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KiCar6375
08-15-2012, 12:22 PM
In 2008, my husband and I purchased a new 2007 Trail Runner. We went from apop up camper to a pull behind RV and we felt we made a very gooddecision. Since then we have welcomedtwo sons and have been camping thru the summer & fall months.

Last week we had the unit plugged in at home & we weregetting ready to head out for the 4th of July weekend. My Aunt & my oldest son went out to thecamper, so that she could see the inside. They both went in with no problem. Next, my youngest son (who just turned 2) went up to the camper. He had just climbed out of the pool, so hewas wet. He leaned against the step andwas getting ready to climb up. All of asudden he jumped back and started to scream & cry. I thought that the step was hot and that heburnt his stomach. So, I am standing therelooking at his stomach and trying to calm him down. All of a sudden my husband (who is also wetfrom the pool) leans against the step and starts acting funny. He was all leaned into the camper and he letout a scream. I didn’t know what washappening. All of a sudden he goesflying across the yard. He is now layingin the yard and he is jerking and convulsing around. He gets himself somewhat under control andyells for someone to unplug the unit. Asit turns out he was being electrocuted! Which means that my 2 year old son did NOT get burned, as I thought, hegot shocked. This could have ended verybadly for our family and we are thankful that everyone is fine. My boys were scared to death to see theirdaddy lying on the ground like that. Itwas a very freighting thing to witness. We called my dad over who is a Master Certified Technicianhere in the Elkhart area. He wastroubleshooting the problem and measuring out the voltage. It turns out my husband had 110 volts shootthru his body. I thank god my 2 year olddidn’t lift his leg, because I can guarantee he could not have handle 110 voltsthru his little body. Anyways, my daddiscovered that the element in the water heater was bad. Basically, that problem was causing theentire trailer to be “live” & my husband being wet made it worst.
So, here’s my problem. As I’ve said before, this could have had an entirely differentending. A neighbor kid could have beenelectrocuted, my children could have been electrocuted & my husband wasalmost completely electrocuted. If wehad been at a campground when this happened and some random child touched ourcamper, could you imagine the outcome? Shouldn’t this trailer be equipped with some sort of sensor that makesit blow a breaker when there is a problem? Isn’t there some sort of safety prevention? If there are safety procedures in place, didour camper mal function? I understandthat our warranty has expired, but if this is a common occurrence within RV’sthan I think it needs to be corrected. Idon’t consider our RV to be ancient & understand that it has to bemaintained, but I think we need a little warning. A breaker that keeps tripping or no hotwater, something a little better than being knocked on your butt by anelectrical shock.
My husband is now completely freaked out by the camper &we are considering trading it in. Theproblem with trading it in is that we wouldn’t feel right about trading acamper that has issues. What if thissame thing happens to the next family that owns the unit?

We have been in talks with Heartland. The first gentleman we talked to was very sympathic, the second gentleman basically told us where to stick it and the 3rd guy told us that since our unit is older we can expect problems. In his opinion, a bad heating element that almost eletrocuted 2 people in my family is normal. He then proceeded to tell us that we could have purchased an additional add on that would ensure that if we had a problem with our camper the breaker would trip and shut everything down. Now, is it just me or does anyone else think this should be standard issue??

In my own personal opinion, Heartland is so concerned with pushing out units and making money that they are foregoing important safety checks. If our unit would have been inspected they probably would have caught the electrical problem.

I just want to put that warning out there to people. If you google "electrocution by RV" it will bring up tons of stories many of which are fatal.

danemayer
08-15-2012, 12:55 PM
KiCar6375,

First of all, let me say that I'm sorry this happened to your family. This must have been a horrible experience for you.

