Saturday, May 27, 2023


RV Electricity – No~Shock~Zone by Mike Sokol – Issue 18

April 28, 2019

Brought to you as a public service by Support comes from our sponsors, advertisers and the contributions of readers, who believe that an educated RVer is a safe, happy RVer.

Subscribe to one of our many online newsletters (including this one) about RVing.

Read back issues of this newsletter and many other articles by Mike Sokol on Warning: There is a lot to learn here.

Welcome …

By Mike Sokol

It’s spring (finally) and time to get ready for a fun season of traveling and camping. I’m super excited to be presenting a number of RV Electricity seminars this summer and fall, which began with the RVillage Rally 2.0 last month in Florida. I’ll be in Goshen for the Ramblin’ Diesel Pushers Group maintenance clinics on May 4th, going over transfer switch and cord reel maintenance. Then on to Alumapalooza (yes, the Airstream Factory) at the end of May

The big news is my June 8th troubleshooting clinics for RV owners in lovely Funkstown, MD (literally a few hundred yards south of Hagerstown). If you plan to attend, you can now reserve your seat. The morning seminar will cover the basics of RV electricity ($15 for our members and $25 for others). The afternoon session ($100 for members, $125 for non-members), will be longer and cover more advanced troubleshooting topics. members should have received a discount code in their member edition of yesterday’s newsletter so be sure to use that code. Seating is limited, so please make your reservation ASAP. Click here to learn more and/or register.

facebook logoPlease join me via a live video chat tonight (Sunday) at 9 p.m. Eastern time (6 p.m. Pacific). Click here to watch (you will need to be a member of the Facebook RV Electricity group to join in the live chat).

Below you’ll find Part 2 of my article on RV Hot-Skin Voltages. This is starting to get into the complex theory of troubleshooting them, so if you’re a beginner this may not be for you. However, be sure to show it to whoever works on your RV’s electrical system.

I’ve also begun a knowledge “difficulty rating system,” just like you would find on hiking trails. So if you see a Green Circle at the top of a page, it’s an easy-to-understand article. A Blue Square is Intermediate Technical Level, a Black Diamond is Advanced Technical Level, and a Double Black Diamond is Expert Technical Level, so proceed at your own risk.

My plan is to use the Easy Tech Level topics in my JAM (Just Ask Mike) Sessions, reserve the Intermediate Tech Level for the weekly RV Travel Newsletter, and publish the Advanced Tech Level articles in my monthly RV Electricity Newsletter (what you’re reading right now). Don’t worry if you don’t understand the Advanced article right now, but keep studying the Easy and Intermediate Tech Level articles and you’ll get there.

Also, I’m having a kitten (actually, a bunch of kittens). Read more about it in my Road Signs column at the bottom of this page.

Let’s play safe out there… 

P.S. Be sure to join my new (and very popular, I might add), RV Electricity Group on Facebook, moderated by yours truly and hosted by Lots of great questions from our members and important electrical information for your RVing safety.

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

Advanced Electrical Concepts

What is an RV Hot-Skin Voltage? – Part 2

As promised, this is Part 2 of an article series on Hot-Skin voltage. If you haven’t done so already, please read about the basics of Hot-Skin voltage in Part 1 HERE, so we’re all at the same starting point. You’ll also need to read my RV 101 article in magazine format which was linked to last week. Read it HERE. Once you read all that, you’re ready to proceed with advanced troubleshooting concepts of RV hot-skin/contact-voltage.

Ready… Set… Go!

This article is rated as Advanced Tech Level since it involves complex troubleshooting concepts with potentially dangerous voltages. Do NOT attempt to perform these tests on your RV unless you’re properly qualified to work around live voltages. 

Read more…

Today’s Deals at
More than 1,000 great products at big discounts. Click.

Industry Updates

Progressive Industries is alive and well…

I had at least a half-dozen emails and text messages last week from readers saying they couldn’t get ahold of Progressive Industries on the phone, and their website appeared to be down. Indeed, I couldn’t load their website for a few hours. Of course, everyone is worried about companies going out of business, which is understandable.

So I just talked to their customer support department this morning, and they are alive and well. The support person said their IT department had technical problems last week, which affected their web page and probably took their phone system down as well. But all is well, so not to worry. Here’s a LINK to their main webpage in case you need it.

Survey Question

Do you have a preventive maintenance list you check prior to your first RV trip of the season?

Curious minds want to know. Please take the 30-second survey.

Last month’s survey results:

(click image to enlarge)

How many of you take a boat along on your camping trips or swim around boat docks that have electrical power?

