Friday, December 8, 2023


RV Electricity – No~Shock~Zone by Mike Sokol – Issue 33

August 2, 2020 

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Welcome …

By Mike Sokol

Testing, Testing, 1… 2… 3…

Yes, this is indeed the summer of testing and discovery for me. Since the start of my “soft” retirement last year, I’ve been backing out of my regular day jobs that I don’t want to do anymore, and ramping up the projects that I really like to work on. And two of my favorite projects are building new electrical gadgets and testing things.

This is full circle back to my early engineering days in the ’70s when I was doing industrial power and robotics design for a large packaging plant, and the ’80s when I was building and testing components for nuclear missile guidance systems. At first blush neither of those jobs seem related to the RV industry and electrical safety, but they actually are exactly on point. For starters, campgrounds have electrical distribution systems on the same scale as an industrial building, with many similar issues.

Part of my job back then was training the plant electricians about electrical safety and best practices. That’s also when I was schooled by the then-new Occupational Safety and Health Administration agency (OSHA) on topics such as PPE (Personal Protective Equipment), Arc Flash dangers, and regular testing of safety equipment such as eye wash stations, lock-out/tag-out, etc… I also learned a lot of shortcuts that electricians would sometimes try to take which could be dangerous. Sound familiar?

On the other hand, RV electrical systems have some of the same issues as the nuclear guidance systems I built and calibrated in the ’80s, where voltage calibration is critical to operation, poor connections can lead to product failure (as in missiles blowing up mid-launch), and learning how to measure things down to 6-decimal accuracy helps explain what’s going on under the hood.

You’ve probably already read about HRDL (High Rate Data Logger) – rhymes with “turtle” – which I designed and built last month out of extra parts laying around in my shop. With a few tricks I learned in the ’80 from calibrating the Digital to Analog converters on missile guidance systems, I can now see exactly how various electrical devices in an RV work and interact with other components, logging this highly accurate data hundreds of thousands of times a second and displaying it in easy-to-understand graphs.

This level of data gathering was nearly impossible 40 years ago when I was doing it for military components, and even now would cost around $100,000 in test gear. But I built HRDL for a few hundred dollars worth of spare parts I already had laying around and a week or so of prototype time in my small lab.

I do feel pretty good that the things I learned in the ’80s as a way to launch nuclear bombs, which could have destroyed the earth, I can now use in my peacetime efforts to help build things like better RV battery management systems, or learn how to start an RV air conditioner more easily, or evaluate Hughes voltage boosting transformers for National Electrical Code compliance.

So when I say I’ve tested something, you can rest assured that I’ve done this to the current state of the art, and sometimes a little better. Some of the RV manufacturers are now beginning to ask for my suggestions on wiring issues, which is great. And if my OSHA safety grant is awarded in September, I’ll be able to begin teaching campground technicians better ways to safely test, maintain and repair campground pedestals and their local power distribution.

So please stand by for even more RV electrical information this year and in 2021. I’m just getting started….

Let’s play safe out there… 

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.

If you haven’t yet, be sure to join
my Facebook group, RV Electricity.
(More than 9,500 members and counting.)

Testing Autoformer theory of operation

Mike Sokol to begin lab testing of Hughes Autoformer

Okay, folks… My lab is now set up to determine exactly how a Hughes Autoformer interacts with campground power when it boosts low pedestal voltage by 10%.

As you may have read by now, the National Electrical Code® (NEC®) has declared any transformer in a campground a code violation as of the 2020 edition because it draws more current from the pedestal to boost the voltage at the RV. However, Hughes wants to fight back, stating that their product will actually help reduce extra current draw from an air conditioner enough to offset the other current increases. So who’s right and who’s wrong? I’m not sure, but I’m doing a test next month that should prove or disprove the parties’ assertions. Read more HERE.

Email me at mike (at) with your questions.

