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Important - check this every time you set up

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Topic: Important - check this every time you set up
Posted By: techntrek
Subject: Important - check this every time you set up
Date Posted: 21 May 2014 at 11:12am
I meant to post this info last year.  Recently it came up in another thread and now I'm finally putting it where it belongs - in its own thread, pinned at the top of the sub-forum where everyone will see it.
 
Out of all the technical assistance I have posted over the years on this forum, out of all the posts made by anyone on this forum, this is the most important one.  It is literally a matter of life and death.
 
You must check for a proper ground connection every time you plug in your pod, and just using a voltmeter or plug-in tester won't detect every wiring fault.
 
I've known since I was a kid why ground connections are important, but as with most people, it wasn't until something affected me personally that I finally paid attention.  Last summer I set our pod up in our backyard so I could clean the roof and the A/C coils (easy access from my raised deck).  I've never needed my 30 amp extension cord to reach the 30 amp outlet in my garage, usually the pod is close enough.  I needed to run the A/C, so this time I did.  I had my kids get in their bathing suits to wash the rest of the pod, water went everywhere, the ground was soaked, and they had some summer fun while they worked.
 
Long after they were done, I had to get into the pod, so I did what all of us have done hundreds of times - I grabbed the door handle while I stood on the wet ground.  I received a noticeable shock, and with my electronics/electric hobby background I immediately knew something wasn't wired right.  Worse, I knew that the entire time my kids were washing our pod they could have been killed.  They were far more conductive than I was; I was wearing rubber-soled shoes and my hand was dry, they were soaked all over, deep into their skin, and were in bare feet.  I don't know how, but only by extreme luck did a nice summer day in the backyard not turn into an awful day at the morgue.  I tracked my problem down to a bent ground pin on my 30 amp extension cord.
 
Hopefully you understand now that a shock isn't something you can ignore.  It is just a lucky warning that a deadly problem exists and you need to get it fixed.  Next time it could be an electrocution.  Slightly different conditions and you are dead.  Saltier water (think beach trip) is more conductive, slightly higher voltage at campground A vs. campground B (amps kill you, but higher voltage makes it more likely), or you get the shock through both arms and not both legs (amps through your heart is what usually kills you).  My shock was across my heart (1 arm and 2 legs) so I was just as lucky that day as my kids.  I'm sure because the measured voltage on that fault was only around 60 volts and not the full 120.  That probably saved all of us.
 
Check out these links, especially the article at the first link, which explains the right way to test for ground issues.  The 2nd link explains how voltmeters, plug- in testers, and intelligent surge protectors can report on some faults - but not all.  I haven't purchased the Non Contact Voltage Tester he describes, which detects if your camper is currently lethal, but it is on my list.  Keep it in your pod and check every time you plug your pod in.

http://www.noshockzone.org/rv-electrical-safety-part-iv-–-hot-skin/ - http://www.noshockzone.org/rv-electrical-safety-part-iv-–-hot-skin/

http://www.noshockzone.org/are-little-shocks-ok/ - http://www.noshockzone.org/are-little-shocks-ok/

http://www.noshockzone.org/category/rv-safety/ - http://www.noshockzone.org/category/rv-safety/


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual



Replies:
Posted By: techntrek
Date Posted: 21 May 2014 at 11:50am

I have now ordered one of the testers.  http://en-us.fluke.com/products/electrical-testers/fluke-1ac-ii-a1-electrical-tester.html?fbid=Aav3CZ6uhLM#techspecs - This is the model you want to order , be careful not to order the "low voltage" (LAC) model.



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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: Seanl
Date Posted: 21 May 2014 at 1:06pm
Thanks for the post Doug. I knew most of this and check it regularly there were a couple of things I did not know. 

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Sean, 2011 Rpod RP-173,2009 Jeep Liberty Rocky Mountain Edition


Posted By: techntrek
Date Posted: 21 May 2014 at 1:39pm
They sell 5-packs of the testers much cheaper than a single (the 5th is basically free), so bulk purchases could be arranged for those attending rallies/roundups/get-togethers in the near future.  I would arrange a bulk purchase for the entire forum, but I think the savings would be wiped out by the cost to re-ship.  Distribution at rallies would solve this problem.
 
If there is enough interest I could look into negotiating a much cheaper price, possibly cheap enough to make the re-ship costs a non-issue.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 21 May 2014 at 6:01pm
Thanks for posting my No~Shock~Zone articles here. And yes, you had a very narrow escape. As you noted in your post, any shock can be dangerous and life threatening. And certainly standing on wet/soggy ground in your bare feet is the worst possible condition.

As far as NCVT (Non Contact Voltage Testers) there are a few alternatives to the Fluke tester shown in my article that are a little less expensive and more available at Home Depot or Lowes. For instance, the Klein NCVT-1 has similar sensitivity to the Fluke VoltAlert and is perhaps $10 cheaper. Klein also makes a dual-range NCVT-2 that will test for really low voltages as well, but it may be a little too complicated for a casual user. So please shoot me a message if you're looking at any other brands before you buy them. I try out all my test gear on a calibrated voltage/distance tester, and not all Voltage testers work exactly the same. I know the Fluke VoltAlert works great, and the Klein NCVT-1 works just as well. And I have a handful of others that also work. But it's best not to go cheap on test gear, especially when lives are at stake.


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mike@noshockzone.org
www.noshockzone.org


Posted By: Keith-N-Dar
Date Posted: 21 May 2014 at 8:43pm
Is this really a problem?  I think it is like the exploding gas pumps caused by cell phones.  I have checked the outlets with my multimeter at all camp sites since I have been camping and never has one wired wrong.  Further one of the most scary articles about this I read said that the "skin on the RV becomes charged and causes electrocution."  It also discussed polarity on an AC circuit.  Fiberglass is non-conductive and AC has no polarity.


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Keith-N-Dar
Boris & Betty (Boston Terriers)
2011 R-Pod 177
2010 Ford F-150


Posted By: techntrek
Date Posted: 21 May 2014 at 9:13pm
Thanks Mike for the update!  I posted this info on another forum and will copy the info on the other tester options.

Keith, I assure you this issue is not BS.  As I posted above, it happened to me.  Mike Sokol has heard from many people who have had the same experience.  The door frame - including the latch assembly - is attached to the pod's frame, and the pod's frame is attached to the ground pin of the electrical hookup (or it is supposed to).  The fiberglass exterior is a non-issue.  AC doesn't have polarity, but one of the two conductors is grounded, as well as the ground itself.  If the frame isn't grounded properly any one of a thousand problems can electrify that frame, and you can die.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 21 May 2014 at 10:36pm
Two years ago in Muncie Indiana, a family had parked their RV in the back yard and plugged their RV into a garage power outlet. They were feeling shocks all week which they "fixed" by wrapping electrical tape around the door handle of the RV. In the middle of the night their 18-year old barefooted son stepped from the wet grass to the metal step of the RV and died from electrocution. The really sad thing is that I was teaching a No~Shock~Zone seminar in Harrisburg, PA just 12-hours before this boy was killed. I still think the easiest test to make sure your RV doesn't have a hot-skin voltage is a basic NCVT such as the Fluke VoltAlert or Klein NCVT-1. The cost is only $20 to $30 and the test takes only seconds. But I have hundreds of RV shock incidents cataloged from readers around the country, so this isn't a rare thing. It might not ever happen to you if you always plug into modern campgrounds. But never trust a garage outlet, and never use a damaged or ungrounded extension cord to power your RV.  

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mike@noshockzone.org
www.noshockzone.org


Posted By: LizKev
Date Posted: 21 May 2014 at 11:43pm
Would your safety chains left on the ground complete the circuit? Would this help at all?

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2014 r-pod 178
2000 GMC Sierra


Posted By: jmsokol
Date Posted: 22 May 2014 at 12:21am
Originally posted by LizKev

Would your safety chains left on the ground complete the circuit? Would this help at all?


No, safety chains would do nothing at all to ground your RV. Nor will putting jacks down on the dirt help stop a hot-skin conditions. There's no substitute for a solid safety ground connection (Equipment Ground Connection or EGC in the National Electric Code) from the frame of your RV through your shore power cord and back to the service panel's G-N-E bonding point.


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mike@noshockzone.org
www.noshockzone.org


Posted By: wingnut2312
Date Posted: 22 May 2014 at 8:08am
Ok, so since the could potentially kill someone, I'm going to ask a very 4th grader ish question. The Non contact pens, are you to stand barefoot or shoed outside with your hand firmly wrapped around the pen? If so, do you touch it to the step or just any solid metal part?
Great info and article, but I wish they would just have a section that says "if you are half retard, do this". I would happily admit to being half retarded and go thetre.

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2014 rpod 182G
Ford Expedition


Posted By: Camper Bob
Date Posted: 22 May 2014 at 8:45am
Wow. That's quite a story. Glad no one was hurt. Thanks for the heads up. Safe Travels.

-------------
Camper Bob and Camper Sue
Gracie the Wonder Dog (12 LB. Mini Dachshund)
2013 Rpod 171HRE(ORPod)
2016 Lance 1685
2015 Nissan Pathfinder


Posted By: jmsokol
Date Posted: 22 May 2014 at 9:24am
Originally posted by wingnut2312

Ok, so since the could potentially kill someone, I'm going to ask a very 4th grader ish question. The Non contact pens, are you to stand barefoot or shoed outside with your hand firmly wrapped around the pen? If so, do you touch it to the step or just any solid metal part?
Great info and article, but I wish they would just have a section that says "if you are half retard, do this". I would happily admit to being half retarded and go thetre.


