RV Electricity – Hot grounds and the Stray Voltage Patrol

Dear Mike & Chuck,
My wife and I love reading your newsletter – keep up the good work! I just finished reading the post regarding the note you received from Stephen Wickland and the hot-skin condition found at an RV park pedestal.

I have been plugging into pedestals to support everything from pop-up trailers to a travel trailer to our current fiver for over 25 years now. I have always had a surge protector plugged in, as well, to protect our investment. The surge protector seemed to do its job and I never really had any problems that I was aware of.

It wasn’t until a few months ago when I read Mike’s article about the additional benefits of using an Electrical Management System (EMS) with Surge protection that I took the step and bought a portable EMS for my fiver. In our first trip (VA to CO and back) we stopped for the night at an RV park outside of Memphis. We set up and initial readings on the EMS showed everything was within tolerances and working fine.

After 15 minutes or so of power being on, the EMS opened its breaker with an “open ground” indication on the readout. I found no additional problems, reset everything and plugged back in. Initial readouts again said everything was fine. Then about five minutes after reset, the EMS opened its breaker again with the “open ground” readout. Probably a ground wire was loose in the pedestal or somewhere in the loop.

I wasn’t going to troubleshoot the RV park’s electrical system so I went up to the office, told them of the issue and was provided a new RV site for our stay. The office personnel did not seem surprised by the problem nor was there any urgency to address the issue from what I could tell. We had no further problems over the next couple of days at our new site.

A camping neighbor there at the park told me that the park often floods since it is on the banks of the Mississippi River and electrical problems are common. I can’t tell if the management did anything to fix the issue but I do know that a motorhome was in the spot a day later. Hopefully the park had a qualified electrician look at and resolve the issue.

So, many thanks for the articles on RV electrical issues. I think the EMS paid for itself during its first trip and I may have never known I had an issue without it. And I wouldn’t have purchased the EMS without the article in your newsletter.

Many thanks. —Charlie Behrle

Dear Charlie,
Thank you very much for your email. Chuck and I feel good every time we hear a story like yours, and we’re happy to help educate RV owners and campgrounds on the best practices of RV electrical safety. 

It’s likely that your intermittent ground was actually something I call a reflected hot-skin/stray voltage. I’ve written about this condition before and you can read more about it here. But your email points to the fact that our mission of creating a Stray Voltage Patrol is badly needed out there. So be assured that Chuck and I are utilizing every possible resource to start our Stray Voltage Patrol and create a nationwide database of campground pedestal conditions. But it will be several weeks before we can even announce the details of how this might work.

In the meantime there are a few things you and the rest of our readers can do to help. In addition to RV owners, we’re really interested in getting campground owners involved. So please take the survey below so we can get an approximation of the scale of this. We’ve had a few dozen comments and emails since our informal announcement last week, which is fantastic. But perhaps there are dozens or hundreds of you who might sign up.

I’m looking for three different levels of Stray Voltage Patrol (SVP) membership: Basic, Intermediate and Advanced. If you want to be a member of the RVelectricity/RVtravel Stray Voltage Patrol, what level do you believe you qualify for? Please answer the following survey based on the descriptions below:

• Basic level – For those of you who plug in with an advanced surge protector with a voltage readout or EMS system, and only feel comfortable testing your own pedestal. You can also add a Non-Contact Voltage Test (NCVT) for your own RV or maybe your neighbor’s RV (with their permission).

• Intermediate level – For those of you also using a digital meter on your own pedestal and maybe the empty pedestals around you (with the campground owner’s permission) and are comfortable taking measurements. Of course, I also recommend a NCVT check since it only takes a few seconds extra and can catch additional wiring problems that a standard meter test can’t detect.

• Advanced level – For those of you who are currently electricians, technicians or engineers. (I know you’re out there because I’ve been getting emails all this week to the effect of, “Put me in, coach.”) I’ll expect even more detailed measurements from you, perhaps including load and impedance tests, and you’ll have the option (with the campground owner’s permission) of testing other pedestals in the campground for correct voltage and wiring.  

• Campground – For campground owners who would like to know how you can help facilitate SVP testing in your campground. This is not an admission that anything is wrong, but that you want to learn more about keeping your customers safe from electrical problems. 

• Individual – Not Interested – For those of you who think this is unnecessary and a waste of time.

• Campground – Not interested – For those campground owners whose pedestals are all fully tested regularly and believe there is no need for further testing.


Remember, NOBODY is sanctioned to measure occupied campground pedestals for proper voltage without the campground and RV owner’s permission. We’re not starting a witch hunt – just trying to determine trends. We’ll also have a way to follow up on any problem pedestals to make sure the problems are corrected.

And yes, we’re working on a rewards system where you’ll receive a $25 prepaid card from RVelectricity/RVtravel for the first pedestal you find with a wiring problem.

