2:26

2 Answers 2

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This is serious business. When it happens with boats, it causes electrical drownings.

This is probably a grounding system problem, not the fault of any one appliance.

So comparing one appliance/branch circuit to another is pointless.

I gather that "all you have is a hammer", but trying to detect ground faults with a voltmeter isn't going to get you very far. The readings you've seen are nothing but phantom voltage, and are to be expected in any system. Trying to detect the problem with readings alone won't do a very good job, even if you were doing the right readings with the right tools.

There's no substitute for using the Mark 1 eyeball to look at the physical installation.

Grounding starts at the grounding rods. These are 8' long rods, typically 2 of them, driven into the earth. Or perhaps Ufer if one was poured with the RV pad or adjacent structure, or other valid alternatives. There must be at least one set of these at every building and every RV stand. Physically inspect to assure that those are present.

From there, the grounding electrode system (GES) contains a set of thick bare copper wires from the ground rods to the Main Panel for the entire site. This is the first disconnect switch past the utility's electric meter serving the site (not to be confused with any sub-meters at each RV stand that are only for internal billing at the RV site; those don't matter here). Physically inspect to see that the GES wires to the main service panel are present, continuous, and that the connections at each end are not corroded.

Inside that main panel, the main site grounding is established. The GES comes in and attaches to a "ground bar" containing many wires. In a main panel only, that can be the neutral bar and have neutral wires also, since there is to be a Neutral-Ground Equipotential Bond in the main panel only. That's important, but it's not part of your problem today - I'm just mentioning it so you're not surprised if you see neutral wires on the ground bar in the main panel only. So inspect that. Again look for corrosion or loose wires.

From the main panel, grounds are carried in Equipment Grounding Conductors (EGC) - the familiar bare or green wires that should be in all modern wiring throughout the site.

Often, with an RV, there will be a subpanel near the RV, often at the RV stand itself. There must be a dedicated ground wire (EGC) between the main panel and the subpanel. If there is not, it can cause problems like you describe. Inspect both the main and subpanel to assure that ground wire exists and is tight and not corroded.

Further, the subpanel needs its own Ground Rods/GES if it is not attached to the same building as the utility's meter/main panel. So inspect the ground rods and GES bare wires, as above.

The subpanel should have neutral and ground isolated from each other, since it is not the main panel.

From that panel, a Branch circuit then serves the RV supply receptacle. That branch circuits needs to have a ground wire (EGC). That means either

  • A 4-wire/4-prong 240V connection - RVs typically use a NEMA 14-50 plug.
  • A 3-wire/3-prong 120V connection - RVs typically use a NEMA "TT30" or sometimes NEMA 1-15 (normal household plug).

One serious blunder is to jury-rig a NEMA 10-type range or dryer connection, or an ungrounded 120V supply. This does not have a ground. It cannot do the essential task ground must do, of preventing "that thing" from happening. So inspect the cable and receptacle to assure it is a grounded type, and the ground is connected properly at both ends.

Almost finally, the *plug-and-cord going to the RV itself needs to have a ground wire (EGC) and that needs to be properly bonded to the RV chassis. So inspect that likewise.

Lastly, check your RV's subpanel if any to assure neutral and ground are separated. A second/undesired neutral-ground bond there can combine with other problems to make a real mess.

Wait. Grounding conductor and ground rods!!??

Yeah. They do at least 3 different jobs.

The grounding electrode at the meter/main disconnect assures that the hot and neutral wires are reasonably near actual earth (i.e. 120V above earth is OK, 2400V above earth is not OK). That covers the risk of a current leak inside the transformer, whose primary is 2400V typically. That's what the neutral-ground equipotential bond does, and it needs a GES.

The local subpanel or RV stand needs local ground rods because voltage gradients happen: that's when there's a difference in voltage across the land between two locations, say because a nearby house has a "lost neutral", or a transformer on a distant pole has a problem. If there is a 50 volt difference between the RV stand and the house, then relying on the ground rods at the house is going to put your RV 50 volts above the local earth. So the second set of local ground rods prevents that from happening.

But then why do we need a ground wire also? Isn't dirt the absolutely ideal conductor? LOL no. It's a lousy conductor, as you might expect. One common failure is a 'bolted' (high current) hot-ground fault. Now if the EGC is present back to the main panel, hundreds of amps will flow and result in an immediate trip of the breaker. However, if the EGC is omitted and left to the dirt to carry this current, hundreds of amps won't flow - tens will. This will not trip the breaker. It will absolutely overwhelm the grounding electrode's ability to keep voltage at sane levels, and will electrify the ground around the electrode. Which is another thing that will have the effects you report.

So, physically inspect all the systems mentioned above. 98% of the time, the problem will be apparent upon physical inspection. A hidden failure of a wire inside a cable is unusual, so don't look for that until all the inspectable stuff has been crossed off the list.

If the problem is yours, the above will probably expose it.

The above work will should eliminate the most dangerous part here -- the shocking. It will take care of external causes such as a voltage gradient caused by current leakage not from you. (if you read the "electric shock drowning" literature, you see they can be caused by the other guy's boat). Same applies here.

Or it may actually be your problem, in which cases the above repairs will probably move the problem. For instance correcting a missing EGC may allow hundreds of amps to flow, causing a faulty appliance to trip the breaker instead of continuously electrify the RV chassis. That's a good thing, though.

Other ways to hunt down the problem

All of the above work is safety-smart and you should do it on general principles, and it will surely cure the immediate problem of shocking. All of it is Code-required today, but an old installation might be "grandfathered" to the Code as it was written at the time. The local inspector respects grandfathering; the Grim Reaper does not.

Your best friend is the GFCI device. It comes as either a receptacle for 120V circuits, or a breaker for any kind of circuit. If the root problems are sourced from any of your equipment, it will certainly trip a GFCI. Putting the whole RV on a GFCI should put an end to the shocks, however it won't cure a "lack of local ground rods + voltage gradient" problem because GFCIs don't interrupt ground.

Next, once you have thoroughly checked out the above, you know you have good neutral-ground hygiene (i.e. separation). At this point, a problem in your own equipment should manifest as current flowing on the ground wire. There should never be any.

However, you cannot measure this with a voltmeter. You must use an ammeter, and fortunately it is AC power, so inductive/"clamp" ammeters are effective, which is a great deal less messy than DC current measurement!

You can amplify the sensitivity of the meter by clamping a coil of wire. If you make 1 loop and clamp the wire where it passes itself, you will measure 2x the current. If you make 9 loops and clamp it where it is 10x, you get 10x sensitivity, etc.

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They make static dissipaters fancy carbon fiber pieces that touch the ground when your step is down.

I provided a dollar fifty $1.50. solution for my customers. I attached some brass chain to the step so when the step was lowered the chain had a few links on the ground. It did take a screw to mount it in an existing hole and I made 2 for good measure but this was much less expensive than the carbon fiber rip-off for 30$ and my chain did not have a full 1year guarantee, and my chain did not have to be installed by an RV mechanic.

You may have gotten some static shocks but the voltages you list are not hazardous. Instead of calling someone that charges by the hour try the chain you just may save a C note or close.

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