Actually, here's a video of me doing a hot-skin test with a Fluke VoltAlert.

http://www.youtube.com/watch?v=Y8h64X33aKg - http://www.youtube.com/watch?v=Y8h64X33aKg

Yes, you stand on the ground near your RV after plugging into the pedestal and turning on the circuit breaker, but don't touch the RV with your hand first. You do need to have your hand wrapped around the voltage pen/tester to establish the earth reference but any grip will do. These NCVT pens are all plastic and rated to safely touch up to 1,000 Volts AC without passing any current to the person doing the test, so you don't have to worry about getting shocked if you do touch an energized surface.

All modern RVs have every major metal piece bonded to the chassis, so you can pick anything convenient for this test. The wheels or hitch are great places to test, as are the metal steps and the metal door frame. Note that these testers work from a distance depending on voltage, so if your RV is hot-skin energized to 120-volts it will beep and light up from more than a foot away, sometimes up to 2 feet. If it's energized to 80 volts it will beep from maybe 6 to 8 inches away, and 40 volts will cause it to beep once you touch the surface with the tester plastic tip. There's no need to dig through paint or rust like you would with a voltmeter probe.

Since your tow vehicle is attached to the RV via the metal hitch, it will also have the same hot-skin voltage as your RV. So if your RV is hot-skin electrified and still hooked to your tow vehicle, you can get a shock while opening your car door.

With any voltage tester it's important to establish that the unit itself is working before you do the test. That's why I prefer the style of Non Contact Voltage Tester that requires you turn it on, then has a blinking light showing that the battery isn't dead. Many of the newest testers are "always on" which appears to be convenient. But you won't know if the batteries died while hanging out in your tool box and it could fail to indicate an energized surface. So it's best to poke your tester into the pedestal outlet first to establish that it's still working before you do your hot-skin test.

Please let me know if you have any more questions.


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mike@noshockzone.org
www.noshockzone.org


Posted By: wingnut2312
Date Posted: 22 May 2014 at 9:38am
YES!!! See, that's a proper "half retard" explanation, lol. Thank you!!

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2014 rpod 182G
Ford Expedition


Posted By: Camper Bob
Date Posted: 22 May 2014 at 10:48am
I'm constantly amazed at the level of technical expertise there is on this forum. Keep up the good work. Your advice makes us all safer and makes our Pods more useful and fun. Thank you all who participate here whether asking or answering questions. It makes all of our camping experiences safer and more fun. Safe Travels.

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Camper Bob and Camper Sue
Gracie the Wonder Dog (12 LB. Mini Dachshund)
2013 Rpod 171HRE(ORPod)
2016 Lance 1685
2015 Nissan Pathfinder


Posted By: jan demarinis
Date Posted: 22 May 2014 at 10:56am
I agree! Thank you all.


Posted By: techntrek
Date Posted: 22 May 2014 at 1:46pm
Something I didn't make clear in my first post, if any camper (or an appliance, or the shell of the power pedestal at a campground) tests positive it means 2 things.  Problem one, there is a fault somewhere which has electrified the exterior metal.  Problem two, the ground ("equipment grounding conductor") is not connected properly so it isn't doing its job to prevent problem one from killing you.  So if the tester gives you a positive reading you have 2 problems to fix.  Unplug the camper immediately without touching it, or the power pedestal, only the cord.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: wingnut2312
Date Posted: 22 May 2014 at 1:58pm
So don't touch it with my tongue to see if it sticks or not?

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2014 rpod 182G
Ford Expedition


Posted By: techntrek
Date Posted: 22 May 2014 at 2:00pm
Only try that in very cold weather, after the camper is unplugged.  Wink

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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 22 May 2014 at 7:08pm
Originally posted by techntrek

Something I didn't make clear in my first post, if any camper (or an appliance, or the shell of the power pedestal at a campground) tests positive it means 2 things.  Problem one, there is a fault somewhere which has electrified the exterior metal.  Problem two, the ground ("equipment grounding conductor") is not connected properly so it isn't doing its job to prevent problem one from killing you.  So if the tester gives you a positive reading you have 2 problems to fix.  Unplug the camper immediately without touching it, or the power pedestal, only the cord.


Just a few clarifications. First of all, while you might think there needs to be an internal hot-to-ground fault to produce the voltage in the first place, that's not entirely true. ANY appliance plugged into a power plug can have some current leakage that will produce a voltage of some level. But the AMOUNT of fault current is limited by UL Labs to less than 0.75 mA for an "ungrounded appliance" such as your iPhone charger, or less than 3.5 mA for a "grounded appliance" for something like your microwave oven. Generally, anything plugged into an electrical outlet and NOT malfunctioning will have its chassis migrate to around 1/2 of line voltage. So it's perfectly normal (but somewhat scary) to measure 60 volts AC on the body of your iPhone while plugged into its wall-wart charger. But because the maximum leakage current is supposed to be under 0.75 mA, that's right below the current threshold that most people will notice a shock.

On the other hand, a microwave oven (or any other grounded appliance) can leak up to 3.5 mA of fault current and still be considered "safe" by UL standards. This will generally produce the same 60 volts on the chassis if left ungrounded, but that 3.5 mA of current at 60 volts will produce a very noticeable, but not dangerous shock. And all these leakage currents are additive, so if your RV has a broken ground wire (EGC - Equipment Grounding Conductor) then everything plugged into your RV can leak more current to the chassis, and it's entirely possible to have 20 or 30 mA of leakage fault current available even if nothing is really "wrong". I call this a low-current (high impedance) fault, which can be painful but generally not deadly. Now, if your EGC is in place, then that 20 or 30 mA of current will be drained harmlessly to the grounding point of your service panel. However, if there's no ground path in your power cord and you touch anything metal on your RV while standing on damp ground or grass, then you can feel a very big shock. Now remember that 10 mA is a pretty good shock, and 20 mA will cause your hand to clamp down on a wire or ladder rung and not be able to let go, and 30 mA through your chest cavity for a few seconds almost guarantees heart fibrillation and death in minutes if CPR isn't immediately begun, so even these "low current" leakage voltages can get dangerous.

The second type of ground fault is a high-current (low impedance) short from a hot wire to the chassis inside an appliance or your RV's electrical system. This often happens when a screw is driven through a wire in the wall, or the insulation of a wire has worn through from road vibration, or a cable was pinched in an access door, etc... This type of high-current fault can reach circuit breaker amperage level, making 20 amps (or more) of current available at 120-volts. Without a low-resistance ground connection back to the electrical service panel, touching your RV is equivalent to sticking your finger in the light socket while standing in your bathtub full of water. Since a human body has somewhere around 1,000 ohms resistance with wet hands/feet, that 120-volts will produce upwards of 100 mA of fault current through your body, which is WAY above safe limits. So unless you're pulled off the energized chassis within a few seconds and CPR started within a few minutes, you're dead from electrocution.

Now, this hot-skin test isn't something you need to do every time you walk up to your RV, but I would certainly test every pedestal receptacle ground for improper voltage BEFORE plugging in your RV power cord. Then do a quick check on the chassis/skin of your RV with a NCVT such as a Fluke VoltAlert or Klein NCV-1 to make sure your extension cord ground is good. If there's a voltage on your RV skin/chassis while plugged in, then immediately turn off the pedestal circuit breaker, unplug your shore power connection, and contact the campground manager. After your initial test while making camp, you should only have to pull our your NCVT if you feel ANY kind of shock from your RV while still in camp at the same location. And the same goes for when you visit any of your RVing buddies at their campsites. If you feel ANY tingle at all while touching their RV, then pull out your trusty NCVT and do a hot-skin test for them. If it beeps and lights up, then they have a hot-skin condition of at least 40 volts, which could be a low-current leakage condition (shocks but doesn't kill you) or a high-current leakage condition (deadly under all damp conditions). But for sure they have lost their ground connection and need to power down and unplug immediately. You will NEVER read more than a few volts above earth potential on the skin/chassis of a properly grounded RV. If you do measure more than a few volts, then your ground is broken for some reason.  

Why doesn't your GFCI protect you from these situations. That's another story, but remember there's no GFCI required on a 30-amp TT-30 outlet, it's only required on the 20-amp outlet at the pedestal. 


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mike@noshockzone.org
www.noshockzone.org


Posted By: Tars Tarkas
Date Posted: 22 May 2014 at 7:51pm
An additional fun feature of these testers is that when you have them on while driving under high voltage electric lines -- the kind that run from tower to tower rather than pole to pole -- they will light up and beep.

TT


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2010 176
FJ Cruiser


Posted By: jmsokol
Date Posted: 22 May 2014 at 8:38pm
Originally posted by Tars Tarkas

An additional fun feature of these testers is that when you have them on while driving under high voltage electric lines -- the kind that run from tower to tower rather than pole to pole -- they will light up and beep.