After that you’ll accumulate SVP Points and could receive an SVP T-shirt, coffee mug, and big prizes from our sponsors such as an advanced Surge Guard protector, Smart Plug shore power cordset, or maybe even a pedestal outlet for your home base shore power. No promises yet, but the more of you that sign up, the more our potential sponsors will be interested in supporting this program. 

Finally, we also want to know when you plug into a properly wired pedestal with correct voltage. That’s the only way we’re going to be able to determine the percentage of problem pedestals. So you’ll just have to log into the RVelectricity.com/SVP page (not up and running just yet), enter your SVP membership number and password, then enter your data.

We’re going to make this anonymous so your ID number will be the only detail about you displayed. Only I and the inner sanctum at RVtravel.com will know your true identity. Think of yourself as sort of like Charlie’s Angels (or maybe Chuck’s Angels) and you’ll help to save lives and prevent electrical damage to your own RV and others. I know a Stray Voltage Patrol T-shirt isn’t going to make all of us look pretty, but it can’t hurt. 

Feel free to email any questions or comments directly to mike@noshockzone.org with the letters SVP in the Subject line, especially if you’re a campground owner or electrical engineer/technician who wants to get involved.

Let’s play safe out there….


Mike Sokol is an electrical and professional sound expert with 40 years in the industry. Visit NoShockZone.org for more electrical safety tips. His excellent book RV Electrical Safety is available at Amazon.com. For more info on Mike’s qualifications as an electrical expert, click here.



28 Thoughts to “RV Electricity – Hot grounds and the Stray Voltage Patrol”

  1. Roger Spencer

    Could you explain proper grounding for 120 vac & 12 vdc on travel trailers, etc.

    1. RV grounding is something that even electricians and RV technicians get mixed up, so I have to make sure anything I write is 100% accurate. It will take an extended article (at least) to explain this properly, but it’s on my to-do list.

  2. david shipp

    This 220 issue is some thing I have struggled with for a while and even this note by Mike, bothers me. “50-amp/240-volt outlet (which is actually 2 legs of 120-volts at 50-amp each).” Wrong, wrong wrong! I don’t believe you actually think this but instead think you miss spoke. They are two legs at 110 each with 20 to 25 amps each leg. At least they should be since that is the load for most RV’s including mine. That said, when I wire a pedestal, I also wire it so each leg is on the same phase. That means the neutral is carrying the circuit for both legs. That means that a normal cable designed for 220, is likely not suitable for this type connection since 220 circuits do not carry voltage on the neutral, the neutral is often a smaller wire in those cables. Two 110 circuits using only three wires , is carrying both circuits. Some times the cost of two separate cables (getting four conductors and two grounds) is cheaper than buying three wires and one ground. I prefer to use conduit and separate conductors. 25 Amps is 25 Amps and 10 ga copper is more than sufficient. I know of no case where 50 AMP wire is needed in an RV park. Now I want to hear the un-provable argument that out of phase cancels the current in the neutral. I have mentioned this before, but I see no case where 220v is needed in an RV park.

    1. David – Sorry but you’re completely wrong. A NEMA 14-50 receptacle (the 50-amp RV outlet) is indeed two 120-volt legs with 50 amps each, but 180 degrees out of phase. And you’re required to run #6 gauge wire with a double-pole 50-amp circuit breaker, which adds up to 100 amps total current. The neutral current does indeed cancel out to zero amps when both legs are balanced, and the neutral bus size must be the same gauge as the two hot legs. I’ve not only studied this in college, I’ve performed dozens of experiments demonstrating how a neutral current cancellation works.

      It’s all in NFPA-70, the National Electrical Code. Do you have a copy of the latest code to refer to? Let me know and I can send you a link to a free copy to study. But I know I’m 100% right and I didn’t misspeak. Remember, I used to supervise electricians wiring up 3-phase power in a 1,000,000 square foot warehouse, so I eat and breathe this electrical stuff.

  3. Dave

    Mike, I like how you’ve broken down the participation levels. Count me in as someone interested in the Basic level. I want to thank you and Chuck for all your hard work on this subject. We had been weekend campers with our TT for years and never paid too much attention to RV electrical issues. If it worked when we plugged in we were happy. When we bought our new motorhome in May to go full time I decided to listen to all. your advice I’d been reading over the years and invested in a hard wired Progressive EMS and a Hughes Autoformer to protect our new (expensive) baby. WOW, am I glad I did! We’ve been on the road for over 75 days now and I’m shocked at how many parks have problems. Almost HALF of the campgrounds we’ve stayed in have had some type of issue. It doesn’t seem to matter if they are high end or the most basic. Most with problems have been low voltage issues but we had two where our EMS just kept shutting down due to various issues with the lines. No hot skin parks yet. Thanks again for all your hard work and saving me from premature failure of appliances, A/C’s, etc., with your advice.