So it appears that 15% of you (1 in 7) do have a boat or use boat docks for swimming while you’re vacationing with your RV. I’m finishing up Part 2 of my article on ESD (Electric Shock Drowning), which I’ll publish in the newsletter next week. In the meantime, be aware that even small electric shocks can be life threatening around water, and it’s an invisible killer. Here’s a story from just last week about a teenager being electrocuted in a small drainage canal while trying to rescue a dog. The metal walking bridge over the canal became energized and when he touched it to get out of the water he was electrocuted. Read the full story HERE.

Tools and Other Devices

Don’t trust a tire shop with your lug nuts!

My sister just called to tell me that her friend with a nice Nissan truck is sitting in a ditch along I-5 in California with their vehicle suspension shredded and the lost wheel mangled beyond use. Yes, they had just left a quickie tire shop and got on the Interstate. You guessed it, the kid who mounted their tires never bothered to tighten the lug nuts on at least one of their wheels. While nobody was hurt, there’s thousands of dollars in damage, a lost day (at least), and it could easily have turned into a real disaster at 70 mph.

All three of my adult kids and I carry torque wrenches in our vehicles, and we run around for a quick torque check after anyone has touched a wheel on our cars or trucks. And I’ll do a monthly check of lug nut torque if I’m doing any serious traveling. You’ll want a nice 1/2″ drive torque wrench with the appropriate drive socket for your wheels. And check with the wheel manufacturer for proper torque specs, especially if you have aftermarket alloy wheels.

Any big box store such as Lowe’s or Home Depot will have torque wrenches for sale, and many include a nice case for stashing it behind the seat (or wherever). Just don’t forget to use it, especially right after anyone has touched your wheels, and 100 miles after. It’s surprising how much they’ll loosen up after a little drive. Here’s a good choice from Teckton for wheel lugs up to 250 ft/lbs of torque.

Yes, if you have a REALLY BIG coach this isn’t the torque wrench for you. But you’ll likely have to get a truck mechanic just to loosen your wheel lugs at all and hoist a big tire into position. But since I worked in a truck tire shop as a teenager mounting semi-truck wheels, I would probably get an impact wrench and 10-ton bottle jack if I had a coach. And NO, I will NOT change the tire on your diesel pusher.

Last Month’s Posts

What is hot-skin voltage? – Part 1.
Can an RV be plugged into a Tesla charging station?
Weekly update, and 50-amp pedestal wiring.

Last Month’s JAM (Just Ask Mike) Session posts:
These articles are rated Easy to understand for beginners.

Disconnect power during a storm?
Surge Protectors for 30- or 50-amp power?
Should I turn off circuit breakers?

cord-753Don’t come up short!
Sometimes your 50-amp power cord is not quite long enough! That’s when this 15-foot extension cord will come in very handy. Sure, you can use a wimpy orange extension cord with an adapter — and risk burning up the cord, ruining appliances, or maybe even burn up your rig! With this cord along you’ll be all set. Learn more or order.

Q&A’s from Forums

I spend a lot of time on dozens of other RV forums answering questions about electricity. Here’s one of them:

From an Airstream owner

Q: I’ve read your online posts in the course of attempting to answer this question: Should I drive a ground rod for my up-on-blocks 1967 Airstream?

Code calls for a separate ground to any subpanel in a separate building, which this effectively is, RV convention notwithstanding. The Airstream subpanel has ground separation from neutral but the subpanel ground is bonded to the frame and skin. I have a surge breaker in the main panel in the house, and being in a high-lightning-strike zone, I want to give the Airstream (and connected devices inside) the best chance possible. Lightning would follow ground to inside devices and back to the main panel, as well as partially following to earth proximate to the Airstream.

I’m leaning towards the local earth ground rod as the new shortest and lowest impedance path, maybe even one on each end of the trailer, as the trailer is currently dangling out on the end of a grounding invitation (like a kite, or so it seems to me). But then also thinking to add a separated lightning diversion (braided cable plus spikes) over the top as the earth-grounded trailer would then be an even more likely strike attractor relative to other objects in the neighborhood… I think. What do you think? —Christopher

A: Dear Christopher,
While a grounding rod isn’t needed for any RV pedestal or RV, it can’t hurt and is allowed by code as part of the distributed grounding system. However, a grounding rod can’t be a substitute for a low impedance EGC (Equipment Grounding Conductor) path back to the power company’s incoming service panel.

As many of you have read in my many lightning columns, the primary reason for a ground rod is to drain away currents from nearby lightning strikes, and even direct hits. Since you’re talking about a permanently installed Airstream on blocks (not wheels) then it should be treated like a mobile home, electrically speaking. So I believe it’s a good idea to add a ground rod (two is probably the best idea if your soil conditions aren’t perfect), to your Airstream’s incoming electrical system using all the installation methods and materials required by your local electrical code. Please send pictures.