TT


True, and that's because your body or vehicle is actually elevated to several thousand volts above earth potential while standing under power lines. No kidding. In fact, if you park your tow vehicle and RV directly under high-tension power lines (yup, those big ones) you can get a pretty good shock while standing on the ground in bare feet or wet shoes and touching the door handle. I've discussed this phenomenon with a number of Power Company Engineers who say that the current is supposed to be less than 5 mA at the normal 14 ft minimum wire distance to ground suggested by the utilities. However, since that power line could have up to 500,000 volts on it (yup, half-a-million volts), then you could get up to 10,000 volts bias on your vehicle (but at less than 5 mA current). So while the shock could startle you, it shouldn't be dangerous. I'm going to do an experiment this summer showing how a car spark plug attached to the bumper of an RV will spark continuously when connected to a ground rod. Too much fun...

Interesting stuff, eh?


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 22 May 2014 at 10:04pm
Interesting info in your 2nd to last post.  Sounds like that would explain why the voltage between chassis and ground dropped as I turned off each breaker on the converter, and why I never could figure out what was "wrong".  I verified the wiring on the TT-30 outlet and the end of the cord (L5-30) connected to the camper both are right (lower-left to the ground pin is hot), and the ground to chassis looked good.

I've read of high tension line voltages higher than 500,000, both AC and DC.  I think 765k is one popular voltage.  I've seen demos where a fluorescent tube can be lit while standing under them, similar to a Tesla coil.  Amazing the voltage differential can be so great, I never knew you could get an actual shock.  Yes, this stuff is interesting/fun for me.  Cool


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: Cap-n-Cray
Date Posted: 22 May 2014 at 11:30pm
Would a surge suppressor have any effect in this situation?


-------------
Cary
2014 RP-177


Posted By: jmsokol
Date Posted: 23 May 2014 at 12:36am
Originally posted by Cap-n-Cray

Would a surge suppressor have any effect in this situation?

There are basically two types of surge suppressors on the market. One is a surge-only type with MOV devices that will stop voltage spikes from the power line. These cost around $100 but will do nothing to prevent hot-skin shock from an open-ground situation. The second type is a voltage-monitor/suppressor type with a relay that will disconnect your RV from the power line if the ground is open or the voltage goes above or below preset limits. This should protect you from an open-ground condition at the pedestal, but not when Cost is between $200 to $300 for a 30-amp model. See my No~Shock~Zone article at http://www.noshockzone.org/rv-electrical-safety-surge-strips/ - http://www.noshockzone.org/rv-electrical-safety-surge-strips/

However, note that neither of these products will detect or disconnect you from a very dangerous mis-wiring situation I call a Reverse Polarity Bootleg Ground (or RPBG). An RPBG occurs with a DIY guy or old-school electrician added grounded outlets to old (pre-1970's) wiring by adding a jumper between the Neutral and Ground screws rather than running a new grounded wire. If the Hot-Neutral polarity is correct, then this creates a normal Bootleg Ground, which is a code violation but not immediately dangerous. However, if the Hot and Neutral "polarity" is reversed somewhere in the walls or conduit, then the Hot contact is now at 0 volts, while the Neutral and Ground are both at 120-volts. Anything you plug into an RPBG outlet will operate normally, except that the chassis is now at 120-volts with full circuit breaker amperage available. And there is NO tester on the market that will find an RPBG. See my articles at the RV Doctor's website at  http://www.rvdoctor.com/2001/07/friends-of-gary-mike.html - http://www.rvdoctor.com/2001/07/friends-of-gary-mike.html or in EC&M magazine where I bring the RPBG situation to the attention of the electrical contracting industry:
http://ecmweb.com/contractor/failures-outlet-testing-exposed - http://ecmweb.com/contractor/failures-outlet-testing-exposed

Note that a basic Non Contact Voltage Tester will easily find an RPBG mis-wired outlet in seconds, both before and after plugging in your RV power cord.
 
Where do you find RPBG outlets? Certainly not in new campgrounds with proper wiring. But I've heard reports of them in very old campgrounds and boat docks that never ran new wiring when upgrading to grounded outlets. And I've personally seen them in a number of home garages as well as pre 70's church wiring that's been upgraded to grounded outlets by well-meaning or misinformed "electricians", some of whom are actually licensed. So be very careful when parking your RV in your buddy's driveway and plugging into "garage" power. That seems to be where RPBG outlets happen the most.


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 23 May 2014 at 8:18am
Worth repeating in short form, so nobody misses it.  

Even if you have an advanced surge/monitor installed in your camper (or the plug-in version outside), you still need to get a VoltAlert or one of the other models Mike listed previously.

You've spent more than $30 on other camping gadgets, and few of those gadgets can save your life like this one can.

BTW, I've added this topic to the "R-pod manual" thread.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: fwunder
Date Posted: 23 May 2014 at 8:24am
This is a great thread. I ordered my Volt-Alert this morning.

One has to wonder why a Hot-Skin alarm system isn't built in as a standard.

Thank you very much for this information!

fred


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2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: techntrek
Date Posted: 23 May 2014 at 8:41am
Good question.  It wouldn't cost more than the already-required LPG/smoke/CO detectors.  Only catch is it would only work while you had a firm grip on it, while standing on the ground outside.  Two possible solutions - add a large touch pad just above the power connection so you could plug in, press your hand to the pad and get a read-out just above it.  And/or redesign the door handle so it is insulated, and every time you grab it you get a readout above the handle.  There are issues - would it work if the sensor was wet or had road grime on it, what if you are using a plastic step-stool in front of the door, etc.  But there are solutions - put the sensor inside a cover, and maybe only putting it above the power connector is the better location even though it would only get checked once and not every time you get in the camper.

I could see a market for this, but it would take a ton of public education to generate the demand.  Manufacturers wouldn't add it to their campers unless forced by regulations or high market demand.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 23 May 2014 at 10:05am
Actually, there's a pretty easy way to manufacture a built in hot-skin detector (which I've already built and tested). However, it seems like the RVIA and RVDA are not interested in promoting that an RV can become a shock hazard if plugged into a mis-wired outlet or extension cord. Their point of view is that it might scare prospective buyers away from purchasing new RVs. No kidding, I've sat at a desk in front of these guys and asked them about it point-blank. I also had an off-the-record comment from an RV industry official who stated that having an RV's electrical system destroyed by improper voltage hookup was not necessarily a bad thing since now the insurance company would pay to install a new refrigerator, inveter/converter, HVAC, etc... and that RV suppliers would thus be selling more replacement parts. The potential for loss of life from a hot-skin shock wasn't even on their radar.

So yes, while I believe that consumer education about electrical safety is the key to safe RVing, I seriously doubt that the RV industry will fund it unless there's a big push from consumers to do so. That's why I spend so much time developing demonstrations and testing techniques for RV owners. This is not my day job... I'm actually a technology instructor who teaches live music production around the country. I've been pitching the idea of RV consumer and technician electrical safety training for the last several years to the RV Industry, but without any traction. So if you think this is important then please contact your RV manufacturer representative and ask them to support No~Shock~Zone seminars at your rally or RV sales event. I'm already driving around the country teaching my live-sound classes and could also schedule single-day No~Shock~Zone clinics at dozens of RV events every year. But the push has to come from those purchasing new RVs, as that's the only group they'll listen to. You all have my NSZ contact info and links to my articles and videos, so please pass it on to them and tell them you consider this to be an important topic.

Thanks for your interest and support. Keep those questions about electrical safety coming.
    

-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: outermostpod
Date Posted: 23 May 2014 at 10:27am
Just ordered the VoltAlert from Amazon.  Got one for my Father-in-law too.  For $30 bucks it is not worth the risk. Just add it to the checklist of stuff to do when you set up camp.

Thanks for bringing this to our attention. I would have never known.


Posted By: jmsokol
Date Posted: 23 May 2014 at 6:35pm
Originally posted by outermostpod

Just ordered the VoltAlert from Amazon.  Got one for my Father-in-law too.  For $30 bucks it is not worth the risk. Just add it to the checklist of stuff to do when you set up camp.

Thanks for bringing this to our attention. I would have never known.

And thanks to techntrek for posting his story about getting shocked and linking to my No~Shock~Zone site, or I would never have found your forum.


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 23 May 2014 at 8:59pm
Received my VoltAlert this afternoon.  I didn't have time to play with it much (both kids are having a double b-day party + sleepover, we have 18 teens and preteens running around right now... seriously considering sleeping in the pod tonight, lol).  I did test one of my kitchen outlets, which only tested positive on the hot pin.  Tested my 30 amp outlet in the garage, ditto.  Then I plugged in the camper's cord and all 3 pins on the twist-lock tested positive.  I tested the outlet and cord with my voltmeter and it is ok so I assume the pins inside are too close to the tip of the tester (wider openings) causing the false positives.  The frame of my pod tested negatively, yay!

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: Cap-n-Cray
Date Posted: 26 May 2014 at 1:46am
When we bought our Rpod 177 it came with a power cord. I had a new 50 foot 30 AMP boat power cord with twist locks plugs on both ends of the cord. I decided to use the the boat cord and made a cheater adapter to go from the twist plug to a regular 15 AMP plug. I found this plug at Home Depot...



http://www.homedepot.com/p/Pass-Seymour-15-Amp-125-Volt-Straight-Blade-GCM-Plug-PS5266XGCMCCV4/202039721?cm_mmc=shopping-_-googleads-_-pla-_-202039721&skwcid&kwd=&ci_sku=202039721&ci_kw=&ci_gpa=pla&ci_src=17588969

The plug has LED lights that tell you in code if the receptacle your plugging in to is wired correctly. Green LED everything is OK. Red LED or any combination signals a incorrectly wired receptacle. 