I'm not an electrician, but I'm pretty sure you have a 2nd problem beyond the failure of the water heater element. I'd hazard a guess that the ground line on your trailer, or on the power source, also had a failure. The design of 110V AC devices is such that a failure leading to an unsafe condition should be neutralized by the grounding in your trailer. That is, if 110V is applied to the trailer body by a failing device, the electricity should take the easiest path to ground, which by design is through the trailer ground wiring to the power supply at the pedestal. If the electricity's easiest path to ground was through a person, it usually means there's a failure in the grounding wiring.

Since you were plugged in at home, this might be caused by a bad extension cord, or improperly wired outlet, having nothing to do with the trailer itself. For example, if the ground pin was broken off the extension cord, that would interrupt the ground path. Then when the heating element shorted, there was no way to take the electricity to ground, except through the people who touched the trailer body.

Yes, it could also be a problem with the trailer wiring - maybe the ground wires came loose somewhere.

Anyway, my main point is that you need to get a qualified electrician to find out where the 2nd problem came from. Fixing the water heater alone will not be sufficient.

kakampers
08-15-2012, 01:03 PM
Very sorry to hear this happened to your family...but I have to ask, when was the last time your water heater element was checked?

For the entire coach to be "live", something would have had to short out causing it to "ground" thru the frame. The water heater has a sacrificial rod that needs regular replacement to protect the tank and the element from corrosion...this needs to be check at least once a year. This is an industry wide standard, and if maintained, the water
heater should not cause any shock issues.

Again, very sorry this happened and hope everyone is OK...

danemayer
08-15-2012, 01:29 PM
Some additional information about RV Electrical Systems and how they are designed to protect you from what happened when the ground system is working. I've highlighted 2 portions.


Safety PracticesGroundingGrounding ensures electrical safety. Grounding can be divided into two areas: 1) system grounding, and 2) equipment grounding. System grounding is the intentional connection of a current-carrying conductor to ground (earth) or something that serves in place of ground (vehicle chassis). System grounding does not occur in the RV but is accomplished when the power cord is connected to a power pedestal in the park or some other power supply receptacle, where the neutral is intentionally grounded. Equipment grounding is the intentional connection of all noncurrent carrying metal parts of the electrical system to ground. In the RV this is accomplished by the ground wire in the conductors of the 120 VAC system. There are four reasons for grounding:1. To limit the voltage caused by lightning or by accidental contact of the supply conductors with conductors of higher voltage.
2. To stabilize the voltage under normal operating conditions.3. Grounding provides a low resistance electrical path for current flow, so if a person comes into electrical contact with a piece of equipment, the current will follow the ground path to complete the circuit instead of flowing through the higher resistance of the human body.4. To facilitate the operation of overcurrent devices such as fuses, circuit breakers, or relays, under ground fault conditions.Grounding SystemRVs are wired differently than houses and the differences are based on the grounding system. In an RV, the white or neutral conductor is isolated from the ground conductors. This means there is no electrical interconnection of the white wire and the bare ground wire in the RV. These two wires are not interconnected until connected at the power supply at the park pedestal or other suitable power source. In a house, the white and ground wires can be interconnected without concern because in a house, polarity cannot be reversed. Reverse polarity occurs when the white and black wires are crossed. In an RV, the power supply cord or power supply adaptor plug can provide reverse polarity. This is especially possible where someone cuts off the ground pin of the cord or uses an ungrounded (2-wire) extension cord. In a situation of reverse polarity where there is also a short, the power could be “fed” to the white wire, by passing the overcurrent protection provided,energizing the exterior skin or other metal parts leading to severe burns or possibly death. In normal operation, the electric circuits function the same way with or without the ground, but the grounding is an important safety precaution. Figure 6-1 shows one type of plug/receptacle for the AC power line that helps in providing protection because they are polarized with respect to the ground connections. Although AC voltage does not have any fixed polarity, the plug’s configuration insures grounding to the chassis or frame of equip-ment, connected at the power source. The illustration shows two slots for the 120 VAC load connector. One blade is wider and will fit only the side of the outlet that is connected to the neutral wire. This wiring is standard practice. The rounded pin is for a separate grounding wire, usually bare or color coded green. If the polarity of a circuit is questionable, use a ground monitor (polarity tester) to check the wiring polarity of all receptacles.

