Saturday, September 23, 2023


RV Electricity – No~Shock~Zone by Mike Sokol – Issue 24

Issue 24 • October 27, 2019

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Welcome … to Issue 24

By Mike Sokol

WOW! So it’s been two years since I started writing this Sunday newsletter, and in that time it has grown to more than 15,000 readers. And my Facebook RV Electricity group now has more than 4,000 members. That’s a double WOW, at least! And in that time I’ve learned a few things about you, my readers, that I didn’t know or was only peripherally aware of.

First, I’ve discovered that I have a lot of very smart readers. While many of you are real newbies and never touched a digital meter before you bought an RV, there are dozens (perhaps hundreds) of you who are totally up to speed on electricity including Electrical Engineers, Master Electricians, Journeyman Electricians who run power lines, Ham Radio Operators, System Design Engineers, RV technicians, etc.

And there are many readers who are professionals and tradespeople who just haven’t learned about electricity yet, but who know how to learn things. That includes hundreds of readers who are active and retired doctors, lawyers, chemistry teachers, firefighters, OTR truck drivers, pilots, AV designers, chefs, musicians, nurses, and lots more of you who want to learn about electricity for both your RV and your own home or business. So that’s a triple WOW!

Second, there are a LOT of generous readers who heard my call for monetary support last month, and have donated to my I LIKE MIKE campaign. Hundreds of you have donated so far, dozens with automatic monthly pledges.

Yes, I do receive 100% of those donations, except for the piece the IRS will take at the end of the year. Your support to date has been far what I imagined, and it inspires me to work even harder to serve you with information that is not easily available elsewhere, yet critical to you to keep you and your RV safe. Here’s a great big THANK YOU!!!

So please keep up your support whenever you can, because I’m building some really cool demonstration tools for 2020, the likes of which have never been seen before in an RV seminar. And you know that I never exaggerate about such things.

Third, as I’ve mentioned in an earlier newsletter, the comments of encouragement from you all have been fantastic. Sometimes it feels like I’m teaching in a vacuum, which is why I’ve started doing live seminars around the country. I’ve only done a dozen or so RVelectricity seminars in 2019, but 2020 could be really big as I’ve already been asked back to Hershey 2020, RVillage, Airstream, FROG, FMCA, and a dozen more. So if managed properly I could double my seminars in 2020. Hope to see you at at least one.

Fourth, lots of you are asking for more video training, so I’m setting up to do that over the winter months. I’ve dabbled in video over the last year, but now I think I’ve got a production formula that will work out for everyone. And I’m keeping all consumer-level online training videos free for you, while beginning to charge RV manufacturers and technicians for deeper level training.

Finally, I now have some traction with several of the RV manufacturers who are discussing monetary support for me teaching RV technicians at their dealerships around the country. That’s right, if all goes well in 2020 I’ll begin to improve the troubleshooting ability of RV technicians around the country. I can hardly wait. Really…

As I’ve written many times before, I believe that teaching is one of the most important and rewarding professions one can do, and it’s my privilege to teach you all about electricity. So when I say that I want To Serve Man, I’m not talking about a cookbook like in my favorite Twilight Zone Episode. But I digress….

So buckle up. We’ve got some interesting things to cover in this newsletter. Yes, here’s one final WOW!

Let’s play safe out there… 

If you haven’t yet, be sure to join the popular and informative Facebook group, RV Electricity. (More than 4,000 members and counting.)

Generator automatic transfer switches 101

As promised, here’s a look at how your generator automatic transfer switch (ATS) works, and how to troubleshoot it when it’s not working properly.

But first, a few definitions:

ATS is an abbreviation for automatic transfer switch, and its job is to be a traffic cop between the pedestal shore power and your on-board generator power.

Read more.

Email me at mike (at) with your questions.