I thought it was pretty neat. I may start using them on construction sites


-------------
Cary
2014 RP-177


Posted By: jmsokol
Date Posted: 26 May 2014 at 2:04am
Originally posted by Cap-n-Cray

When we bought our Rpod 177 it came with a power cord. I had a new 50 foot 30 AMP boat power cord with twist locks plugs on both ends of the cord. I decided to use the the boat cord and made a cheater adapter to go from the twist plug to a regular 15 AMP plug. I found this plug at Home Depot...


Very interesting. I'll pick one up next week and see how it can be tricked. There are a number of mis-wiring conditions that standard 3-light testers will not detect, the most dangerous one being an RPBG (Reverse Polarity Bootleg Ground). While this tester will probably find an "open ground" or "reversed H-N polarity", there's no way it can find an RPBG condition. I'll report back once I do some testing. 


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: Cap-n-Cray
Date Posted: 26 May 2014 at 2:17am
On the label: "Bright green LED indicator grounded and properly wired, red LED or red LED + green LED indicator - open ground, reversed polarity, no indicator - open hot, open neutral, hot and ground reversed"

I don't know if it would indicate RPBG.


-------------
Cary
2014 RP-177


Posted By: jmsokol
Date Posted: 26 May 2014 at 2:27am
Originally posted by Cap-n-Cray

On the label: "Bright green LED indicator grounded and properly wired, red LED or red LED + green LED indicator - open ground, reversed polarity, no indicator - open hot, open neutral, hot and ground reversed"

I don't know if it would indicate RPBG.


I'll stake my reputation as an EE that it will NOT find an RPBG. But I test for everything, no matter how sure I am of something. It really looks like a good basic tester for 99% of outlet wiring failures and could be a useful addition to your RV extension cords. We shall see...


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 27 May 2014 at 3:55pm
You guys may have saved a life here! No Kidding!!

My Pod is in the driveway. It's just a hair too far to comfortably plug into garage outlet. I have been using one of my molded Home Depot Yellow Jacket 12/3 25 ft. extension cords for the last few feet inside the garage. It's also the extension cord I take camping. The factory Pod shore power cord goes under the garage door at home.

Soooo, I just got my Fluke VoltAlert from Amazon. Without reading any instructions I pressed the green on button, walked outside and touched the tongue jack. Holy s#%t!! It beeped loud enough to scare the cat! Really! Kinda freaked me out. I touched various other parts of the tongue. Same thing. I tested the steps. Same thing!

I figured it (the tester) must be broken. Time to get out the voltmeter.  I've been using these extension cords for years. I got a 25 footer, 50 footer and 100 footer I use around the property. Never had a problem. I rarely go barefoot. 

With voltmeter, positive probe to tongue jack bolt, negative just stuck in gravel driveway. Holy s&$t again! 39.7 volts. I unplugged the pod!

OK, first thing I checked was garage plug polarity. It is fine. Next, checked continuity in extension cord. It checked fine. Next, I was just able to plug pod shore power cord in garage outlet. No voltage seen at trailer frame. I unplugged and replugged several times just to double check. Next, I put extension cord back in place. Hmmmm. No hot-skin.

Sooo, I started playing with the pod shore power cord/extension cord interface. I could actually hear a faint "crackle". Obviously, a good connection is not being made between adapter and extension cord. I would guess it's the ground connection. I have had those break off before.

Until I am comfortable that I have solved the problem, I will not use the extension cord and will keep my VoltAlert very close by!!

Thanks again!!

fred




-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: techntrek
Date Posted: 27 May 2014 at 7:08pm
Originally posted by fwunder

You guys may have saved a life here! No Kidding!!


Wow, already!  I expected to eventually hear back that somebody tested positive, but not in the first 1-2 weeks.  Glad to hear the tester caught that.

Everyone else, if you are still sitting on the fence about ordering ordering one of those testers, do you need any more proof?

Mike, any thoughts on my positive test on all 3 pins of my power cord?  Maybe water intrusion?


-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 27 May 2014 at 7:26pm
Originally posted by techntrek


Sny thoughts on my positive test on all 3 pins of my power cord?  Maybe water intrusion?

There's nothing wrong with your Twist-lock connector. It's beeping everywhere because of the large contact areas inside the plug. These capacitive testers are calibrated to find 120-volts on a small surface are such as an extension cord or 15-amp Edison outlet. Of course something as large as an RV hot-skin will cause them to light up at as little as 40-volts and a foot or two away. Sure gets your attention, doesn't it?

That ability to beep at as low as 40-volt and from a foot away with a 120-volt hot-skin is what I discovered in my initial tests. None of the NCVT manufacturers were aware that their testers would work like that and would be useful for finding RV hot-skin voltage. I have dozens of emails from RV owners around the world who say that I probably saved a life. Please contact your RV dealer and manufacturer about supporting more No-Shock-Zone articles and clinics. R-pod and Forest River should know about this test procedure.

-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: Kermit
Date Posted: 27 May 2014 at 9:41pm
When checking the voltage of a possible hot skin, what's the proper way to test if you don't have a good earth ground near by or your multimeter cords aren't long enough?

-------------
'14 182g
Towed by various Jeeps


Posted By: jmsokol
Date Posted: 27 May 2014 at 10:17pm
Originally posted by Kermit

When checking the voltage of a possible hot skin, what's the proper way to test if you don't have a good earth ground near by or your multimeter cords aren't long enough?

A NCVT such as a Fluke VoltAlert gets its ground reference by coupling through your feet to the ground, which is why you need to grip the tester in your hand. For a voltmeter test, a screwdriver in the ground will suffice for earth reference. If you're in dry soil, dump a gallon of water on the dirt first to improve conductivity. Please note that this is NOT a true ground rod and won't protect you from a hot-skin current leakage. It's a high-impedance earth reference at best, but should give you an accurate earth potential measurement using a modern digital voltmeter. Don't use a solenoid tester for this measurement as it has too low of an impedance for this type of quickie earth ground. 


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: Kermit
Date Posted: 28 May 2014 at 12:05am
Ok, thanks.

I have a no touch cheap tester that seems to work well for testing the power outlets. I thought i had a hot skin condition this past weekend on our trip. The 30 amp outlet at the power post had proper polarity however I was getting a positive test with my no touch tester around the steps,door frame, and frame behind the steps. I had to touch the tip of the tester to the surfaces for it go off though.(My power distribution panel for the rv is directly next to the door just inside within 8 inches.). I switched over to the 20 amp outlet on the post and at first my tester was positive at the steps but neg on the door frame. I double checked the polarity of the 20 amp outlet and it was correct. Afterwards I could not get a positive signal again at the steps or anywhere else.  (I know my tester was working bc I check the breakers in my distribution panel and it worked). I never switched back to the 30 amp outlet and tested the camper again hooked to 30 amps.  


At home in the driveway I have a 30 amp outlet and I do not get a positive result.   I have not checked with my multimeter yet as I wasn't quit sure how to reach a ground for my meter. 


-------------
'14 182g
Towed by various Jeeps


Posted By: jmsokol
Date Posted: 28 May 2014 at 4:26am
Originally posted by Kermit

I have a no touch cheap tester that seems to work well for testing the power outlets. I thought i had a hot skin condition this past weekend on our trip. The 30 amp outlet at the power post had proper polarity however I was getting a positive test with my no touch tester around the steps,door frame, and frame behind the steps.

Everyone should be aware that reversed Hot-Neutral polarity by itself WILL NOT cause a hot skin condition of any kind. It will, however, endanger the life of any technician working inside an open electrical panel that's powered up.

Also, it's important that your NCVT is calibrated against some known standard. Some of them have higher sensitivity than others and thus there's no easy way to predict the actual voltage they'll trigger on with various energized surface areas. Even with a common NCVT, there will be a lot of trigger voltage variance depending on how large of a surface area is energized. If you get ANY NCVT beep/flash touching the tester tip to ANY part of your RV, then I would suspect you have at least 40-volts hot-skin. Usually, beeping at 4 inches away from an RV chassis suggests around 60 volts, 8 inches away suggests 80 volts, and 1 to 2 feet away suggests 120-volts. Of course, an RV with a totally metal skin will offer a much larger energized surface than a fiberglass RV. So an Airstream with an aluminum body at 120-volt hot-skin will light up a tester from 2 feet away, but your R-pod with 120-volts might only do it from 1 ft away. 

However, the only way to know for sure is to do exactly what you propose... measure between earth ground and the RV chassis with an actual voltmeter. Remember that you'll need to poke through any paint or rust on the RV to get an accurate reading, so I've found that the lug-nuts on the wheels to be a good spot to poke a meter probe that won't damage any cosmetics. No need to try this at multiple spots on your RV. If it tests high at one spot, then it will be everywhere. Measuring any more than 2 or 3 volts from the RV chassis to an earth ground rod reference is suspicious and needs to be looked at much closer.

As an example, here's a video of me testing a 40-ft RV for various hot-skin voltages using a Fluke VoltAlert.  http://www.youtube.com/watch?v=Y8h64X33aKg - http://www.youtube.com/watch?v=Y8h64X33aKg Kids, don't try this at home as it's a VERY dangerous experiment to do. However, I do perform this demonstration in my NO~Shock~Zone clinics using various RVs at hand. It's a real crowd pleaser...