evolvingpowercat
08-15-2012, 02:45 PM
The trailer has many electrical gadgets that can fail and put live electricity to metal. There are two types of protection, a current limiting circuit breaker and a Ground Fault breaker. Only the Ground Fault kind will trip at 5 thousands of an AMP difference in current flow between white wire and black wire, protecting people and pets. The current limiting kind may allow a hazard voltage to appear if the ground has too much resistance in it. This can happen in an older home where the ground is not a physical wire but uses rigid or flexible conduit for the return path and the current has to pass thru many mechanical connections that can have too much resistance with time due to corrosion or working loose. The current limiting kind even with a good ground can still cause enough voltage to be hazardous on metal in your RV and in particular in your case where the person was wet and not wearing shoes. In some other cases current flow is not enough to trip the breaker but enough to get something overheated and start a fire. The current limiting breaker is sized to prevent only the wire from the breaker to the load from catching fire. That said, there are many things where the RV Code and National Electrical Code require only the current limiting kind to be used, so Heartland meet all the codes and it is up to you if you want to go "above the code" or not.

I suspect that the water heater in your RV must not be on a ground fault breaker. And certainly based on what happened your house circuit feeding the RV is not on a ground fault or if it is, it has failed and needs to be replaced.

To give yourself a better sense of security in the future I suggest you change your house breaker that you use with your RV to a ground fault type. These are available for any size 110 V service your RV outlet uses: 15 A, 20 A or even 30 A.

You can buy a outlet tester with a GFCI test button that causes a 6 mA black to ground current that trip a good GFCI to make sure its working. This is better than just using the GFCI test button. Having a outlet tester will warn you in the future if your have an open ground in your power source, and if the GFCI in the power source is good. To use it, you just plug it into any outlet in your trailer. If you have a big trailer with 50 Amp service, then you may have to plug in two places to check both sides of the 50 Amp 110 V service. You can also plug it into the 110 volt outlet in your home that you had the trailer plugged in to, if that was the case.

This will help you tell if its outlet issue, or cord issue.

It sounds like your dad should be able to help you out with this trouble shooting - be safe and don't plug that trailer back in until you get to the bottom of it.

evolvingpowercat
08-15-2012, 03:52 PM
This is what you need to tell if your power in your RV is wired safe, and if the outlet you are using (if 15A or 20A standard) are safe. The button is what generates the simulated fault from hot to ground to make sure the GFCI trips like it should.

There are several makers - these cost about $10.
http://ecx.images-amazon.com/images/I/71TkQqEhHtL._AA1500_.jpg

scottyb
08-15-2012, 05:59 PM
I got buzzed yesterday while crawling around under the trailer on the damp ground. Called a few smart people and I have verified that my feed coming into the well house is only a 3-wire. The RV service is wired correctly with a 4-wire conductor. I will be installing a ground rod to the neutral lug in the breaker box this weekend. the first couple times were just a tingle then a couple were more of a jolt, like an electric fence. We determined it was a problem with the shore power because it didnt do the same thing on generator power. It stopped as soon as I disconnected the shore power.

wdk450
08-15-2012, 08:15 PM
I skimmed over the replies, but the number one thing I can tell you is that electrical devices connected outdoors need to be connected through a ground fault protected circuit. I would have to ask if you were using a standard houseshold 15 amp circuit, or an RV specific 30 or 50 amp service. 15 Amp GFI outlets are commonly available, and are code for wet and outdoor locations. 30 and 50 amp GFI protection can be obtained through GFI circuit breakers.

Your best protection is to have the GFI at the source of power to the load (the trailer). I just participated in a survey of medical equipment maintainers about how often and with which what equipments we found electrical safety problems (we check medical equipment for this yearly. We test with a special tester that disconnects the ground wire to simulate a common broken ground in equipment that is repeatedly plugged and unplugged. Medical devices must meet electrical leakage requirements without the ground being present). Electrical immersion heaters were one of the few frequent causes of high electrical leakage, due to their being out of visual sight and subject to various rates of corrosion.

