Friday, December 8, 2023


RV Electricity – No~Shock~Zone by Mike Sokol – Issue 13

Issue 13 • December 2, 2018

Mike Sokol, editor

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.

Welcome …

Things are rolling along nicely this off-season, and many of the demonstration products I need for my 2019 RV electricity articles, videos and seminars have already arrived. Some of these demonstrations I can set up and begin running right now to gather data, while others will need to wait for the spring thaw, but there are lots of new things for me to write about.

As many of you are aware, I never write about things I don’t know, and I certainly won’t cut and paste marketing hype. When I say I don’t know enough yet, that’s exactly correct. If I don’t have a product in my hot little hands, all I can say is that a technology looks promising, but I can’t guarantee it will work. But once I do enough testing on a particular product, I can easily give it a Yea or Nay.

With that being said, I hope you all realize that testing takes time; time to form a hypothesis on a particular subject, time to gather the gear from the manufacturers while often telling them I could destroy their demo gear in the process, time to develop a test procedure that gathers useful data, time to gather that empirical data, and time to crunch the numbers to see if they prove my initial hypothesis correct then send it out for peer review. So if it seems like months between when I announce the start of a project and when I have an informed opinion, it really does take that amount of time. But I really enjoy doing this, and it’s quite possible that I’m the only guy on the planet who isn’t part of some marketing group that’s performing this level of testing. And you should see some of the new test and training protocols I’m developing. It’s going to get really interesting by the summer of 2019. I’ll keep you all posted in the meantime.

donateP.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.

Stray Voltage Patrol

Just how bad is it out there?

While many campgrounds seem to be doing the right thing and performing maintenance on their pedestals, some of them are waiting until something goes wrong to fix it or, worse, ignoring the problem. Let’s look at the example of Disney’s Fort Wilderness Campground I wrote about two weeks ago on RVtravel. Since I’m too far away for a quick day-trip, and Disney corporate won’t respond to my emails, I really don’t know if anything has been fixed.

Or how about this pedestal on the right? While this picture didn’t come from a Stray Voltage Patrol member, it’s just one more terrifying example of how bad some campground wiring is. And no, this one isn’t about a lack of maintenance, or even wear and tear. It’s about really poor installation practices that I can’t believe ANY inspector would have passed. And yes, that’s a water pipe running right through the middle of the electrical box. Read more.

Email me at mike (at) with your questions.

Industry Updates

The 2018 Ford F-150 Diesel offers 30 mpg and 440 lb-ft of torque

I admit to being in love with diesel engines, especially after driving my Sprinter van more than 300,000 miles across the country many times. While the truck manufacturers seem to be primarily involved in a max horsepower and towing war, there’s a subculture popping up of much smaller pickup trucks with mid-size (and horsepower) diesel engines. Even though my Sprinter with a 5-cylinder engine only had 154 horsepower, those are diesel horses which are measured and pull much differently than their gasoline counterparts. I could load my Sprinter up to 9,000 lbs. and blast across the country, even climbing rather steep grades out west while maintaining 70+ mph and getting an honest 24 mpg. Pretty amazing.

That’s why I think this latest offering from Ford, an F-150 pickup with a 3.0 liter V6 diesel rated with 250 horsepower, 440 lb-ft of torque and an 11,400 lb. towing capacity is really interesting, especially if you have to tow a small to mid-size recreational trailer. And with a 30 mpg highway fuel rating, this could be an affordable day driver as well. As promised, I’ve recently asked Ford to loan me a demo truck for the 2019 camping season, and if they come through with one, I’ll indeed drive it across the country towing a small RV trailer. But it’s slow going with these big companies, so I will have to update you all later. Wish me luck.

In the meantime, read more about the latest 2018/19 F-150 diesel HERE at Road & Track.

Survey Question

Would you be interested in a weekly or monthly newsletter reviewing emergency preparedness advice and tips, plus gear and supplies for your RV? 

