Tuesday, June 6, 2023


RV Electricity – No~Shock~Zone by Mike Sokol – Issue 9

Issue 9 • July 29, 2018
Brought to you as a public service by RVtravel.com. Support comes from our sponsors, advertisers and the contributions of readers, who believe that an educated RVer is a safe, happy RVer. 

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Welcome …

By Mike Sokol

stray voltage patrolHere’s the latest update on the Stray Voltage Patrol (SVP). We’ve already received around 4 dozen sign-ups, which is fantastic. If you haven’t signed up but want to, go HERE to sign up for the SVP program. If the link or the sign-up form doesn’t work, just email me and I’ll put you on the mailing list for project updates. My email address is mike (at) noshockzone.org .

If you’re new to this newsletter, RVtravel.com editor Chuck Woodbury and I have begun organizing a nationwide program that will empower RV owners across the country to identify campgrounds with power problems. The first round of the SVP will be to find hot-skin/stray-voltage conditions that can become a shock and electrocution hazard under the right conditions. The Stray Voltage Patrol is not up and running just yet, but we’re already getting great questions and comments from the field, which hastens our steps.

Here’s just one example I received recently:

Mike, I really appreciate the information on electrical safety. On your recommendation, I purchased a smart surge protector as well as a couple of NCVTs. (Gotta have one for around the stationary house, as well!) Given the fact that the surge protector can detect a number of problems with the power source, what would be a good protocol for using them in combination? Would it be wise to start by checking the power pedestal with the NCVT first? Thanks for your advice. —Chuck Barke

Dear Chuck B.,
Here’s the power testing sequence I can recommend for the general public. Before you pull into your camping spot take your NCVT (Non Contact Voltage Tester) for a quick, hands-off check of the campground pedestal for hot-skin/stray-voltage. Turn on your NCVT and make sure the batteries are OK by checking the indicator light and listen for a beep. Don’t touch the pedestal box with your hands yet until you confirm it’s not electrically hot. No need to scrape or rub the tip of NCVT on the metal box, and the circuit breakers don’t have to be on at this point. 

IF THE PEDESTAL BOX has more than 30 volts on it, then you should get an NCVT alert if you make contact or even get close to the metal. If that happens, DO NOT touch the pedestal box with your hand or pull your RV into the campsite and hope that it will be fixed before you’re all set up. Get the campground manager and show them what you’ve found, then ask for another campsite. Also, it’s time to report this condition to the SVP data site (not up and running just yet).

Next, if you have a portable Intelligent/EMS Surge Protector, take it over to the pedestal and plug it in, then flip the circuit breakers on. If you don’t have an Intelligent/EMS, then it’s time to get your Digital Multimeter (DMM) and test the outlet for proper voltage and polarity. If it checks out as OK, then you can turn off the pedestal circuit breakers and proceed to drive your RV onto the pad to get set up. If your test shows really low voltage, high voltage, reversed polarity, or an open ground, then don’t pull into the campsite. Get the campground manager and show them the problem. 

Once your RV is in position and you’ve confirmed the pedestal circuit breakers are off, go ahead and plug your shore power cordset into the outlet, then flip the circuit breakers on. Pull out your NCVT again and touch it to the bumper, hitch or wheels of your RV to confirm that the chassis/skin of your RV doesn’t have a hot-skin/stray-voltage due to a break of the ground wire in your own shore power cord or adapters. If it beeps, then there’s something wrong in your shore power cordset or adapter. Disconnect your RV from shore power until you can determine the cause of the hot-skin/stray-voltage. 

This test procedure, which will add only a few minutes to your load-in time, should virtually guarantee a safe power hookup under 99.9% of all circumstances I can imagine. And if anything changes while you’re there, your Intelligent EMS/Surge Protector should warn you and disconnect your RV from the incoming power.

Yes, I need to make a video of this procedure as well. It’s on my honey-do list. 

Making campgrounds safer, one pedestal at a time…


P.S. And just a quick note that this newsletter is made possible by the voluntary pledges of the readers of RVtravel.com. We could not bring this to you without their support. If you deem what we provide to you here and at RVtravel.com to be of special value and would like to be a part of our effort, please consider becoming a member-supporter by pledging a voluntary subscription. More information is here. We will include you in special emails, articles and videos exclusively for our supporters.