I am so sorry that this happened, and am thankful there was no permanent physical harm to anyone. Get the heater fixed (simple DIY job), flush the heater yearly, and get those GFI protectors on the electrical supply to the trailer.

BTW, the GFI's DO work on the trailer. I was staying in a small park in the Seattle area last year, and was only supplied with a 15 amp GFI protected service. One morning the GFI tripped repeatedly after I used the convection/microwave. I finally deduced that the convection/microwave produced a lot of steam cooking the food, which got to some of the microwave internal AC circuit wiring, producing enough electrical leakage to trip the outside service outlet GFI. Air drying out the microwave (with the microwave circuit breaker switched off) solved the problem.

RollingHome
08-15-2012, 09:00 PM
We all are sorry this happened to you. You may not want to hear this, but sometimes when things happen they are a blessing in disguise. Yes what happened is terrible, but as you stated worse has happened to others. You received some good advice already. However, the best advice came from Dan Meyer right away. He suggested you get a licensed electrician involved.
I’d like to offer some more advice; first, I am a licensed master electrician and more. If your home was built before 1972 it is grandfathered, which means you are not required to have GFCI’s installed anywhere in your home. This does not mean you don’t need them – you do. If your home is real old you may not even have 3 wire circuits, which means you have 2 wire circuits – A hot and a cold (neutral) or a black & white wire. If this is the case I would suggest having the electrical service upgraded. You need to have 3 wire circuits and you need to understand the green wire (also known as the ground) is the most important wire you can have. The only time it is needed is when the exact thing that occurred to you folks happens. It is highly likely you have a ground problem or no ground at all.
If your home was built after 1980, then you have some serious wiring issues which need attention NOW by a licensed electrician. You should also considering going to Camping World or Tweetys Or, Or, Or and purchasing a surge protector with ground fault protection and use it at home and on trips. Last year we camped at a park which had 80 volts AC coming into RV’s due to a wiring fault in the park. 80 volts AC can be lethal – it has killed people. Several campers were getting tingles... until my wife touched a unit and received a severe shock. I measured the stray voltage and called park maintenance. They found a short in a box in the systems wiring. Do not let this scare you from camping, instead let it be a learning experience that you can share with others as you be your brother’s keeper.
Finally, in closing, anytime this type of thing happens you should take the persons affected to the nearest ER room as soon as you can. Calling an ambulance would not be over reacting because some damage may have been done – you just don’t know. In fact, I still would take your husband to at least see your PCP or family doctor. I’m not trying to scare you, it’s better to be safe than sorry. Good luck, God bless and keep up posted.
I try to end my post with Happy Rving, the next time you post I hope I can.

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StephenKatSea
08-15-2012, 09:12 PM
There have been many good observations on this extremely serious situation. But, I'm really not sure that a wasted water heater anode rod could actually cause electrical shock. I don't believe these anodes have any electrical connection. They are merely composed of "less noble" (sacrificial elements) metals per the Periodic Table. Could depletion of the anode actually lead to sufficient corrosion causing failure to the electrical portion of the water heater to the extent of potential electrocution? IF that is truly the case, then more emphasis and "WARNING" MUST be placed on this simple anode replacement.
Very sorry to hear this happened to your family...but I have to ask, when was the last time your water heater element was checked?

For the entire coach to be "live", something would have had to short out causing it to "ground" thru the frame. The water heater has a sacrificial rod that needs regular replacement to protect the tank and the element from corrosion...this needs to be check at least once a year. This is an industry wide standard, and if maintained, the water
heater should not cause any shock issues.

Again, very sorry this happened and hope everyone is OK...

