Issue 21 • July 28, 2019
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By Mike Sokol
While I was going through back issues of my No~Shock~Zone articles updating and republishing my original 12-part series on RV Electricity, I discovered something really interesting. Next year will be my 10th anniversary of writing electrical articles for the RV industry. All I can say is, WOW!
Seems like only yesterday that I started Googling about hot-skin conditions and hooked up with Gary Bunzer (the RV Doctor), and he said there would be only one e-zine producer he could recommend who would be fearless enough to publish what I was writing about RV Electricity – and that was Chuck Woodbury from RVtravel.com. Yes, even when the RV industry told me I was rocking the boat and scaring everyone away from buying an RV that could “shock” them, Chuck told me “full steam ahead,” and don’t worry about any naysayers.
In fact, Chuck has been one of my biggest cheerleaders and lab rat, both at the same time. You can guess what the cheerleader part is, but the lab rat moniker may require a little explaining.
Chuck reads everything I write and gives me feedback if I’ve gone too far without explaining myself first. And that’s an important function, since I normally teach at college level and even provide consult to manufacturers on product design. The real trick is to take what’s actually a really complicated topic and boil it down to the fundamentals that anyone can understand. It’s not easy, but that’s exactly what I’ve been trying to do for the last 10 years.
Now it’s time for me to take what I’ve learned about teaching you all about electricity and turn it into more seminars and videos. Yes, I’ve dabbled in both over the last year, and they’ve been working pretty well. In fact, my RVelectricity seminars have been getting a full house in many rooms, with top attendance for an RV rally or show. And I thank you all for that. Without your questions and feedback I might as well be teaching on an island. But add comments, both in a seminar and in these articles, and I instantly know if I’m getting through to you or just spinning my wheels.
So my big project for my 10th anniversary in 2020 is to get ALL of my RVelectricity articles into one place (RVelectricity.com), and develop a simple way for readers to find everything I’ve written on dozens of topics that you might not even know the name of. For example, I had to invent the term Reverse Polarity Bootleg Ground (RPBG) when I discovered a very dangerous miswiring condition that no tester on the market could discover. And I found that a Non-Contact Voltage Tester (NCVT) would indeed discover an RV hot-skin condition down to 40 volts or so, right at the danger level where electrocution could occur. And on and on it goes.
I’m currently doing all kinds of experiments with inverters and seeing how low voltage affects air conditioners and residential refrigerators. When I say I’m having “too much fun,” I really do mean it’s a lot of fun for me to do this.
In the coming months I’ll get all the bits of this pulled together, and then I just have to put in the hundreds of hours needed to organize my articles in a way you can better utilize them. And I’ll include a test section that will allow me to see if what I’m doing works.
I’ve always felt that the failure of a student to learn is actually the failure of the teacher to teach. So please let me know if my teaching style works for you. If not, tell me and I’ll adjust. And please let me know if you’re part of any Rallies or Expos in 2020 that can host one of my RVelectricity Seminars or Master Classes. I really do love the direct feedback I get from a room with 100 or more students. Yes, that’s also too much fun!
Seriously, it really is my privilege to teach you all about electricity, and I sincerely thank each of you for taking the time to learn from me. Let’s hope the next 10 years is just as exciting for all of us as the last 10 years have been.
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 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 new Facebook group, RV Electricity.
(More than 3,000 members and counting.)
12-volt DC electrical systems
How to install a disconnect switch for 1-, 2- and 4-battery systems
I’m a paying member of RVtravel.com because I appreciate the hard and honest work you and Chuck do. Thank you. In your newsletter #20 you talked about disconnect switches and said you would do an extended article on the subject in a few weeks. Not sure if you have or I missed a newsletter, but I’m interested in a wiring diagram of two 6-volt batteries in series and connecting a disconnect switch. I have a 2-post on-off switch. Do I disconnect the negative cable that goes from my trailer frame to my battery and connect it to one post on the switch, then take another cable, connect it to the 2nd post and run this cable to the negative post on the battery? —Mark Eddy
Ah, yes. The series/parallel battery question about where to place the disconnect switch. But before we get into the details, let me first give you all a few precautions when working around 12-volt DC power, especially when you’re moving battery terminals around.
Email me at mike (at) noshockzone.org with your questions.
Watch an electric Ford F-150 tow more than a million pounds
Ford is trying to show its rabid pickup truck fans that EVs aren’t just for latte-sipping Tesla pilots. In an impressive demonstration of torque, an electric F-150 prototype towed 10 double-decker rail cars stuffed with 42 current-model F-150s, weighing over a million pounds (500 tons) in total. That shows promise that it could beat Ford’s current towing champ, the 2019 F-150 with a 3.5L twin-turbocharged V6, that’s rated to tow 13,200 pounds (6.6 tons).
Read the full article HERE.
Let me note that pulling a million pounds of rail cars has little to do with just how much your truck can safely tow. However, this publicity stunt demonstrates that the major truck builders are beginning to think seriously about all-electric vehicles. It’s just a matter of time before they’ll be here. —Mike
Have you ever experienced a burned shore power plug?
RV Electrical adapters at Amazon. Big selection, great prices.