Since dozens of you had to jump in your RVs and leave quickly from the California wildfires, and it seems like a major disaster is happening around the country every month or so (fires, hurricanes, floods, etc.), Chuck Woodbury and I are considering creating a newsletter of some sort that would review emergency preparedness tips as well as gear and supplies needed if you had to evacuate your house quickly, leave in your RV with your family and pets, and perhaps “boondock” for a few weeks or months until you have other options.

Last month’s survey results:

Click image to enlarge.

What do you want to know?

Well, this is interesting. Last month I asked what topics you would like to see included in my 2019 RVelectricity seminars, and the top one is how to use electrical meters. That’s easily the most advanced topic on this list, and fully one third of you (33%) selected it. That was followed closely by electronic gadgets (24%), which is another topic that can be technically challenging to teach.

What this means to me is that I can step it up a notch. While many of the other RV websites I frequent teach very basic topics (how to clean a black water tank, which is important but not very interesting to me, personally), you all want me to fire up my neurons and teach about meters and electronic gadgets. As the genie in Aladdin’s Lamp says, “Your wish is my command,”  so that’s exactly what I’m going to do. Look for more RVelectricity seminars from me on meters and electrical gadgets in 2019. I welcome the challenge!

Watch for my upcoming 2019 RVelectricity tour schedule, which I’ll release next month. Chuck and I are still working on sponsorships (want to get involved, please email me at so I can afford to do these seminars across the country. It’s slow going so far with not a single RV manufacturer (yet) willing to even pay for my gasoline and hotel rooms. I really want to teach, so please tell your RV industry friends that they should support my efforts.

Tools and Other Devices

You need a rechargeable weather radio

As I sit here there’s another cold front moving across the country and record snowfalls predicted. Last week it was the California wildfires and big rains coming with potential flooding.  Next week it could be most anything. I think that everyone needs some sort of weather radio that can help warn you of these weather-related emergencies so you can protect yourself and your family. And if it will run from a solar panel and hand-crank generator, in addition to AA batteries, so much the better. I’ve asked Eton to send me their latest model for review, but it hasn’t arrived yet. However, I think that their current model on Amazon looks like a good choice. Much more on this later, so stay tuned.

Last Month’s Posts

Generator neutral bonding basics.
30-amp to 50-amp generator connections.
Tired pedestals are dangerous.
How to protect yourself from ungrounded power.

The best book on RV electricity, hands down!
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 

Q&A’s from other forums

I spend a lot of time on dozens of other RV forums answering questions about electricity. Here is one really interesting topic that keeps on cropping up. Just how many amps can a 50-amp shore power outlet supply?   

From the Holiday Rambler Group:

Q: Mike,
Saw this page on the web describing a 50 AMP service. I have a problem with some of the wording saying that each leg is 50 amps at 120 volts.  That has made some RVers think they can run 50 AMPS on each leg. I think the wording should be clearer that there are only 50 AMPS total available not 100 AMPs.

What are your thoughts? —Dick K. / 2015 Holiday Rambler Ambassador 38DB

Read Mike’s Answer

Important topics from past issues

Why portable space heaters are dangerous. Learn not to burn!

It’s that time of the year again when the cold weather causes you to get out your portable electric space heaters. However, there have already been a few deaths from home fires in my area due to improper extension cords being used to run space heaters. Please take the time to reread and review these important safety articles, and remember to NEVER leave a portable electric space heater running unattended.

Electric space heater safety, Part 1

Electric space heater safety, Part 2

Let’s play safe out there….

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 – YWYD (You’re wasting your dad – Pass it on)

By Mike Sokol

I’m an adjunct professor at a music conservatory that’s part of a large university. And I get a lot of intelligent students in my audio electronics class, since they’ve already had to pass a number of juries in music performance and theory before they make it to junior level and into my class. So this really is the crème de la crème of students.