 


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 28 May 2014 at 8:32am
Kermit, one possible ground connection, if you are testing with a voltmeter, would be an extension cord plugged into the 20 amp outlet.  Just make sure you are hitting the ground pin and not the hot leg or you could get a false positive.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: fwunder
Date Posted: 28 May 2014 at 1:29pm
This was definitely a wake up, slap in the face revelation for me after finding I had a hot skin situation in my driveway just because I was trying to save a few dollars with my extension cord. Really pretty stupid considering I just ordered a 25 foot proper extension for $36.00.

http://www.amazon.com/gp/product/B000IPAK9S/ - http://www.amazon.com/gp/product/B000IPAK9S/

Next will be a proper 30 amp receptacle for home.

fred


-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: Kermit
Date Posted: 28 May 2014 at 2:52pm
At the site I was at this past weekend, if both the 30 amp outlet and the 20 amp had proper polarity, would the possible hot skin reading I was getting caused by a faulty ground on the power post.  What is the correct procedure to verify the ground on the outlets?

I will be using this same camping spot in the future as my in laws have a permanent site there and the site I used is the only tent site that they allow small campers/pop ups to use. 

Thanks

Joe


-------------
'14 182g
Towed by various Jeeps


Posted By: techntrek
Date Posted: 28 May 2014 at 3:06pm
Assuming the outlets are wired correctly, then a broken ground is likely the only problem.  This is the situation I encountered at home last summer.  The best way to test for this is with a voltmeter - testing for continuity between a known good ground connection (another outlet or the enclosure) and the ground in question.  Or testing for continuity with the neutral.  Or, testing for voltage between the hot leg and the ground pin.  A plug-in tester would also identify a broken ground, probably doing the same thing as the last test I mentioned.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 29 May 2014 at 7:38am
Originally posted by techntrek

Assuming the outlets are wired correctly, then a broken ground is likely the only problem.  This is the situation I encountered at home last summer.  The best way to test for this is with a voltmeter - testing for continuity between a known good ground connection (another outlet or the enclosure) and the ground in question.  Or testing for continuity with the neutral.  Or, testing for voltage between the hot leg and the ground pin.  A plug-in tester would also identify a broken ground, probably doing the same thing as the last test I mentioned.

One thing I do as a quickie alert is to leave a basic 3-light cube tester plugged into an RV outlet that's visible. If you do have a ground open up on an extension cord, you'll see the light pattern change. It's not a definitive test for every problem, but it will tell you if there's a lost ground.

And yes, using the ground of a second extension cord to test for hot-skin voltage is valid, but only if it's correctly wired with solid continuity.

Also, while a surge protector won't alert or protect you from an open ground or hot-skin condition, a surge/voltage protector from a company like Progressive Industries will disconnect your RV from the hot/neutral lines if it detects an incoming open ground. That should protect you from 99% of outlet failures, but WILL NOT detect or protect you from an RPBG hot-ground. I think the $300 cost of a voltage/surge protector is pretty cheap insurance considering the investment you have in your RV.



-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 29 May 2014 at 8:30am
Mike,

I've been doing quite a bit of reading since my chassis lit up from an open ground extension cord. My understanding now is that the open ground itself could not be causing the hot-skin. There must be a circuit leak somewhere else causing current to the chassis. Is this correct? If so, how would I check the rPod appliances and circuitry to expose the leak?

Thanks for the info!

fred

Edited to add: My garage is the only part of my home that was not rebuilt a few years ago and has miles of wiring and it's own panel. Could there be a "short" upstream of the pod causing a leak?



-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: Old Dingo&Mrs.Dingo
Date Posted: 29 May 2014 at 9:09am
I've been following this thread with great interest, and I will be the first to admit, I know very little about electricity, except the more I learn about it, the less I seem to know.  
If we keep the safety chains and tongue jack on the ground, without an insulating wheel or plate, how can the "hot skin" be a danger?  (assuming the chains and jack are resting directly on the earth or grass, and not on a concrete pad)   The human body isn't as good a conductor as the steel jack or the safety chains.  Electricity chooses the most direct (easiest) path to ground, and we are using the same "ground" in both cases.  What about a external ground strap from the chassis to a conductive "pin" in the ground, installed before the unit is connected to the "power supply"?   Maybe a plastic mat in front of the step?  (I use one anyway to limit the dirt tracked into the 'pod)  Shouldn't we be advocating these steps, as well as testing, as part of a safe "power post connection procedure", knowing that everything can change the minute someone backs into a power post?? 


-------------
Old Dingo and/or Mrs. Dingo
181G
2013 Jeep Grand Cherokee


Posted By: jmsokol
Date Posted: 29 May 2014 at 10:06am
Originally posted by Old Dingo&Mrs.Dingo

I've been following this thread with great interest, and I will be the first to admit, I know very little about electricity, except the more I learn about it, the less I seem to know.  
If we keep the safety chains and tongue jack on the ground, without an insulating wheel or plate, how can the "hot skin" be a danger?  (assuming the chains and jack are resting directly on the earth or grass, and not on a concrete pad)   The human body isn't as good a conductor as the steel jack or the safety chains.  Electricity chooses the most direct (easiest) path to ground, and we are using the same "ground" in both cases.  What about a external ground strap from the chassis to a conductive "pin" in the ground, installed before the unit is connected to the "power supply"?   Maybe a plastic mat in front of the step?  (I use one anyway to limit the dirt tracked into the 'pod)  Shouldn't we be advocating these steps, as well as testing, as part of a safe "power post connection procedure", knowing that everything can change the minute someone backs into a power post?? 


All not true. Jacks and chains on the ground do not "ground" your RV. In fact, the earth itself is a pretty poor "ground". That is, even a ground rod driven 8 ft into the soil can have a resistance of up to 100 ohms and still be code compliant. The actual "ground" wire in your extension cord is technically called an EGC (Electrical Grounding Conductor" which must be connected by a low-impedance path (less than 1 ohm) back to the service panel's Ground-Neutral-Earth bonding point. This creates a local "ground plane" which is what gets rid of any leakage currents in your RV's electrical system which is what causes hot-skin voltage.

The idea that electricity only follows the path of least resistance is an old wives tale. Actually, it follows ALL paths at the same time. Remember that the human body with wet hands is around 1,000 ohms resistance. The jacks sitting on dry dirt might only be 1,000 to 5, 000 ohms resistance, maybe higher. If you have an open ground and any amount of current leakage (everything leaks) your RV can easily have 40 to 120-volts on its chassis and skin. If that's the case, then touching the door handle or steps while standing on the ground will allow current to flow through your body. How much current is dependent on both the voltage of the RV's chassis and skin plus the available current from the leakage. It could be a high-impedance (low current) leakage, in which case it will be self limiting to maybe 10 mA or so. That will give you a shock but not be lethal. However, if the current ability increases, then your body will draw as much current as your impedance to ground will allow. Since voltage divided by resistance equals current (E/R=I) even 40 volts across your 1,000 ohms of wet-skin body resistance could allow 40 mA (milliamperes) of current to flow through you. And if you've got 120-volts on your RV's chassis/skin from a hard short, then you can receive 100 mA of current through your body. Only 20 mA is needed to cause your hands to grab on an not let go of an energized conductor. And 30 mA for a few seconds is almost guaranteed to cause your heart to go into fibrillation which causes death in minutes without immediate CPR.

So the only thing protecting you from this is your EGC (Electrical Grounding Conductor) ground pin on your extension cord, which must be connected back to your service panel's Ground-Bonding point. Anything else won't work and offers a false sense of security. Don't think that putting a rubber mat on the steps or wrapping the door handle with electrical tape will protect you. Remember that anything attached to a hot-skin RV is also electrified, including your tow vehicle.

See why I want to do more clinics on RV grounding? This is stuff that even RV Technicians fail to understand. And certainly, most consumers who own RVs are not aware of shock dangers. If you ever feel the slightest tingle while touching your steps or door handle, then turn off the pedestal breakers and unplug immediately. There's something really wrong which could kill the next person who touches your RV. Never let an electrician or technician convince you that a "small shock" is OK because it's not. See  http://www.noshockzone.org/are-little-shocks-ok/ - http://www.noshockzone.org/are-little-shocks-ok/ for my article on the subject.


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 29 May 2014 at 1:18pm
OK, please help me understand what is happening here.

I did a bit of an experiment this morning. Using a landscape nail about a foot deep in driveway I connected multimeter to it and to stair bolt. I then purposely plugged in with an open ground and all breakers on. I then carefully started turning off breakers, top to bottom and recorded voltage.

Closed Ground - all breakers on => 0.132v

Open Ground - all breakers on => 41.1v

Open Ground - #2 AC breaker off => 40.1v

Open Ground - #2 AC and #3 Reefer breakers off => 39.9v

Open Ground - #2 AC, #3 Reefer and #4 Micro breakers off => 28.0v

Open Ground - #2 AC, #3 Reefer, #4 Micro and #5 WH breakers off => 27.3v

Open Ground - #2 AC, #3 Reefer, #4 Micro, #5 WH and #6 GFCI breakers off => 23.1v**

**Only breaker on is Converter.




Only Converter:



Now, I'm more confused than ever. Is my converter leaking a dangerous amount voltage? Is there a threshold of allowed voltage leak? What's going on?