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

Mike’s first Live Stream for his RV Electricity Group on Facebook

Camco Store at
There isn’t much you need for your RV that Camco doesn’t have. If you think we’re kidding, then click through to the Camco store on Amazon where you’ll find some of their best-selling products — all for your RV or for you to make your RVing better. Click here and you’ll feel like a kid in a candy store.

Road Signs

By Mike Sokol

What I’ve learned from kittens

It’s spring and time for many animals to give birth to their young. I just happen to have a bunch of brand-new kittens to play with.

Read more…


Editor: Mike Sokol. 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

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, Inc. 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 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 to read the privacy statements of any of those websites that collect personally identifiable information. Our own privacy policy applies only to and its affiliated blogs and websites.

This newsletter is copyright 2019 by


0 0 votes
Article Rating
Subscribe to comments
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments
robert f viens
3 years ago

I have an electrical/possible generator issue that may be connected. We have a 2012 Monaco Lapalma SFS30 gas engine 30 amp service. The gen is a 4.0KW gas Onan. We were boondocking on running the gen and I turned the electric heat and after a couple of minutes the gen would shut off. The gen was throwing a code 12. We had just driven through Pa and NY interstate on our way to the Tapanzee and the roads were the worst I just thought maybe a ground wire had come loose. I turned the electric heat on again and noticed the gas heat was also turning on at the same time. The RV came with the Coleman 8530-348 thermostat. The gas heat and electric heat are separate on the thermostat. So now I am thinking that there is an issue with the thermostat. My question,is it possible that with both heat sources on that it is causing the over voltage code 12 on the gen. Thank you for all you do. It is much appreciated.

4 years ago

Hi I got a question I had a 30 amp camper then I just traded in brand new 50 amp camper so I have a 30 amp power surge so will it work if I use my 50 amp camper if I purchase the plug that plugs in from 50 amp to a 30 amp plug to power surge will it hurt it? Or do I have to buy a 50 amp power surge pls let me know I’m just a 3 rd year camper and still learning.

Lyle Peterson
4 years ago

On torque for lug nuts, most tire shops use an air impact driver. Some of them can produce up to 450 foot pounds of torque. The technicians have no idea what their impact driver produces but they run the lug nuts on up to the torque produced by the impact driver. This torque can be far above what is recommended for lug nuts. The technician then uses a click type torque wrench to “finish” tightening the lug nuts. It clicks at the setting but the question is really how tight is that lug nut. If the impact driver tightened the lug to 300 foot pounds the click torque wrench will certainly click at 100 foot pounds if that is what it is set for.

Over tightening lug nuts is dangerous.

Gary Machholz
4 years ago
Reply to  Lyle Peterson

Lyle, most shops now use torque limiting impact extensions. In fact, the shop where I go they look up the proper torque setting for every vehicle – because I watch them do it. You are correct, over tightening is dangerous and likely will warp brake rotors on passenger cars and light trucks. Not to mention it makes them nearly impossible to get off if you have a flat on the side of the road!!!

4 years ago
Reply to  Gary Machholz

A few years ago after retirement became bored and went to work at Walmart tire and lube. We looked up each vehicles specs and used the correct torque limiting extension to set each one . Then another tech would use the torque wrench to check each nut.By having a second person check it we tried to fix errors before they started

Joe Bulger
4 years ago

Mike, good advice on the torque wrench. When done using it and storing it away always return the dial to zero but not below. This takes all compression off the springs and inner workings and keeps the wrench accurate.

4 years ago

Any chance you could video your transfer switch and cord reel maintenance clinic? Something I am sure a lot of us that do not belong to that group would be interested in.

Mike Sokol
4 years ago
Reply to  Herb

I won’t be able to video that particular seminar next week, but I’m working on getting an overall sponsor so I can do more off-line videos on topics such as transfer switch and cord reel maintenance. The good thing is South Wire is giving me 3 of their transfer switches and a big 50-amp motorized cord reel to take back to my shop, so I’ll be able to play with them at my leisure. What fun!

Richard Palmer
4 years ago


Two might be appropriate if the Christopher is in a poor soil location. Some areas of the country (Florida I am looking at you) have such poor grounding characteristics that pits have to be dug and wire laid in them to get a the ohms low enough for a proper ground. One size does not fit all in this case. Just my two cents as a 30 year veteran of doing electrical work.

Mike Sokol
4 years ago
Reply to  Richard Palmer

That’s a good point. The latest code calls for performing a Fall-of-Potential impedance test on a single grounding rod, but since grounding rods are cheap (and earth impedance testers are expensive and time consuming) everyone just drives in 2 ground rods and ties them together around here.

4 years ago
Reply to  Mike Sokol

In the picture above, the ground wires are tightly coiled- looks techie but what you want is a straight piece with as few bends as possible.

Sign up for the

RVtravel Newsletter

Sign up and receive 3 FREE RV Checklists: Set-Up, Take-Down and Packing List.