Since this is a practicum class (which means “hands-on”), I have my students build something as part of the class. In this case it needs to include soldering and basic assembly techniques.

But instead of having each of my students build individual kits, we decided to pool our resources and build one BIG kit. In this case it was a small guitar amplifier (5 watts), that the class would donate to the school’s recording studio once we finished it. This would be perfect for recording, and since each of the students would have a hand in building it, I felt the emotional ownership would instill a sense of pride, something that’s sorely lacking in many students nowadays. 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 2018 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.

Oldest Most Voted
Inline Feedbacks
View all comments

Heapie (@guest_37271)
4 years ago

Mike, many years ago, when I was an Inn Keeper, (1994 – 2012) I hoped to someday go back to RVing. When I was a college professor (1980 – 1993), I owned and used a Volkswagen Vanagon. Now rhat I am retired, I purchased a Roadtrek 190V, but found that it had poor sleeping arrangement for my wife and I. We sold it and are looking for a 190P.

All the time leading to retirement and purchasing an RV, I studied everything I could about the systems in an RV including your writeups at TravelRV. Every Saturday morning I read and studied TravelRV. I copied every chapter you wrote and put it into a loose leaf note book. Reason. You are the Captain of your ship. You are no different than a Captain of a Nuclear Sub, who has to know everything about all the systems on the Sub.

Keep writing. We all need to know about electricity.

Ron Lapierre (@guest_36892)
5 years ago

Don’t even have an RV yet (but working on getting there) but as a remodeling contractor, this newsletter is totally fascinating to me and I just wanted to tell you that you are a great teacher and I love the dedication you have. The article about YWYD was the best. I forget how much I know after 35 years in the business and though my son wants no part of the trades, I know there is someone else out there that I can pass it on to. Thanks for the reminder and your caring attitude. Keep up the great work.

Fox (@guest_36879)
5 years ago

Mike do you know if you can mix & match with generators? I mean can you parallel 2 different brands and outputs together?

John T (@guest_36873)
5 years ago

I voted “no”on the emergency preparedness survey because I’m a full-time boondocker, so I have no house to flee in the event of a disaster, and boondocking is not something I would do for only a few weeks until I had other options! I cannot think of anything better than being out in the boonies 365 days every year!

Mike Sokol (@guest_36875)
5 years ago
Reply to  John T

That’s the great thing about being a full-time boondocker. Wherever you go, there you are.

Larry M (@guest_36870)
5 years ago

Even though the receptacle found in your RV is rated at 120 VAC, the 50-amp shore power is actually a 120/240 VAC four wire service. The acronym VAC stands for “Volts of Alternating Current” which means the voltage is constantly changing from 0 volts up to 120 volts Positive back down to O volts, then it goes to negative 120 volts and then back up to 0 volts. This happens sixty times a second. This is commonly referred to as 120/240 VAC 60 HZ (Hertz).

The actual electricity that feeds your 120 VAC receptacle in your RV comes from your 120/240 VAC breaker panel. This panel is supplied with 240 VAC which is made of two 120 VAC legs that are 180 degrees out of phase. This means that when Leg-1 of the 120 VAC is going from 0 to 120 volts positive. Leg two of the 120 VAC is going from 0 to 120 volts negative.

To get 240 VAC for the larger appliances like a CheapHeat™ system, rather that going from one hot leg to neutral (120 VAC). Power is now taken from the two opposing hot legs and since they are 180 degrees out of phase, the end result is 240 VAC. Now that the neutral (white wire) isn’t used in the 240 VAC configuration.

Now let’s review the four wire 50-amp shore power cord, the cord we are talking about has four 6 gauge wires rated at 50-amps each. Which means the cord has two 50-amps legs at 120 VAC (Hot to Neutral) for a total of 100-amps at 120 VAC or one circuit of 240 VAC @ 50 amps (L-1 Hot to L-2 Hot), or a combination of the two.