Thanks for helping me try to understand this.

fred






-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: jmsokol
Date Posted: 29 May 2014 at 2:02pm
This is normal leakage currents that occur in ALL appliances and gear plugged into 120-volt AC. Here's what's happening. For a piece of electrical gear to be sold in the US it has to pass UL Ratings. UL allows up to 0.75 mA of hot-to-chassis fault current leakage from an "ungrounded" appliance like your iPhone charger, and up to 3.5 mA of hot-to-chassis fault current from a "grounded" appliance like a microwave oven or charger/inverter. Generally there's as much leakage from hot-to-chassis as there is neutral-to-chassis, so you end up with around 60 volts on ANY chassis that's not tied to the ENG (ground wire).

These normal fault currents are additive, so the more circuit breakers you turn on, the more leakage currents will show up on your RV chassis (and skin). So a single appliance (such as a microwave) could be leaking 2 mA to its chassis, but turn on 10 of them and you'll get 20 mA of total leakage current. This is what I call a high-impedance current source since it has the potential of supplying on a small amount of fault current to your body. The reason why the measured voltage is low with only one breaker on and gets higher the more breakers you turn on is that your meter and grounding nail is sinking some of the current to "earth" which forms a voltage divider. So that shows that you have no significant leakage current sources in your RV. If you did, the measured voltage to ground would be 120-volts when you hit the breaker connected to the wire that's shorted to the frame, etc....

So here's the thing. There's a high likelihood that even if you had a disconnected EGC (ground) on this particular RV right now, that there would be insufficient fault current available to cause a lethal shock. But that's just at this very moment. At any time one of your appliances could develop just a little more leakage current to its chassis which ends up on your RV chassis and could kill you or a loved one the next time you touch the ground and RV at the same time. The job of the power cord's safety ground (EGC) is to drain these potentially dangerous currents to the G-N-E bonding point in the service panel and prevent ANY voltage from occurring on the chassis (and skin) of your RV.       

Believe it or not, the job of the ground rod (GEC or Grounding Earth Conductor) is not to trip your circuit breaker in the event of a short circuit. The ground rod is primarily there to absorb the energy of near lightning strikes. That's why just poking a ground rod in the earth doesn't actually "ground" your RV. It needs the low impedance EGC ground wire path back to the panel to create a true safety ground.


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 29 May 2014 at 2:17pm
Thanks Mike! Now I feel a little better.

So, if my VoltAlert alerts me it's time to figure out what's going on and best to unplug until I do!

Thanks again!

fred


-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: techntrek
Date Posted: 29 May 2014 at 2:47pm
Fred, what you describe is what I found with my pod last year.  Mine started off with about 60 volts with all breakers on, and that voltage decreased as each breaker turned off.  At the time it drove me nuts trying to figure out what my "fault" was, I expected the voltage to go away when I turned off breaker X, therefore the appliance(s) on breaker X were the problem.  Having it go down with each breaker was very confusing.
 
At least you only need to track down a disconnected ground somewhere, probably a bent ground pin.


-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 29 May 2014 at 2:58pm
Originally posted by fwunder

Thanks Mike! Now I feel a little better.

So, if my VoltAlert alerts me it's time to figure out what's going on and best to unplug until I do!

Thanks again!

fred

Exactly right. As you can see, it only takes a few seconds to do a hot-skin test with a Non Contact Voltage Tester like a Fluke VoltAlert or Klein NCVT-1. I would do a hot-skin test every time you plug into a new power source, and anytime you feel the slightest tingle. If your tester is beeping near the metal of your RV, then unplug from shore power immediately and figure out what's really wrong. At the very least you have a broken EGC ground connection in a power cord or pedestal outlet, and potentially something much worse.



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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 29 May 2014 at 3:05pm
Let's have a big THANK-YOU to techntrek for bringing this problem to the attention of the forum. Thumbs Up

Now all of you need to spread this important safety info to any other RVing groups you belong to.



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mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 29 May 2014 at 3:38pm
Well, I sure learned a lot and will happily spread the word. Actually, I've learned a lot from this and many of the threads here.

Doug, I owe you a dozen crabs and some cold Natty Premium! Hug


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2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: techntrek
Date Posted: 29 May 2014 at 10:07pm
Love dem crabs, hon!

(thick Baltimore accent, for those that don't know)


-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 31 May 2014 at 11:51am
Originally posted by techntrek

Love dem crabs, hon!

(thick Baltimore accent, for those that don't know)

Make sure they're Maryland Crabs, not those things from Texas or the west coast.

FYI: I'm making a pitch to FROG (Forest River Owners Group) about letting me do some No~Shock~Zone clinics at their conventions, perhaps even one of your R-Pod rallies. I have a bunch of table-top and RV-sized demonstrations about electricity and electrical safety I can bring to the party.
 


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: fwunder
Date Posted: 31 May 2014 at 3:30pm
Originally posted by jmsokol


Make sure they're Maryland Crabs, not those things from Texas or the west coast.
 

There is a different crab than a Maryland Blue Crab?! Can't be! LOL

And, there are thousands of different kinds of seasonings and then there is http://www.oldbay.com/ - Old Bay . It's an easy choice.

BTW, I am sure your demonstrations are eye openers for a lot of folks.

fred


-------------
2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits
2008 4Runner Limited 4.0-liter V6
Yes, those are wild ponies dining on grass while dumping tanks!


Posted By: jmsokol
Date Posted: 31 May 2014 at 7:30pm
Originally posted by fwunder


And, there are thousands of different kinds of seasonings and then there is http://www.oldbay.com/ - Old Bay . It's an easy choice.

I drive about 50,000 miles a year teaching my sound mixing classes, so I get to eat out all over the country. However because I grew up in Maryland, I've given up eating crabs or shrimp anywhere in the country except the east coast. I hate being disappointed since there's simply nothing like Old Bay for crabs and shrimp.

Now every area of the country has it's own food specialties, so I love real New York Pizza in NYC, and Lobster in Maine is fabulous, Salmon in Seattle is the best, and brisket in Texas is out of this world. So don't think I'm dissing your area of the country, because I've been there and loved your food. But I've learned not to buck the system, so crabs in Indiana are a big mistake and a hamburger in a Chinese restaurant is just wrong. That's why I always ask the locals about the type of food they eat at home, then that's what I look for in a local restaurant.

FYI: My twin brother is flying back from California to Maryland for our birthday party in June, and guess what he asked for on the b-day menu? That's right, a bushel of blue crabs plus shrimp steamed in beer and Old Bay. Yummm.  Thumbs Up




-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 31 May 2014 at 10:48pm
Hopefully your schedule will coincide with a few of the upcoming R-pod and FR get-togethers, if those that are organizing them are interested.

I need a bushel of crabs now.  Our personal rule - always order the biggest ones they have.  I'd rather have a half-dozen extra-larges than 2 dozen mediums.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 01 Jun 2014 at 3:36pm
Originally posted by techntrek

Hopefully your schedule will coincide with a few of the upcoming R-pod and FR get-togethers, if those that are organizing them are interested.


Are there any East Coast R-pod or FR events I should be aware of? Remember, I'm located in western Maryland.


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 01 Jun 2014 at 9:29pm
None that I know of in the near future.  We have an Events section, I just looked through it and the only ones close are one in KY, and a potential one in the northeast if plans are firmed up.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: TR_Alaska
Date Posted: 06 Jun 2014 at 6:43pm
Wow, many thanks, especially to techntrek and jmsokol. (And I have read jmsokol's articles on the other site, too) I just received my NCVT (the one techntrek just got), so I feel much safer. I also got the voltage tester that fwunder got. I am also insisting that my wife read and understand this stuff, too. We are both new to RVing.  THANK YOU!


-------------
2015 RP178 - 2000 Toyota Tundra


Posted By: jmsokol
Date Posted: 06 Jun 2014 at 8:53pm
Originally posted by TR_Alaska

Wow, many thanks, especially to techntrek and jmsokol. (And I have read jmsokol's articles on the other site, too) I just received my NCVT (the one techntrek just got), so I feel much safer. I also got the voltage tester that fwunder got. I am also insisting that my wife read and understand this stuff, too. We are both new to RVing.  THANK YOU!

You're most welcome. Glad we could help.




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mike@noshockzone.org
www.noshockzone.org


Posted By: betsypgarmy@yahoo.co
Date Posted: 09 Jun 2014 at 11:55pm
Looked at the You Tube Video. Excellent. The speaker mentioned you may have an RV (RPod) that is not properly maintained. Explain?

Thank you!

The Conways
RPod 177
2012
2012 Toyota Highlander


-------------
Betsy and Jim Conway
Two Scotties
2012 Highlander
2012 R177


Posted By: jmsokol
Date Posted: 10 Jun 2014 at 12:16am
Extension cords with cuts or pulled out wires are a big cause of hot-skin voltage. As are cheap, molded dog-bone adapters. The RVs themselves can also have problems internally as I've seen the twist-lock shore power connector lose the ground lug inside which I assume was from too much lateral force on the plug while attached. Also I think it's a good idea that you check the tightness of the screw connections inside your circuit breaker panel every season, especially if you've traveled a lot of miles which tends to make screws vibrate loose. That should probably be part of your spring de-mothballing. However, this screw tightening isn't a factory recommendation, it's my own theory based on decades of trying to keep sound gear running that's been hauled around in a truck. I'm working on some of these recommendations with Gary Bunzer (the RV Doctor) and we'll be ready to make some official recommendations on this subject later.