    In many years of RVing and most of those years checking every pedestal before connecting, I have found two miswired receptacles.

    The most recent was earlier this year at a Florida Escapees park. It had an open neutral. I connected at a nearby empty site and notified the office. A worker was out in a few hours and corrected the problem by installing a new receptacle.

    The other was reversed hot/neutral at a campground in NC about ten years ago. Again notified the office and it was correctly promptly.

    It isn’t a good idea to connect to a power source of unknown quality without testing.

  5. Carissa Miller

    Have you thought about trying to contact campgrounds in groups with educational material on how to test pedestals? For instance KOA corporate, each state poc for the state park systems, other chains? Education (especially about how dangerous it could be if a problem was present) might be a great way to make traction on a large scale.

    1. Mike Sokol

      Chuck and I have already discussed how to get some of the franchised campgrounds to participate. I’m sure we could could get a sponsor to help distribute SVP safety literature at campgrounds around the country to hand out to visitors. But I’ve personally tried KOA and a few others over the last 5 years with zero traction so far. However, once SVP is up and running, YOU (our readers) could be great ambassadors to help get us recognized. Baby steps first.

  6. Bob

    Mike, I haven’t seen anything about those of us that own our own site in a park. We are full-timers and own a lot in a small park where we can always go and rest up and pull maintenance before our next big adventure. What should I be looking for in my own pedestal? Any regular maintenance to pull on it? How is it grounded (I have not seen an attached grounding rod on mine). Any issues with a circuit breaker that isn’t used(i.e. the coach is 50 amp but the 30 amp hasn’t been turned on in five years)?

    1. Let me think that through a bit. I do recommend that all circuit breakers be exercised at least once a year simply by turning them off and on a few times. And a squirt of DeOxit contact cleaner in the outlets once or twice a year should be all the maintenance it needs. But a ground wire is not required since your RV’s shore power cord is supposed to get its “ground” from the incoming power company main service panel, NOT a ground rod at the pedestal. I’ll write up a more formal description of this later.

      1. mike henrich

        This is something on my list to look into. Since a subpanel located in a detached structure, such as a garage or shed, requires a separate ground rod, even though it is fed with 4 wire, isn’t that the same situation as a power pedestal? I could be way off on this, but I plan on looking into it.

        1. Mike Sokol

          I’ll look through the NFPA 70 code concerning ground rods in outbuildings in a few days, but NFPA 1194 (the code concerning how campgrounds are wired) and NFPA 1192 (code specific to RV builds) don’t require ground rods at individual pedestals.

  7. James Collins

    Good catch Mike, was amazed that he thought the 20 & 30’s were 240, I am not an electrician, but have been trained to journeyman standard, and I knew.

  8. Phil Atterbery

    As a retired aircraft mechanic I’ve had a few “negative” experiences with electrical stuff. The phrase “don’t let the smoke out” has been used by some senior electricians. Could this be worked in to the Patrol as an inside joke or slogan?
    Always enjoy your articles. Happy connections.

    1. Mike Sokol

      Yes, the magic smoke that makes all electrical devices work (this is a joke). There was even a Lucas replacement smoke kit for your British cars with wiring that often smoked and stopped working. This is a great read: http://www3.telus.net/bc_triumph_registry/smoke.htm

  9. David Earl Ozanne

    I ran into a pedestal problem a couple of years ago. I found it had no neutral. When I informed the owner, the electrician came out to check it. He told me that the neutral and the ground were one and the same. After I told him that in RV’s it was not true, he rewired the pedestal. He had been an electrician for about 40 years, but only worked on housing electricity.

    1. Hmmmmm….. This electrician is misinformed. The neutral and ground in a house have not been the same wire since the late 1960’s and 70’s when code began requiring separated neutral bus bars in all service panels. I remember it because I was there. Yes, my first home wiring projects started around 1966 when I was 12 years old and apprenticing under a master electrician who also taught residential wiring at the local Vo-Tech center. He has a few interesting stories about me that he told his classes decades later. Suffice it to say that I didn’t die, but there were some serous arc-flash incidents while I was learning.

      1. Mark Robbins

        Mike, I’m definitely interested in being involved. I am only qualified to do the basic. I do use a surge protector and have a NCVT that I have been using thanks to your advise over a year ago. Thanks for educating us!!!

      2. Sherry Dawson

        Mike, one of my concerns is that I wouldn’t know how to counter an argument from an electrician if I find a problem. I have read and stored everything you’ve written on RVTravel in the last 3 years, and understand most of it quite well. I will become part of the Stray Voltage Patrol when I go full-time. Could you give some thought to providing us a list of comebacks to incorrect responses we get from electricians when we report a problem? As it would be a list that grows with time and reports from the Patrol, it could be on the Patrol website and updated as we report such encounters. Thanks to you and Chuck for starting this. I think it will save lives and Rvs!