Watch Mike’s webcast seminars 
• FMCA – RVelectricity Basics Part 1 – Part 1 includes volts, amps, watts, and how to use a digital meter to measure them for your RV.
• FMCA – RVelectricity Basics Part 2 Mike covers the basics of campground pedestals including the use of EMS/Total Protection surge protectors. He also covers potential sources of electrical fires in an RV and ways to prevent them.
• FMCA – RVelectricity Basics Part 3 – Mike discusses portable generators, DC-DC charging systems, and lightning protection in a campground during a thunderstorm.

RV Propane/LP Gas Alarm may save your life
This Safe T Alert Propane/LP Gas Alarm is designed specifically for your RV. It features advanced technology with an “Alarm Mute” button that silences the alarm when the RV is ventilated and a rapid recovery sensor that resets when silenced or reactivates if dangerous levels of propane remain. An easy 12-volt installation means there will be no missing or dead batteries to replace. Learn more or order.

Industry Updates – An RVelectricity test

Proper campground load balancing might be able to boost pedestal voltage by 5% with no cost to the campground except for labor

I had a dream about this last month after receiving dozens of emails about voltage differences on either side of 50-amp pedestal outlets. There’s a simple rewiring trick that campgrounds could do that would not only balance this voltage, it could also reduce the overall voltage drop and lost wattage in a campground distribution system by perhaps 5% or more. If my hypothesis is correct, then a campground with voltage that drops down to 105 volts in the afternoon could be kept up at 110 volts. Yes, there is such a thing as a free lunch if you were throwing away half a sandwich all this time.

No new wiring or transformers are needed to make this happen, just a re-balancing act that would take a campground electrician less than 30 minutes for every other 50/30/20-amp campsite pedestal in the campground. I’m sure this will be effective at some level, but just how much it will do to restore low voltage in brown-out conditions is the question. I’ve got my money on 10%, but even a 5% boost in voltage would be worth the effort, and it could result in lower electrical bills for the campgrounds as well. Talk about win-win.

Testing my hypothesis at a large campground has already begun. I’ll know more next month after phase 1 is complete; but if I’m correct this could really help increase low campground voltage and reduce distribution losses. So cross your fingers….

Read more about it next week in my RVtravel column.

Survey Question

What’s the lowest voltage you’ve ever experienced at a campground?

Feel free to leave a comment.

Stay organized like Mike!
Here’s a tip from Mike about staying organized: “After one more frustrating dive to the bottom of my ‘battery drawer’ looking for a few AAAs to power my latest gadget, I’ve decided to get organized. This holder should keep you stocked with enough batteries for an entire camping season, and even includes a nice tester to find the dead ones. Also, you all know not to just throw used (or new) 9-volt batteries in a drawer where they can make contact with metal objects and catch on fire, right? Here’s what I’m ordering to keep it all under control.”

Last month’s survey results:

Do you bring along a portable generator or use an onboard genny?

Well, Power to the People, as we used to say back in the ’60s. A whopping 86% of you either bring along a portable generator or use an RV onboard generator. I guess we’ve all become so dependent on electrical power that relying on batteries or solar panels alone won’t cut it for camping. And I certainly don’t trust campground power to be 100% reliable. So, generators it is, which are probably needed because so many of you have 1, 2 or 3 air conditioners in your RVs. It’s come a long way since my Cox popup camping days back in the ’60s with a white-gas Coleman lantern.

Tools and Tests

Watch this short video showing my advanced HRDL demonstration of the SoftStartRV unit. I’m now setting up HRDL data logging for my Hughes Autoformer tests next month.

Watch HRDL in action HERE.

Keep mice out of your RV
The positive reviews on this product from Earthkind make it the best bet for keeping your RV mouse-free. It’s the only plant-based rodent repellent registered for inside use by the EPA. It effectively repels rodents up to 90 days with a “woodsy” scent that’s pleasant to humans but offensive to rodents. It’s safe around kids and pets, too. 98% biodegradable. Learn more or order.