Last month’s survey results:
Do you have a digital clamp meter?
This was certainly an interesting survey. It appears that 25% of you have a digital clamp meter and know how to use it. That’s great, because clamp meters are extremely useful for troubleshooting electrical problems. If you ain’t got no current, then you ain’t got nothing happening. But more than half (53%) of you don’t have one and want to learn more about them. I smell real teaching opportunity here. I’ll see if I can come up with a few cool demonstrations for you.
In the meantime, here’s one of my first videos where I demonstrate how you need to split out the hot and neutral wires in an extension cord if you’re trying to use a clamp meter to measure the load current of an appliance. Watch it HERE.
Tools and Other Devices
Now this is a little more than a casual tool or meter for when you’re connecting to a campground pedestal. But if you’ve ever had to troubleshoot wiring and needed to know what electrical outlet was connected to which circuit breaker, then this is the tool for you.
For less than $50, the Klein ET310 transmitter/receiver pair lets you figure it out quickly. All you need to do is plug the little transmitter end into the outlet in question, then scan the circuit breaker panel with the receiver “wand” and voila – you know which breaker is powering that outlet without resorting to flipping random breakers on and off. Plus the transmitter doubles as a 3-light outlet tester letting you know if there’s a Hot/Neutral polarity reversal, open ground, etc., as well as checking GFCI operation. And yes, the two pieces plug together so one doesn’t get lost in the shuffle. I really like this tool and think that every technician and serious DIY troubleshooter should have one. —Mike
Last Month’s RVtravel.com Posts
These articles are rated Moderate to understand for most RVers.
• RV Electrical Safety: Part 4 – Hot-Skin Voltage. (Mike’s most important article to date.)
• Better 30-amp power connectors.
• Tighten those transfer switch terminals carefully.
• RV Electrical Safety – Part 3 – Measuring outlets.
• Generator grounding and bonding.
These articles are rated Easy to understand for beginners.
Mike’s Featured Tips in last month’s RV Daily Tips Newsletters:
(These are not necessarily electricity related.)
• Don’t forget the fuses.
• Don’t swat at a wasp nest – or at least be prepared if you do.
• What’s better than a carabiner? Well, an S-Biner, of course!
• Cheap engine oil filler funnels.
• Don’t operate without your gloves…
New & interesting finds on Amazon!
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.
Q&A’s from my Facebook group:
I’m getting a lot of interesting questions on my RV Electricity Facebook Group. Here’s one with an answer that’s not obvious. Sometimes the seemingly simple things are the most complicated.
Q: Would it be possible to combine two 15-amp circuits, on separate breakers, to generate a 30-amp input? Would you run into phase problems? —Wilson Ferguson
A: Please don’t. On a 50-amp rig you might have phase problems. On any rig one breaker will trip first grossly overloading the other’s wire and breaker. I’ll also bet it violates code. And someone may shut off one breaker thinking it’s off and get electrocuted as the other is on. —Mike Ehlert
Email me at mike (at) noshockzone.org with your questions.
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
Knowledge is power, and I’m delighted to offer my educational RV Electricity seminars to RV shows and rallies around the country, both large and small. If you know of an RV show or rally that could use this educational content, please contact firstname.lastname@example.org with the subject line Seminars.
Upcoming RVelectricityTM Seminars
Always double-check the times and dates as sometimes these change at the last minute
Enumclaw Expo RV Show near Seattle, WA: Aug. 1-3. See Mike’s topics and the schedule here.
FROG (Forest River Owner’s Group): Goshen, IN: Aug. 14 (3 p.m. to 4:30 p.m.) and Aug. 15 (9 a.m. to 10:30 p.m. and 1:30 p.m. to 3:00 p.m). RVelectricityTM Master-Class Topics – Parts I, II and III (free seminars). Here’s a link to the FROG Rally schedule. Or click on the schedules below to see them in full size.
Hershey RV Show in Hershey, PA: Sept. 11-15, 9 a.m. to 10 a.m. Understanding RV Power & Surge Protection (free seminars).
Holiday Inn Harrisburg/Grantville, PA: Sept. 14, 1 p.m. to 4 p.m./5 p.m. Advanced RV Electrical Troubleshooting. 3-hour class plus 1-hour Q&A ($125 per seat). More information and register HERE.
Camco Store at Amazon.com
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.
By Mike Sokol
Permission to fail
“Never let the fear of striking out keep you from playing the game.” ―Babe Ruth
I was reminded recently of this famous quote from perhaps the most famous home run hitter in the history of baseball, Babe Ruth. You see, my twin boys bought a house last year, and one of their new homeowner projects is finishing the basement into a man-cave.
Of course, I offered to supervise and then assisted by helping them design a complete new electrical system with a 100-amp subpanel, and 8 separate 20-amp branch circuits, each on its own switch. Yes, a lot of power for a basement, but when you start adding up video games the power requirements grow rather quickly.
Let’s play (the game) safe out there…
Mike Sokol is an electrical and professional sound expert with 40+ years in the industry. His excellent book RV Electrical Safety is available at Amazon.com. For more info on Mike’s qualifications as an electrical expert, click here.
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..
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