And mark your calendars!
I will present RV electricity seminars at the Forest River FROG Rally, August 12 to 18, at the Elkhart County 4-H Fairgrounds in Goshen, Indiana. For more information visit frogrally.com. Later, September 12 to 16, I’ll be a featured seminar speaker each morning at America’s largest RV show in Hershey, Pennsylvania. Hope to see you at one of these fine events.

Save your propane!
Easily convert to electric heat!

SAVE $$$! Until now, the standard for heating recreation vehicles of all types has been to use bottled propane (LPG). With the CheapHeat™ system there’s a better option. Now you have a choice to change the central heating system between gas and electric with the flip of a switch. When you choose to run on electric heat rather than gas, your coach will be heated by the electricity provided by the RV park. Learn more.

Pedestal Power

Pedestal power has changed in recent years
Today’s RVs have much greater power requirements than those of even 10 years ago. You have lots of appliances, so that single 20-amp outlet can’t provide enough current. This is when you need to step up to a 30-amp or 50-amp outlet at the campsite. Let’s see how they’re wired.

Read More… 

Email me at mike (at) noshockzone.org with your questions.

Your RV is generally your second largest physical asset. Protect it!
Home Electrical Box: 50-30-20 amp surface mount box • Breakers & receptacles included • Outdoor rated • UL listed • Pedestals also available. 30 & 50 Amp Surge Protector & Reverse Polarity: Continuously monitors & displays voltage & amp draw (RMS). Tests for & indicates: Reverse polarity • Exclusive open neutral inside the RV • Miswired pedestal • High neutral currents • Surge protector. Contact us at 800-500-2320 or RVpowerOutlet.com.

Industry Updates

Winnebago builds electric campers — to tow your electric car?
Really, are we there yet? Can you breeze past those stinky truck stops with your RV coach and not burn a drop of diesel? Not just yet.

I have some insider knowledge in this area (the Volvo/Mack Truck engine and transmission plant is right down the road from me), plus I know enough about the latest battery technology to predict a totally electric-powered Class A, B or C (maybe E?) RV for general use ain’t happening anytime soon.

Did you know that in 1899 and 1900, electric vehicles outsold gasoline-powered ones? And companies like GMC built and sold a few electric local delivery vehicles in the early 1910s. We’ve been trying to do this for 100 years already, so don’t expect an overnight breakthrough. 

However, lots of RVs are bought and retrofitted for applications other than driving your family around the country. For instance, bloodmobiles, bookmobiles, police command centers and school buses that have limited, local routes are the first applications up for conversion to electric operation – especially when you consider all the idle time these diesel engines have to do. So look for your local post office delivery vehicle to go electric powered first, but don’t wait for your Electric Class A anytime soon.

Yes, it will happen eventually, but only after the heavy trucking industry gets in the game and the battery technology takes at least a 10 times leap in power density. Stay tuned and I’ll update you as I learn more.  

Read the Green Car Report HERE.

— Mike

Survey Question

Have you ever encountered a campsite pedestal outlet without a way to disconnect power before plugging in?

To be in compliance with the National Electrical Code, all pedestal outlets are required to have a power disconnect switch within 3 feet of the box. This can be in the form of a circuit breaker inside the pedestal box, or a disconnect handle on the side of the box. That’s so you can easily turn off the power before plugging in or disconnecting your shore power cordset. I’ve had reports of some pedestal outlets having neither, forcing you to plug in “hot.” And at least one reader told me of a campground that put electrical tape over the circuit breakers in the ON position so you couldn’t turn them off and “wear them out.” Please answer the survey question below to help us identify how often this sort of thing occurs. 

New & interesting finds at Amazon.com
See what really cool stuff Amazon is featuring today. It’s a whole lot of fun just browsing through all these great items. The selection changes every day, so check back often. You never know what you will find, which is part of the fun of visiting here. Check it out.

Portable USB Turntable shown above.

Click image to enlarge.

Last month’s survey results:
What kind of generator do you use?
It appears that a whopping 25% of you use a portable, enclosed inverter generator, which is good for the noise environment. And nearly 60% of you have built-in generators which are generally very quiet. But 5% of those who took the poll are using open-frame contractor generators that make a lot of noise. I’m sure it’s a cost thing, so I’m still working on my survey of “affordable” enclosed inverter generators. Watch for it here…

Tools and Other Devices

Big cable cutters
I often have to cut really heavy gauge wire for my power distribution cables, and recently had one of my buddies ask me to help run and hook up some new battery cables for his RV. Lucky for him I was able to pull out my pair of Southwire CCP9 High-Leverage Cable Cutters. These will slice through copper wire up to 2/0 gauge with very little effort, and leave a nice clean-cut end. Available in your local Lowe’s store or on Amazon.