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 10 Jun 2014 at 6:53am
The twist-lock on my pod went bad last year - not the ground though, it was either the hot or neutral.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 10 Jun 2014 at 7:11am
I'm also working on a ground-leakage test as well as a EGC (safety ground) impedance test I feel that RV technicians should know how to perform. This could become part of a yearly RV electrical safety check.


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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 12 Jun 2014 at 7:50pm
Please post the following to any forums you belong to.

Mike Sokol from The No~Shock~Zone will appear live on the RVtravel webinar on Saturday, June 21 at noon EST. He'll be discussing RV electrical safety as well as announcing his upcoming eBook on Amazon titled "No~Shock~Zone - RV Electrical Safety". Here’s the link to the webinar: https://www.youtube.com/user/RVtravel - https://www.youtube.com/user/RVtravel

Email your RV electrical questions in advance to mike@noshockzone.org

Thanks... Mike Sokol (jmsokol)


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 12 Jun 2014 at 9:51pm
Thanks for the update.

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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 13 Jun 2014 at 7:19am
If you think this announcement should be moved to a new thread, please go ahead and do so. Thanks for your support with this.


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mike@noshockzone.org
www.noshockzone.org


Posted By: Tars Tarkas
Date Posted: 13 Jun 2014 at 8:10am
Originally posted by jmsokol

The RVs themselves can also have problems internally as I've seen the twist-lock shore power connector lose the ground lug inside which I assume was from too much lateral force on the plug while attached.


I installed a whole-pod surge protector a few weeks ago.  I installed just inside the twist-lock connector.  It wasn't theoretically necessary, but as a practical matter I removed the twist-lock out in the process.  I was extremely disappointed to find that two of the wires (I forget which) were not torqued down at all. The wires could be removed from the connections without the use of a screw driver.  The potential problems that could have caused are sobering to think about.

It isn't easy getting in there and dealing with three 10 gauge wires in tight quarters isn't fun, but your advise is well founded based on my experience.  Just add that it's a good idea to check all of the wire connections you can find and tighten them down very firmly.

TT


-------------
2010 176
FJ Cruiser


Posted By: techntrek
Date Posted: 13 Jun 2014 at 11:25am
Originally posted by jmsokol

If you think this announcement should be moved to a new thread, please go ahead and do so. Thanks for your support with this.

Nope, all good.  Definitely related to this thread and probably will get more exposure here.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 13 Jun 2014 at 11:37am
Originally posted by Tars Tarkas


I installed a whole-pod surge protector a few weeks ago.  I installed just inside the twist-lock connector.  It wasn't theoretically necessary, but as a practical matter I removed the twist-lock out in the process.  I was extremely disappointed to find that two of the wires (I forget which) were not torqued down at all. The wires could be removed from the connections without the use of a screw driver.  The potential problems that could have caused are sobering to think about.

Not only do the factories occasionally forget to tighten down the screws, but road vibrations will also cause them to loosen up. In the pro-sound biz the recommendation is to check screw torque on the electrical distro boxes at least once a year. If this is a new RV, I would bring it to the attention of the dealer and manufacturer. That's the only way they'll learn.




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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 17 Jun 2014 at 7:51pm
My first eBook - No~Shock~Zone RV Electrical Safety is now online at http://www.amazon.com/dp/B00L2DWBD8 - http://www.amazon.com/dp/B00L2DWBD8

Mike Sokol


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mike@noshockzone.org
www.noshockzone.org


Posted By: Budward
Date Posted: 20 Jun 2014 at 4:11pm
HOLY CRAP!

I just had an incident when adding an outlet for the inverter near the TV connections.
Breakers off- confirmed existing outlet was dead by the absence of the indicator light on the power strip I checked with.
Popped back off outlet and pulled the two romex cables off.  (Boy I really dislike those el cheapo stab outlets FR uses, no screws to fasten wires)   I was changing out the outlet to a conventional design, ie not the square face plate hole, so I could add a second duplex outlet next to it, of a different color, for inverter power.  Common face plate, one white outlet pair and one grey outlet pair.
Something touched and FLASH/POP
What the HECK?
Note NO breaker tripped as they were already off!

Grabbed my handy Fluke detector and found it lit up on the white wire of one of the romex cables!

Long story short-   found an L5-30R connector, that I used to make a shortened power cord, made by Well Shin and bought off Amazon- had the incorrect color code screws in the connector.!!!
The silver screw, which is supposed to be neutral, and brass screw, which is supposed to be hot were reversed!
These screws are captive and CANNOT be switched in the field.
Again HOLY CRAP-   this could have killed someone!  Because this was the main power feed to the camper it had the entire camper's hot and neutral reversed.
I'm still a little upset and wonder where I should take this-   this kind of error by a manufacturer could get someone killed!



-------------
2014 179
Towed by a 2015 Ford Transit Diesel
Supervised by a German/Aussie mix and a Labradoodle!


Posted By: techntrek
Date Posted: 20 Jun 2014 at 4:40pm
Happily the popping sound wasn't you.  Since the part came from China I'd contact them through Amazon.  Issues I've had have always been resolved, although none have been a manufacturing defect...

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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: Budward
Date Posted: 20 Jun 2014 at 5:18pm
Yeah the connector actually looked to be really high quality for about half the price of others.   Never dreamed they'd reverse the screws...
The cord was actually one I made up for the generator and wouldn't normally be used plugged into AC power since it is only about 8 ft long..but I had done so at the house rather than leave the big cord out to weather, get chewed by rodents etc..




-------------
2014 179
Towed by a 2015 Ford Transit Diesel
Supervised by a German/Aussie mix and a Labradoodle!


Posted By: jmsokol
Date Posted: 20 Jun 2014 at 5:48pm
I don't trust ANY imported electrical products until I test them myself. We see this problem of swapped wires all the time with imported microphone and speaker cables. There's really nothing you can do to get the message back to China, which is a shame. That's one really good reason to pay a little more and buy American made products (when you can).   

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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 20 Jun 2014 at 7:54pm
Originally posted by Budward

HOLY CRAP!

Grabbed my handy Fluke detector and found it lit up on the white wire of one of the romex cables!

Reversed polarity (swapped hot and neutral) is really dangerous when you're working on wiring and assume the neutral isn't hot. NCVT testers like the Fluke VoltAlert are great for finding this sort of swapped-hot connection.


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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 21 Jun 2014 at 10:13pm
Thanks to everyone who watched my webinar guest appearance today on http://www.youtube.com/rvtravel - RVtravel - YouTube . They've asked me to come back for another show in a few weeks, so send your RV electrical questions to mailto:mike@noshockzone.org - mike@noshockzone.org and I'll put them on the list.

Mike Sokol
mailto:mike@noshockzone.org - mike@noshockzone.org
http://www.NoShockZone.org - No Shock Zone

-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 23 Jun 2014 at 7:11am
Sorry I had to miss this round.  Saturday mid-day was my only "free" time all weekend to get some chores done around the house.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 23 Jun 2014 at 7:23am
You can see the rerun at http://www.RVtravel.com - www.RVtravel.com where they'll break it up into single topics. Also note that they're changing the webcast time to Sunday evenings at 6PM west coast, 9 PM east coast time. Too many people want to get chores done or play golf Saturday mornings. Go figure... LOL

They've also asked me to do a weekly "Ask the Expert" video series. So if any of you have questions you would like me to answer in a video, please email them to me at mike@noshockzone.org.


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 28 Jun 2014 at 1:35pm
In addition to No~Shock~Zone RV Electrical Safety, I"m now doing a series of video shorts on RVtravel called Ask The Expert. My first two videos are about RV safety during lightning storms.

Videos: http://www.youtube.com/watch?v=abLUcHZx6OU&list=UUARpsGWj6MJ7JE78OcfWKWw - http://www.youtube.com/watch?v=abLUcHZx6OU&list=UUARpsGWj6MJ7JE78OcfWKWw

http://www.youtube.com/watch?v=ZBv7TCkea4A&list=PLq052IybXEqV3yyIF8yfV3Mfr7TQMcz5b&index=2 - http://www.youtube.com/watch?v=ZBv7TCkea4A&list=PLq052IybXEqV3yyIF8yfV3Mfr7TQMcz5b&index=2

And here's an outside review of the eBook: http://www.loveyourrv.com/noshockzone-rv-electrical-safety-ebook-review/%20 - http://www.loveyourrv.com/noshockzone-rv-electrical-safety-ebook-review/

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mike@noshockzone.org
www.noshockzone.org


Posted By: jmsokol
Date Posted: 29 Jun 2014 at 7:52pm
techntrek, I've been trying to send you a PM, but your inbox is full. Let me know if you would like a full review copy of my No~Shock~Zone RV Electrical Safety eBook. http://www.amazon.com/dp/B00L2DWBD8


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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 29 Jun 2014 at 10:06pm
Whoops, I've now cleared out some room.  Sending an email to you.

-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 03 Jul 2014 at 10:56pm
Sadly, a 3-year-old boy was electrocuted on Monday when the touched the electrified skin of his family RV in the back yard. Here's the video interview I just did about this for RVtravel. http://www.youtube.com/watch?v=opuult8jMOo&feature=youtu.be%20 - http://www.youtube.com/watch?v=opuult8jMOo&feature=youtu.be

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mike@noshockzone.org
www.noshockzone.org


Posted By: Bulldogpod
Date Posted: 07 Jul 2014 at 10:52am
jmsokol, that was you in the video? What a great segment. I subscribed after watching it on youtube. Thanks techntrek for posting, I ordered the Fluke 1AC today that you recommended. I am still a little shy about testing it on the outlet itself, even though I know it is plastic and won't conduct. I'll have to work my courage up once it gets here. Sticking anything in an outlet except a plug goes against everything my mother told me as a child!