Last Month’s Posts

These articles are rated Moderate to understand for most RVers

Get yer red hot projects right here, folks….
Swimmers electrocuted in Arizona lake. Don’t let this happen to you!
Hughes Autoformer – A cure for low campground voltage?
SoftStartRV update – Yes, it really works, and here’s proof
New non-profit RV electricity association.

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

These articles are rated Easy to understand for beginners

Please buy a digital meter.
Keeping cool without an AC.
Chiller? Cooler vs. refrigerator comparison.
Electric Shock Drowning Warning.
Pedestal readings for 50-, 30- and 20-amp outlets.

Boondocking Power Requirements – Part 2

The refrigerator question…

Boondocking isn’t as simple as just parking your RV in the woods. It’s easy to forget just how much power we use in an RV. And while I don’t have an easy solution for running a rooftop air conditioner from solar panels and batteries (just yet), I have learned a few things about refrigerators in RVs over the last year – which is the topic of Part 2 of this series.

Sponsored by CarGeneratorTM .

Read More HERE.

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 

Mike’s Video Quick Tips

How to measure AC voltage with a meter – 4 minutes
How to measure 30-amp volts WITHOUT a meter – 4 minutes
How to properly torque screws in a transfer switch – 4 minutes

Road Signs Retread

By Mike Sokol

Peripheral Visions

I have learned from a lifetime of misplacing objects that often the best way to find something is to not look for it directly. Seems counter-intuitive, but it’s true. I’m the quintessential absent-minded professor who sets down the screwdriver already in his hand while searching for a wrench, only to lose the screwdriver in the process. Then I’ve got to look for the screwdriver without losing the wrench again. So you can see I’ve had a lot of practice looking for lost objects…

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.

For information on how to support RVelectricity and No~Shock~Zone articles, seminars and videos, please click the I Like Mike Campaign.


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

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Bruce Siceloff (@guest_94695)
3 years ago

I would appreciate advice on installing a backup camera for my 2014 13′ Scamp. I bought a LeeKooLuu 1080P Wireless. Instead of installation instructions they point you to a cryptic video. Thought I understood how to splice into the trailer’s backup light (using T-taps) (so the camera would turn on when I shift into reverse). Instead, I apparently killed the backup lights, and the camera doesn’t work. Maybe I spliced wrong? Maybe I handled the ground wire wrong? 

Leon (@guest_89726)
3 years ago

I have always thought of current increase in a motor with a low input voltage as if the motor is forced in a partial start up loop. Your hrdl picture shows a perfect example (actually two) of the increased current draw when the motor is starting (running at a slower speed similar to having a lower input voltage).

Joe (@guest_89651)
3 years ago

One time in Canada after being plugged in for several hours one leg of the 50 amp receptacle went to 137 volts at about 8PM kicking off my smart surge protector. My theory is that somewhere along the line there is a transformer with a high tap leg and when the local business and manufacturers shut down the voltage would tend to go up. Happened 2 nights in a row, lucky the 30 amp was a steady 120 volts, I had to prove it to the maintenance staff that my and other pedestals were experiencing the same issue which they did not understand. Made me question how many people out there that are not using a smart surge protector.

Charles (@guest_89627)
3 years ago

Can I use a 50 amp adapter to my 30 amp RV cable? Is there any advantage to doing this rather than just using the campground 30 amp outlet?

Joe (@guest_89654)
3 years ago
Reply to  Charles

I’m not sure they make one. You now have a 30 amp #10 wire being protected by a 50 amp breaker, you would more than likely have a fire before you would trip the breaker. The 50 amp receptacle is protected by a double 50 amp breaker, a 30 amp receptacle is protected by a single 30 amp breaker. It’s kind of like trying to put the round peg in the square hole.

Ed D.. (@guest_89764)
3 years ago
Reply to  Charles

I have a 50 amp adapter just in case the pedestal doesn’t have a 30 amp outlet.

Curt Coffee (@guest_89537)
3 years ago

Good post and thank you

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