Last Month’s RVtravel.com Posts

What makes a generator “RV Ready”?
ABCs of generator noise.
Focus on “Stray Voltage” – What is it and why should you care?
Hot grounds and the Stray Voltage Patrol.
Using a Non-Contact Voltage Tester (with important video).

Stock up on these common RV LED lights!
If you aren’t lighting your RV’s interior with LED lights, you’re wasting energy and even money. And if you already do have LEDs, they’ll burn out at some point and will need to be replaced. This 24-pack of perhaps the most common lights will come in handy, and for about $1 per light. It’s hard to imagine you’ll find a better price than that. Learn more or order.

Q&A’s from Forums

I spend a lot of time on dozens of RV forums and blogs answering questions about electricity. Here’s one from my own No~Shock~Zone blog:

From the No~Shock~Zone

Q: Mike, is this Tesla charger welder-plug adapter really safe to use for an RV with a 50-amp shore power cord? Article info on some of those adapters says it can be used for RV service!! Thanks.  —Kenny

A: Kenny, just because you can plug something together with adapters, doesn’t mean it’s a good idea. The Tesla car needs 240 volts without a neutral for charging, so if you hook this adapter from a welding plug to a Tesla via its 14-50 plug adapter, that will be OK.

However, your RV is not a 240-volt device, but instead requires a pair of 120-volt legs at 50 amps each with a neutral wire for the unbalanced current. So if you plug this adapter into a NEMA 6-50 welding outlet (on the left), and your RV shore power cord into the 50-amp “RV” outlet (technically a NEMA 14-50R receptacle), the EGC ground wire in the welding outlet will be used to carry the neutral bus current coming from the RV, and it’s not designed to do that. Then if the neutral bus opens up for any reason, the 120-volt appliances in the RV could receive up to 200 volts AC or so, destroying them in seconds. This might work for your RV on some occasions under very limited power draw, but it’s a dangerous code violation for a lot of other good reasons that I can think of.

DON’T DO IT!!!  Mike

Email me at mike (at) noshockzone.org with your questions.

The best book on RV electricity, hands down!
RV Travel contributor Mike Sokol is America’s leading expert on RV electricity. Mike has taken his 40+ years of experience to write this book about RV electricity that nearly anyone can understand. Covers the basics of Voltage, Amperage, Wattage and Grounding, with additional chapters on RV Hot-Skin testing, GFCI operation, portable generator hookups and troubleshooting RV electrical systems. This should be essential reading for all RVers. Learn more or order 

Videos by Mike about
RV Electricity

• This is my latest video on how to use a Non-Contact Voltage Tester to check for an RV Hot-Skin/Stray-Voltage. This could save your life so please watch it HERE

Tesla vs. Edison: The Life-Long Feud that Electrified the World
Nikola Tesla is largely overlooked among the great scientists of our modern era. While Thomas Edison gets the glory for discovering the light bulb, it was his one-time assistant and life-long arch nemesis, Tesla, who made the breakthrough in alternating current electricity. Today all homes and electrical appliances run on Tesla’s AC current. This book is fascinating!

Road Signs

Which came first? The Chicken Tax, the Sprinter RV or the Egg? 

A lesson in tariffs and international trade
By Mike Sokol
This is not a political article, and I’m not taking sides. However, I believe that “Those who cannot learn from history are doomed to repeat it.” This is the story of how a cheap chicken in the 1960s changed international trade and how your Sprinter van is currently built. And it’s also a warning that every tariff has repercussions, some good, some bad, and some reaching 50 years into the future in unpredictable ways.

Read more…


Editor: Mike Sokol. RVtravel.com publisher: Chuck Woodbury. Managing editor: Diane McGovern.

Everything in this newsletter is true to the best of our knowledge. But we may occasionally get something wrong.  So always double check with your own technician, electrician or other professional first before undertaking projects that could involve danger if not done properly. Tips and/or comments in this newsletter are those of the authors and may not reflect the views of RVtravel.com..

Mail us at 9792 Edmonds Way, #265, Edmonds, WA 98020.