        1. Sherry,
          Yes, it’s difficult to convince an electrician that an RV owner just MIGHT know something they themselves don’t know. But there’s a lot of documentation that can be used to convince them. For instance, the TT-30 outlet which is the shore power connection for all 30-amp RV shore power is plainly marked as 125-volts max, and yet I still get emails every week about some electrician who ignored it and wired up the 30-amp/120-volt RV outlet like it was a 30-amp/240-volt dryer outlet. And that can burn up all the electronics in your RV within minutes. So better to say stop, then get a second opinion. However, it’s a little harder in campgrounds since many of these maintenance guys aren’t real electricians at all, just work campers replacing campsite pedestals, etc… I’ll do some thinking on this, and you’re correct that as our SVP database grows it will provide a useful backup for when the campground maintenance guy tells you that there’s nothing wrong with an open ground or whatever. This will take a while, so stay safe and keep reading. And if something seems crazy and the campground or maintenance guy won’t fix it, then walk away. Nothing is worth as much as your life, which is why I tell everyone to “be careful out there.”

  10. mike henrich

    It may also be a good idea if there would be a flyer to give to campground management on the safety and importance of have the pedestals checked. Maybe each member could email the campground ahead of time to let them know a member of the SVP will be staying there. Funny thing about this whole idea, I’ve been considering starting my own business, and 1 of the things I was thinking of doing is contacting campgrounds in the area and trying to “sell” a safety check. I am very interested to be a part of this. Thanks.

    1. Mike,
      Excellent. Yes, I’m working on a flyer to hand to the campground management explaining what we’re (you’re) doing and why we’re doing it. For now this is a grassroots effort, but the end game is to help set up hundreds of safety check businesses around the country affiliated with the SVP that would charge each campground in their area for a yearly inspection of all pedestals, and place a dated tag with the inspectors’ initials. That’s why I’m looking for RV Electricity readers who are already Electricians, Electrical Technicians and Engineers.

      1. mike henrich

        Definitely count me in. I’ve been an electrician for 30+ years, in all aspects of electric. I love the idea of the meter to check all receptacles at the pedestal.

  11. ,Richard Davidson

    I am a qualified electrician of 30+ years in the industry and am also on the BOD of our winter campground/condo association. We are 2 blocks off the ocean in Florida so we have our share of electrical problems from sea, salt and wind. Our CG is old and our infrastructure is old too and unfortunately our wiring is underground aluminum which doesn’t fair well in this environment. We have had episodes of lost grounds and neutrals etc. and I have been following your articles on hot skins and stray voltages. I agree completely that parks need to be responsible in checking their systems but again things happen and not everything can be caught before something breaks or shorts. So at our park I am trying to implement a program whereby each pedestal is checked before a renter plugs in. OUR problem is our town will not approve pedestals that have 120V plugs in them. Only 220V 30 & 50 amp. (cannot get an answer as to why) As every meter I can find must plug into a 120v outlet I am stumped as to how to do this check. Unless I use a dog bone spliced into a 120v female plug end I can see no other way to do the necessary checks without using a multi meter. This would require someone who knows how to actually do the checks rather than just someone to plug in and check the lights and our maintenance staff is not exactly qualified to do this. (we are a small park) Do you know of any GFI/polarity checkers which plug into 220v 30/50amp plug like we have at the campgrounds? Any suggestions would be much appreciated.

    1. Richard, we need to talk. There are NO 30-amp/240 volts outlets for RV pedestals in the United State. There’s a 20-amp/120-volt, a 30-amp/120-volt and a 50-amp/240-volt outlet (which is actually 2 legs of 120-volts at 50-amp each). But yes, I’m working out the proper dogbone adapters to use a standard Suretest analyzer to not only gather voltage readings, but ground impedance and voltage drop under load as well. You could be one of our field testers of this protocol if you’re up for it. Shoot an email to mike@noshockzone.org with your phone number and let’s set up a time to discuss.

      1. Richard Davidson

        Sent you an email.

    2. TIM BARD

      Scary to think that a self proclaimed qualified electrician believes RVs use 220v 30a receptacles. They do not.

      1. Yes, over the last 10 years I’ve received at least a hundred emails talking about residential electricians mis-wiring a 30-amp TT-30 outlet with 240 volts instead of 120 volts. It can do thousands of dollars in damage to the RV’s electrical system in a just a few seconds. NEVER trust a residential electrician to wire anything for your RV without double-checking them before plugging in. And an Intelligent/EMS surge protector is your best friend.

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