Posted By: jmsokol
Date Posted: 07 Jul 2014 at 11:03am
Originally posted by Bulldogpod

jmsokol, that was you in the video? What a great segment. I subscribed after watching it on youtube. Thanks techntrek for posting, I ordered the Fluke 1AC today that you recommended. I am still a little shy about testing it on the outlet itself, even though I know it is plastic and won't conduct. I'll have to work my courage up once it gets here. Sticking anything in an outlet except a plug goes against everything my mother told me as a child!

Yes, that's me in the video. I'm also supposed to be doing some newspaper interviews this week and perhaps a national news piece.

As far as poking a NCVT into an outlet to check for polarity, those tester are rated for up to 1,000 volts, so not to worry. I've done it many thousands of times and have complete confidence in using a NCVT that way. Also, I'll be posting an article about selecting NCVTs for this usage in next week's RVtravel newsletter. It's basically an excerpt from my new eBook No~Shock~Zone RV Electrical Safety. Please pass the book ink and article info onto everyone you know with an RV. We certainly don't want to see another preventable tragedy occur. http://www.amazon.com/dp/B00L2DWBD8 - http://www.amazon.com/dp/B00L2DWBD8




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mike@noshockzone.org
www.noshockzone.org


Posted By: techntrek
Date Posted: 09 Jul 2014 at 12:11am
I pulled out my testers tonight while setting up camp (near Great Sand Dunes in CO) and discovered that there is no ground.  Same for a dozen other sites (all empty so it was easy to check).  I made it down to the site next to the next camper a half-dozen sites away and was still getting a missing ground reading, so I asked them if I could check their site.  Happily they were ok, probably on a different panel.  I showed them the outlet tester and VoltAlert and why they are necessary.  They are considering a pod so they may show up here at some point.

Anyway, this is only the 2nd campground with hookups on this trip and already I've found an issue...


-------------
Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: jmsokol
Date Posted: 09 Jul 2014 at 6:40am
Originally posted by techntrek

I pulled out my testers tonight while setting up camp (near Great Sand Dunes in CO) and discovered that there is no ground.  Same for a dozen other sites (all empty so it was easy to check).  I made it down to the site next to the next camper a half-dozen sites away and was still getting a missing ground reading, so I asked them if I could check their site.  Happily they were ok, probably on a different panel.  I showed them the outlet tester and VoltAlert and why they are necessary.  They are considering a pod so they may show up here at some point.

Anyway, this is only the 2nd campground with hookups on this trip and already I've found an issue...

Great work. And that's why I tell everyone to test every hookup every time. You just don't know if something has gone wrong with campsite power either through lack of maintenance or incompetent wiring.

It's important to realize that an open ground on a power outlet is likely what caused the death of the 3-year-old boy in Amboy, IL last week. I've talked to the sheriff that investigated the accident, and their electrician confirmed the open ground. I'm trying to nail down more information and have a call into the electrician himself. Remember, you don't need a secondary fault to electrify the skin of an RV if your EGC/Ground has opened up. There's sufficient normal leakage from your RV's appliances and electrical system to generally bias the skin of your RV to around 60 volts and several mA of current, perhaps even 10 mA or more. That's enough to kill a small child or old adult with a weak heart. And if there's an additional line-to-chassis fault current from something like a pin-hole leak in a hot water heater element or water in a junction box, then your hot-skin voltage source and be a few amperes. That's enough to kill anybody.

And this allows me to introduce yet another concept to you all, something I call a "Reflected Hot Skin". There's a high probability that this particular group of campsites have their EGC Grounds connected together via daisy chaining, but that the final run of the ground wire back to the main service panel has failed for some reason. So now you have perhaps a dozen campsites with their "grounds" connected together, but there's no connection back to the service panel's neutral-ground-earth bonding point. This allows a line-to-chassis fault in one RV to not only hot-skin energize its own chassis, it WILL cause hot-skin voltage on ALL other RV's connected to the same loop. And while a voltage monitoring system  should alert you of the fact that your ground is compromised, it can't disconnect you from a now energized safety ground wire feeding your RV skin with voltage. This explains why some of my readers claim they had no hot-skin voltage when they initially plugged into a campsite, but the next day they were feeling a shock. But, of course, a NCVT will find the now electrified RV skin and chassis. It's cheap insurance that can save your life.

Of course, if you campsite pedestal is properly "grounded" then there's zero possibility of some of RV electrifying your own RV chassis/skin. That's why it's important to test every time before plugging into shore power.

As always, contact me if you've found anything suspicious and I'll help you figure it out.


-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: Bulldogpod
Date Posted: 09 Jul 2014 at 7:14am
Will my fluke pen be enough for a good check at my site? Do I need to buy a voltmeter and polarity tester too? I hadn't done that, frankly, because I am most definitely NOT an electrician, and don't know how to use that equipment properly. But if it keeps my family safe, I will learn.


Posted By: Leo B
Date Posted: 09 Jul 2014 at 7:28am
I agree with Bulldogpod. Is there a safe method for non-electricians?

-------------
Leo & Melissa Bachand
2017 Ford F150
2021 Vista Cruiser 19 csk
Previously owned
2015 Rpod 179
2010 Rpod 171


Posted By: jmsokol
Date Posted: 09 Jul 2014 at 8:05am
Originally posted by Leo B

I agree with Bulldogpod. Is there a safe method for non-electricians?

Ideally, you'll have a digital voltmeter, a 3-light outlet tester, and a Non Contact Voltage Tester. You can buy the full set of Klein meters at Home Depot for $35. http://www.homedepot.com/b/Electrical-Electrical-Tools-Accessories-Electrical-Test-Meters/Klein-Tools/N-5yc1vZboffZ3xg - http://www.homedepot.com/b/Electrical-Electrical-Tools-Accessories-Electrical-Test-Meters/Klein-Tools/N-5yc1vZboffZ3xg

While I use lot of Fluke gear on my test bench (I'm a EE), I find that the Klein gear is a good second choice for consumers and available at any Home Depot.


However, while you don't need to be an electrician to test safely, you DO need to understand electricity. I recommend that everyone with an RV purchase a copy of my eBook No~Shock~Zone RV Electrical Safety. It's the best $10 you'll spend this year. http://www.amazon.com/dp/B00L2DWBD8 - http://www.amazon.com/dp/B00L2DWBD8 So please pass this info on to everyone you know with an RV.  I'm also finishing the print version of this book which should be available in a few weeks. In the meantime, you can download and read the Amazon/Kindle version on any tablet, iPad or computer using a free kindle reader.

I'm now working on a set of videos for RVtravel.com that will detail how to safely test a campground pedestal for correct power. For that I'm building a failed-pedestal simulator that will allow me to create all sort of mis-wiring conditions and demonstrate how to test for them. So stay tuned.

You can also help by suggesting to your rpod dealer and Forest River that they support my No~Shock~Zone articles and videos. There's only so many campers I can reach one forum at a time, but if Forest River would get behind this effort, then a lot more lives would saved.



-------------
mike@noshockzone.org
www.noshockzone.org


Posted By: kymooses
Date Posted: 09 Jul 2014 at 9:42am
Originally posted by techntrek

I pulled out my testers tonight while setting up camp (near Great Sand Dunes in CO) and discovered that there is no ground.  Same for a dozen other sites (all empty so it was easy to check).  I made it down to the site next to the next camper a half-dozen sites away and was still getting a missing ground reading, so I asked them if I could check their site.  Happily they were ok, probably on a different panel.  I showed them the outlet tester and VoltAlert and why they are necessary.  They are considering a pod so they may show up here at some point.

Anyway, this is only the 2nd campground with hookups on this trip and already I've found an issue...

So in this case Tech, what did you do, did you contact the campground, did they send someone out to fix all of it?  Did you yourself not hook up power at all at this campground at all?




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Posted By: techntrek
Date Posted: 10 Jul 2014 at 12:42am
For non-techies, at the very least get the plug-in tester and the non-contact tester (the items to the right and bottom in the picture Mike posted above).  It literally takes 60 seconds to use both and they don't require any interpretation.  With the ones I have I should get a green light on the plug-in tester and no light (or beeping) from the non-contact tester.  If I don't get a green light there is a chart right on the tester which tells me what the lights mean.  Using a voltmeter gets a little more technical, interpreting numbers, etc.

kymooses, I spoke with the campground owner the next morning and explained that she had a very dangerous situation and needed to call her electrician immediately.  That was the soonest I could tell anyone since the office closed before I discovered the problem.  In this case I knew I didn't have an immediate problem since the VoltAlert was negative (no electrified chassis), and we were already set up, so I stayed hooked up long enough to charge some things.  Since we didn't need to run A/C we didn't need it after that, and if we did I would have moved to one of the sites with a good connection.  They had plenty of open sites so it wouldn't have been a problem.


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Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ http://www.rpod-owners.com/forum_posts.asp?TID=1723 - Pod instruction manual


Posted By: Bulldogpod
Date Posted: 10 Jul 2014 at 8:01am
Thanks, guys! I really appreciate the help.



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