This website utilizes some advertising services. Sometimes we are paid if you click one of those links and purchase a product or service. Regardless of this potential revenue, unless stated otherwise, we only recommend products or services we believe provide value to our readers. Amazon and the Amazon logo are trademarks of Amazon.com, Inc. RVtravel.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.

RVtravel.com includes links to other websites. We cannot control the content and/or privacy policies of those sites. Please be aware when you leave this newsletter or any other section of RVtravel.com to read the privacy statements of any of those websites that collect personally identifiable information. Our own privacy policy applies only to RVtravel.com and its affiliated blogs and websites.

This newsletter is copyright 2018 by RVtravel.com.


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Michael Butts
4 years ago

About a month ago, we drove from Michigan across Canada to the Atlantic. We found at least two small campgrounds at conservation areas that the 30 A receptacle was mounted on a 4×4 post. No cover, no breaker, no 20 A outlet as we’re accustomed to in the USA.

4 years ago

I have seen RV receptacles with no cutoff available to the user in a number of places – my garage is one, breakers in the panel in the garage in sight but 20-30 feet away. Also, Montgomery County Fairgrounds in Gaithersburg Maryland has panels between sites built like bulletin boards with four 30 amp plugs on each, locked disconnect boxes, and breakers in locked panel on nearby building (in sight if no RVs present.) I also found another older panel with lots of breaker boxes, one 50 amp receptable, and 30 amp and 20 amps with reversed polarity (which I discovered when my “cheater” box tripped the breakers.) Their newest boxes are 50-30-20 pedestals with breakers in the pedestal.

4 years ago

The procedure at the top of this article is great. But for newbies (or those of us who are just forgetful), a checklist we could print and keep with our surge protector and non contact voltage detector would be an awesome way to always have this info handy.

Mike Sokol
4 years ago
Reply to  Mike Sokol

I just published a separate article on my pedestal power test procedure that includes a printable pdf checklist.

Chuck Barker
4 years ago

Thanks, Mike, that perfectly answers my query!

4 years ago

MIKE, how can you say you can plug that EMA 6-50 plug into you 50 amp RV plug. Don’t think you could even do it with a hammer. For sure I must have misunderstood something!

4 years ago

Seems most RV sites in Alaska & Canada have only 30 amps but most don’t have a disconnect, very scary. happily I have a smart EMS hard wired & felt pretty secure, I never had an issue, just saying!

Tom Barone
4 years ago

Mike, entered a campground in Penhook VA, on Smith Mountain Lake, I cannot remember the campground name in October 2014. Only receptacle on the site was in a broken 50 amp receptacle in a broken 4×4 plastic box, no 30 or 20 amp receptacles. The conduit was also broken with exposed conductors and box laying in tall wet grass as it was raining, apparently when the grass is mowed they just go around it, no 4×4 post or stick to mark the location. Hot terminals exposed and no breaker within site, attendant did not know where the breaker panel was. I asked the attendant for another site and upon inspection it’s electrical service was in the same condition. Left the campground and found another.

4 years ago

I have been to a number of rallies such as motorcycle clubs and even Good Sam where temporary wiring did not provide a breaker that was readily accessible.

I have also been to a few privately owned campgrounds that did not have a breaker at the site pedestal.

Mike Sokol
4 years ago
Reply to  TIM BARD

Interestingly, it’s up to the AHJ (short for Authority Having Jurisdiction) or local electrical inspector as to what is required for a particular state, county, city and campground. So it’s within their rights as a local inspector to ignore parts of the National Electrical Code. However, IIRC every manufacturers’ literature I’ve read doesn’t recommend plugging in while the pedestal is “hot”. The workaround is for you to shut off the RV’s main internal circuit breaker before plugging or unplugging from shore power.

SFC Dennis R Strope, USA, RET
4 years ago

Thank you for the informative info you and Chuck provide, makes life simpler and safer. Don’t know where to pose questions to you so here goes. I once had to use generators to power RV, in boondock mode and used surge protector. It caused surge protector to malfunction and had to buy new one, was told that surge protector was not needed with generators/inverters. What can you tell me(us) about that. Currently have champion inverters with parallel connector. (FOR 50 AMPS) thankyou.