RV Electrical essentials
Surge ProtectorsDogbone Electrical AdaptersMultimetersPower Pedestals for Home or Campgrounds. • Portable GeneratorsRV SolarRV InvertersRV LED Lights30 and 50 amp extension cords

Watch Mike’s one-hour recorded webcasts
All about portable generators. Recorded May 19, 2019
RV power pedestals: what you should know. Recorded May 10, 2019

Industry Updates

WAGO connectors could become an industry standard

After my article a few weeks ago about an improved wire splice system that could eliminate wire nuts in RVs, I was contacted by Progressive Dynamics, who offered to send me one of their new power distribution panels with WAGO connectors instead of standard screw-terminal strips. According to a field engineer there, this spring-loaded design could eliminate screws loosening up from road vibration, or improperly installed wire nuts, which are likely the reasons for many failed and overheated connections in RVs.

Read more.

Survey Question

Do you use any sort of surge protector or EMS to protect your RV?

Last month’s survey results:

Click to enlarge.

Has your RV been in the shop for electrical repairs?

Since the topic of how long RV electrical repairs take is a favorite one, I decided to ask that simple question last month, and here are the results.

While 81% of you didn’t require any RV electrical repairs (which is a good thing), 13% of you who answered the survey said the repair was done in a week or less. However, 3% took up to a month for repair, 2% took months, and 1% of you said your RV had been in the shop for months for an electrical repair and it still wasn’t fixed.

However, if you normalize the survey to compare only those who needed electrical repairs, that jumps the percentages up to 65% of those responding were fixed quickly, 15% took up to a month, 10% took months to be repaired, and 5% were still in the shop for months without being repaired. If the auto industry had those kinds of repair numbers, there would be a lot of wailing and gnashing of teeth, but the RV industry seems to accept that as normal.

Well, this is just one more reason for me to begin teaching advanced electrical troubleshooting classes for RV technicians. As noted in my Welcome letter above, I’m finally getting some traction with the manufacturers to support my training efforts for their dealer technicians. Let’s hope it really gets going in 2020.

Shore Power Maintenance

Don’t let loose or corroded connections stop your party in its tracks

I’m often getting questions like this one asking about why shore power plugs can get hot and melt. Here’s a basic tutorial on what to watch for, and simple maintenance steps you can perform to help keep your shore power cords and connectors happy (and not melted down).

Read more.

Last Month’s Posts

These articles are rated Moderate to understand for most RVers.

No~Shock~Zone Part 8: GFCI Theory.
Space heater warning – 2019.
Inverter generator battery charging.
Torque those ATS screws properly.

Last Month’s JAM (Just Ask Mike) Session posts:

These articles are rated Easy to understand for beginners.

Leggo my WAGO… Mike explains why the WAGO 221 lever-action splicing block could be the greatest innovation in wire splicing technology since the invention of the wire nut.
Predator parallel generator power. A reader questions the power produced by parallel generators compared to what’s claimed in their ad.
What are inverters and converters?
What is an RVelectricity™ Master Class?

Tiny LED button lamp perfect for RV’s small, dark spacesRV Travel Newsletter Issue 913
This 6-pack of tiny, battery-powered LED “Button Lamps” is just what you need for your RV’s closets and storage spaces. The tiny lamp is ultra-bright and has all the power of a normal-sized lamp. Backed with a strong adhesive, these little lamps will stick to any surface. They’re waterproof and good to have in case of an emergency. Learn more or order.

Q&A’s from my Facebook group:

I’m getting a lot of interesting questions on my RV Electricity Facebook Group. Here is a good one:

Q: We are having a soft start installed on our new camper before pick up. Can someone tell me how to test this to make sure it’s working properly? I have one of the meters that has the clamp. Can you clamp it around the main power cable into the trailer to see the amp spike when you turn on the air conditioner?

A: There are two things you need to measure the starting current of a motor.

First, you’ll have to have a peak-hold clamp ammeter. As others noted in the group comments, a regular meter won’t show the peak current long enough on screen to be useful, so you’ll need one specifically designed to measure inrush currents. Some of my really expensive ($500+) meters do this, but with a little Amazon searching I found a clamp meter with inrush current function for less than $40. While I can’t vouch for the accuracy of this meter, it does look pretty good at first blush, and might be just what you need for testing. Buy it HERE.

The second thing you’ll need is some kind of line splitter to separate the hot and neutral wires on your shore power for doing the measurement. That’s because if you clamp around the entire cord, the outgoing current on the hot wire and incoming current on the neutral wire will cancel each other out and read zero, no matter how much amperage is flowing.