Wait! If we have 120 VAC @ 50 amps on the Red to White and 120 VAC @ 50 amps on the Black to White, wouldn’t that be 120 VAC @100 amps on the White wire since there is only one white wire? No it won’t, because the two hot legs are 180 degrees out of phase. When Leg-1 electrons are moving towards Positive 120 volts the Leg-2 electrons are moving towards Negative 120 Volts. This means that when correctly wired (phased) the Neutral leg will see no electron flow, that’s why it’s called the Neutral Leg, thus no overload.

******* DANGER ******* DANGER ******* DANGER *******

If the RV park pedestal isn’t wired correctly, and the two legs are not out of phase, you will have 100-amps applied to the white wire that is only rated for 50 amps. In that scenario you have both Leg 1 and 2 electrons moving towards 120 volts positive and then negative at the same time. Which means you have double the electron flow (Current) going through the white wire when it’s only rated for half that load. End result is an overloaded wire that will overheat and very possibly cause a fire.

How do you know when you have an incorrectly wired Shore Power Pedestal?

There are two simple ways, one is to install a surge protector that identifies incorrect phasing and locks out the power to the RV. The second way is to use a simple voltmeter that is rated to test AC voltage up to 300 volts. If the pedestal is wired correctly when you test from Leg-1 to Leg-2 (not Neutral) and the two legs are 180 degrees out of phase as they should be, the meter will read 240 VAC. When the Shore Power Pedestal is wired incorrectly, the two legs are at the same phase. Then the test from Leg-1 to Leg-2 (not Neutral) will read 0 volts on the meter. As stated previously, this is an unsafe condition because you can have a 100 Amp load on a wire that is only rated for 50-amps. All of that being said this means that using a 30-amp to 50-amp pigtail adapter will NOT allow you to see 240 VAC in your breaker panel. Because in that scenario your just splitting the same single black hot leg on the 30 amp plug to feed both the red and black on the 50 amp plug.

Its also important to note, that their CheapHeat™ Electric Hybrid Furnace kit is designed so that when it is configured to operate on a 50-amp service, it is not subject to these types of overload problems. Along with its inherent phase protection, it also has multiple high temperature safeties to protect from any overheat conditions. It is also hard wired directly into the main power system of the RV removing the potential fire hazard that can happen when plug in portable electric heaters are used. For more information about their product you can go to or call Ph.# 425-408-3140.

Claude Comeau (@guest_36842)
5 years ago

Mike another question, in my 30 amp MotorHome do I have 2 legs of 30 amps. If so how can I determine what circuits each leg feeds?

Mike Sokol (@guest_36843)
5 years ago
Reply to  Claude Comeau

Claude, no there’s only one leg of 30-amp in a TT-30 outlet. So that’s 30 amps x 120 volts = 3,600 watts total. But the 50-amp NEMA 14-50 outlet works out to 50 amps x 2 legs x 120 volts = 12,000 watts. That’s why there’s such a big step up in available power (wattage) from a 50-amp shore power outlet compared to a 30-amp outlet. Power (wattage) is everything, as they say.

Claude Comeau (@guest_36841)
5 years ago

Mike great work here. In my 30 amp MotorHome, is each plug in the kitchen area on it’s own circuit breaker, as it would be in my house? TKS!

Mike Sokol (@guest_36844)
5 years ago
Reply to  Claude Comeau

No, in an RV there’s typically a single 20-amp circuit breaker that feeds the first GFCI outlet, which then feeds all the other kitchen and bathroom outlets. So you’ve got 15 or 20 amps total on that branch circuit (depending on what size circuit breakers is in your panel). This is totally different than house wiring where by code you have separate 20-amp circuit breakers for the bathroom, kitchen, bedrooms, basement, and lighting. Because there’s such limited power in an RV shore power connection (30-amps is the same wattage as 1 and 1/2 outlets in your house), you have to be careful to monitor your power usage. That’s just how it works.

Sign up for the

RVtravel Newsletter

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