4 years ago

Partly offtrack from the survey, but the 3 foot NEC guideline was interesting. The cut offs for my hot tub and home RV pedestal are both located more than 3 ft from the endpoint (still close enough to be used in emergency). The installers’ rationale was that if something were wrong you don’t want to be standing in the tub or too close to a shorting/melting RV plug in order to shut it off. Concise campground pedestals make sense, but what do you think of home pedestals with a subpanel cutoff 5-7 feet from the actual plug?

Mike Sokol
4 years ago
Reply to  Wolfe

If your local inspector will pass it, then I think that should be fine. I don’t think they’re running around with a tape measure, but there really should be a cutoff in the vicinity.

John Koenig
4 years ago

Sunday July 29th 2018 1240 hours (MST). The above link is STILL non-functional (404 eror received). I AM interested. P;ease advise when/where/how I can sign up. Thank you!

RV Staff
4 years ago
Reply to  John Koenig

Sorry, John. We’re working on it. Thank you for your patience in the meantime. —Diane at RVtravel.com

Mike Sokol
4 years ago
Reply to  John Koenig

John, please try it now and let us know. We really have been working on this all day and the word is that it’s now operational. But please let us know.

Ben C
4 years ago

Just tried the sign up link, got page not available.

John T
4 years ago

I stayed at Black Canyon RV Park in Cimarron, Colorado, last month, and there were no breakers on the pedestals – just fuses. Very unsatisfactory.

4 years ago

Hi Mike. I purchased a stray voltage detector. I was testing it out in my house before I put into my RV when I got it near a table fan with a metal cage the tester indicated the cage was hot. This is an old fan without the 3rd ground wire. Is this fan safe to use?

4 years ago

Mike “Your RV is not a 240 volt device” is true, but if your RV has the CheapHeat hybrid heating system may very well have a 240 volt device in the RV. Your Hybrid Electric heating system.
Because as you said an RV 50 amp system is a true 240 volt system at 50 amps with two legs at 180 degrees out of phase for a useable total of 100 amps at 120 volts. You still have the ability to use a device that uses 240 volts because with a neutral you have both options 120 and 240 volts.

Armand MInnie
4 years ago

I bought a Sperry VD6505 non-contact voltage sensor and don’t really understand how to use it. It has a sensitivity adjustment with no indication of the actual setting. If I adjust it for high sensitivity it shows voltage when I get anywhere near (2 feet or so) some voltage. I don’t know how I would be able to use it on a typical pedestal. Is it usable for this purpose?

4 years ago
Reply to  Armand MInnie

Mike hit it on the head with needing consistency – you need to *know* what the instrument is telling you. If you can tell your NCVT 1) is on and working and 2) the difference between hot and not, I think it should be usable. I haven’t seen a NCVT with infinate/unknown adjustment, so most likely you have off/low/high and should just be using the lower range.

I have about 6 NCVTs and two go up to the crazy sensitivity level you mention. One has O/L/H (where high detects current anywhere near – good only for a last check for blind demolition), and the other has no adjustment but has a discrete segmented bargraph/tone from quiet tick to scream. Try scanning your lampshade vs the lampcord – the tick vs scream difference should be obvious and unmistakable.

4 years ago
Reply to  Wolfe

Geez… I stand corrected!!! Your Sperry VD6505 does indeed have a dial. You could tune and ducttape it, but I’m throwing in with Mike that a $3 tester is safer for this purpose.

David Chamberlain
4 years ago

Hi, please add my name to the list as the link didn’t work for me either.

Mike Sokol
4 years ago

David, please try it now and let us know. We really have been working on this all day and the word is that it’s now operational. But please let us know.

Rodney Helfrich
4 years ago

Only once, I opened my main breaker before plugging in.
It was a very old camp ground.

4 years ago

I have encountered a campground with a “hot” 50 amp plug in but the circuit breaker was in a remote location about 50 to 100 feet away. I could not even figure out which circuit breaker controlled the plug box. In another instance, the park put in new electric panels but left the old ones in place. Very confusing.

Karin S.
4 years ago

I clicked on your link to put my name on the Stray Voltage Patrol list but it does not appear to work. Mike mentioned approximately 4 dozen folks have signed up, but the actual “patroling” has not started yet. I would like to add my name to the list, so when the team is activated I would be ready to participate.

Mike Sokol
4 years ago
Reply to  Karin S.

Karin, Yeah we’re having database problems this morning. I’ll manually enter all of you so expect a followup email later this week.

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