You can make one of these by carefully slitting off the jacket of a short extension cord and separating the black or red wire out of the bundle. Or for quickie testing you can use a 15-amp dogbone adapter plugged into one of these line splitters. Yes, it will carry the 20 amps of current temporarily for testing, but you won’t want to run your entire RV off of one of these – only turn on the air conditioner that you’re testing to get the peak current measurements. You can buy it on Amazon HERE as well.

Email me at mike (at) 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 50+ 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

Did you miss this morning’s RV News newsletter?

RV Travel Newsletter Issue 919If so, here is what you missed:
• Major RV retailer put on bankruptcy danger list.
• Your chances of dying in a vehicle crash have gone down a bit.
• Homeless “RVers” in Northwest dumping a million pounds of raw sewage into local waters.
• Another good reason to keep your RV fully “ready” as a self-contained unit.
• Two teens die from carbon monoxide poisoning in trailer during power outage.
: Latest fuel prices • Upcoming RV Shows • Latest RV recalls • Free and Bargain Camping locations. Plus a reader survey.

Read the issue.

Camco Store at
There isn’t much you need for your RV that Camco doesn’t have. 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 –
Keeping it simple is hard to do…

By Mike Sokol

“Everything should be made as simple as possible, but not simpler.” —Albert Einstein

To be successful at teaching potentially complex subjects, it’s necessary to break them down into the smallest possible elements, then build from there. And to do that I spend a lot of time with thought experiments. These are little mind games I play in my head about possible ways that things actually work. Read more.

Let’s play safe out there….

Mike Sokol is an electrical and professional sound expert with 50+ years in the industry. His excellent book RV Electrical Safety is available at For more info on Mike’s qualifications as an electrical expert, click here.


Editor and publisher: Mike Sokol with the assistance of Diane McGovern and the helpful staff of

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.

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  1. Hello Mike! Thanks for all the wealth of info you provide to all of us.
    My subject has to do with my 10 gallon Atwood gas/electric water heater (GC10A-4E) in my Holiday Rambler Class A motorhome (30-amp service). I have had the circuit board replaced several times in the last two years. The water heater is working when plugged in to electricity and after a few days of boondocking on gas will stop working. I can bypass the circuit board and the gas water heater will fire up just fine. I can’t keep replacing circuit boards. Do you have any recommendations as to what could be causing the circuit boards to keep going out when on gas (gas still requires a 12-volt electrical operation to function)?
    I should mention that on a 3-month trip last fall my wife accidentally ran our two A/Cs at the same time (30-amp service and only supposed to run one-at-a-time), this resulted in frying one A/C, the compressor going out on the other a week later, a fried transfer switch between rear A/C and microwave, and the water heater to not work as it was set to electricity at the time (probably not actually operating as the water was already hot). A few weeks later we experienced the melting of the 30-amp motorhome plug to the EMS plugged into the current RV park’s pedestal (we were moving to new locations almost daily as we traveled across the country).
    Everything has been replaced (2-new A/Cs, the transfer switch and the hot water heater circuit board, all by professional RV shops) and yet we still keep loosing the hot water heater and replacing the circuit board for what turns out to be a short term fix. What are we or the RV shops missing? I’ve spent more money fixing this hot water heater than if I would have had I just had a new hot water heater put in and I’m now thinking about having that done. But, I don’t want to do that if the problem is actually somewhere else contributing to the repetitious failure. (Bottom line is keeping my wife happy and I need everything to work correctly (you know, the luxuries of home) and to do this as the RVing is my thing and this is how I can keep my wife happy “camping” while we travel.)
    Any words of wisdom would be greatly appreciated. Thank you!

    p.s. I’m on circuit board #5 (counting the motorhome’s original and one factory defective one).

    • I’m going to post this over to my Facebook RV Electricity group for a little crowd sourcing and see if we can come up with a possible cause. Do you have a meter and have you checked the voltage on your 12 volt system?

      • Yes, I have a meter but I have not checked out the voltage of the 12-volt system with it. But, I have a DC plug in that I have used to plug into the 12-volt system accessory plug setup that shows digitally my batteries voltage and that is fine. BTW, when boondocking I’m all solar with four 6-volt batteries and a 305-watt solar system. I have no problems with plenty of 12-volt power.

        I’ll now go over and find your Facebook RV Electricity group.

        Thanks Mike!

  2. I am amazed that there is discussion about wire nuts in an RV. Wire nuts should only be used in a stationary building. They are not sufficient for anything vibrating down the road. Crimp or mechanical connections should always be used in a vehicle.

  3. Mike I’m a bit set off by campground electric pedestals. The 30 amp receptacle are worn out . And actually the state parks are the worst. So far some deoxit has got me through. Considering a built up 30 amp adapter ( a silver solder build up on the blades of the plug) to plug into the pedestal to make better contact.
    Thanks for what you do

    • You’re very welcome. By coincidence I was just in the Maryland state park office this morning asking about any resources that would show what kind of campsite power was available in the 36 state parks, and they couldn’t find any comprehensive data for the state. They suggested I contact or drive to each state park for clarification. Ugh! From what I can see, there’s over 400 state parks in the USA, so calling or driving to each one would be crazy. But I’m working on it…

  4. Hi Mike,
    I sure wish you would come down to the 2020 Tampa RV SuperShow in January and do a talk. They have nice facilities for lectures.

    • I’ve snooped around but haven’t gotten in invite from them yet. I’ll try again next week. Does anyone have any contacts at the Tampa RV Super Show?

  5. Mike, I am fairly new to RVing (two years) and I am an engineer who is familiar with electrical circuits. When I bought my RV, I also bought your book and learned a lot. I had an incident about 1 year ago which involved electricity that I want to tell you about (because it is a problem in many newer RVs). My auto leveling system started to cut out and I would need to reset it. This became more frequent until near the end of one trip it wouldn’t work at all (wouldn’t retract the slides or the jacks). I called the RV manufacturer who couldn’t figure out why I had the problem and referred me to Lippert (manufacturer of the the leveling system). The tech there told me to run a voltage check on the automatic circuit breaker on the electrical line to the hydraulic pump which drives the slides and the leveling system. I checked the voltage ( 13.7 volts in, 0 volts out). He told me my circuit breaker was faulty and needed to be replaced. He said it was an 80 amp breaker. I manually retracted the slides and the leveling system and returned home. When I removed the breaker I found it to be a bimetallic strip type that would break the circuit when too much current tried to pass and restore the circuit when it cooled back down. The contacts in the breaker were totally fried and a portion of the housing was melted. However, I saw that it was only a 50 amp breaker. I took it to the dealer where I bought the RV and told them I needed an 80 amp breaker to replace this 50 amp breaker. They told me they were all out of 80 amp breakers but would have a new shipment in a couple of weeks. (They had been replacing so many). I eventually got the replacement 80 amp breaker and it has worked fine ever since. But why did this happen. I spoke again with the Lippert tech and he told me the hydraulic pump can easily pull 80 amps or more. He said that many RV manufacturers upgraded their hydraulic systems about a year earlier but many had not upgraded their breakers (kept the old 50 amp breakers) and were now having problems. I asked if I needed to upgrade the wires going from the batteries to the pump. He told me that they should be adequate and when I checked their size and current capabilities they were adequate.

    This incident showed me a couple of things. First – RV manufacturers were aware of the problem but had not done a recall and replaced the breakers but were waiting until they failed. Those who didn’t use their RVs much would find they were out of warranty before the failure. Second – 80 amps is a huge amount of power (even for short periods of time of a couple of minutes). These breakers were heating up to extreme temperatures if they fried the contacts and could have been a fire hazard. RV owners should be aware that some of the circuits in their RVs can use large amounts of power (more than the 50 amps at the pedestal) which is DC power from their batteries. (You can’t draw more than 50 amp ac power or you will trip the breakers at the pedestal but you can draw more than 50 amps dc power from your batteries – my batteries are rated for 450 amp hours).

    Like you always say Let’s keep it safe out there.

    Jim Larsen


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