RollingHome
08-15-2012, 09:25 PM
Stephen, the short answer is yes. BUT... Anodes as you stated are sacrificial. Once they have depleted they have no more to give and hence, any other metal starts giving, the tank (if not glass lined or fractured), the drain, and yes the heating element “IF” it has metal in contact with water. I have seen anodes gone in a month if serious stray voltages exist. You would be amazed at what can happen. In a marina I saw a boat pulled and half the casing of the lower unit of the outdrive was gone ! Changing or checking anodes yearly is a must do.

JohnDar
08-15-2012, 09:27 PM
There have been many good observations on this extremely serious situation. But, I'm really not sure that a wasted water heater anode could actually cause electrical shock. I don't believe these anodes have any electrical connection. They are merely composed of "less noble" (sacrificial elements) metals per the Periodic Table. Could depletion of the anode actually lead to corrosion and failure to the electrical portion of the water heater ?

It's not the anode rod that seems to be the culprit, but the electric heating element. But, I'm not sure how that would short to the frame if it was bad unless it was replaced at some time and not installed correctly. Not saying it couldn't, but unless it suddenly went bad, I'd think that even without the wet feet from the pool, you might get a tingle from a short to the frame if you touched it.

porthole
08-15-2012, 09:49 PM
1 post

wdk450
08-16-2012, 09:19 AM
John and All:
The anode is known as a "Sacrificial" anode (usually made of zinc). Zinc is more suseptable to corrosive forces than most other metals, so the corrosion happens on the zinc anode first, and then will happen on the other metal surfaces after the zinc is gone.

When the metal coating of a heating element is eaten away ( many of the holes are just small pits) the electrical conductor is directly exposed to the water it is immersed in. The electricity is conducted through the water to grounded metal surfaces in the tank (i.e. the remaining heater element sheathing). If there is enough current leaking, and good ground path, a circuit breaker somewhere should blow. Unfortunately, the current through water encounters a relatively high resistance and it is hard to get the 10 amps or so of leakage to trip the heater breaker. But, just 1/2 of an amp of electrical leakage can kill you. Add a grounding resistance through long cords or poor connections, and your body is a better path to ground than the wiring.

When a GFI device measures an imbalance in the current going out the hot wire and the current returning on the neutral wire of 20/1000 of an ampere or more (current assumed to be running through a shocked person's body), the power is shut off in less than 7/1000 of a second. See this link:
http://www.2d2c.com/gfci.php

I hope this helps.

brianharrison
08-16-2012, 09:26 AM
1 post

+1 - lots of good information in the replys - hopefully the OP is still here and uses it to help the situation.
Brian

JohnDar
08-16-2012, 09:50 AM
Bill, the sacrificial anode rods for water heaters are either magnesium or aluminum. Zinc is used for marine applications, like on my outboard motor. From other reading, Mg is preferred in water systems over Al due to possible toxicity concerns. But, they are basically passive devices, not powered. I've been trying to find construction details on the heating element, but no luck so far. But I don't know that they have a sacrificial coating over the element (like an anode rod). I think they're like the grand-daddies of the little electric heating elements you can stick in a coffee cup to heat the water. A metal tube that heats by electrical resistance.

This all fun academic stuff. The real concern remains why did the water heater element pass current to the frame of the trailer and almost electrocute some people. If this is a possibility as rigs age, what is the preventative measure to guard against it?

danemayer
08-16-2012, 10:56 AM
The real concern remains why did the water heater element pass current to the frame of the trailer and almost electrocute some people. If this is a possibility as rigs age, what is the preventative measure to guard against it?

All electric devices have potential to malfunction, short, have insulation wear off the wires, etc. The preventive measure that guards against electrocution is proper grounding throughout the trailer and it's power source.

As mentioned, an additional level of protection against problems with the power source is to add an electrical management system like this (http://www.campingworld.com/shopping/product/portable-surge-protector-with-voltage-protection/9614) that protects against wiring problems at the campground pedestal or other power source.


lots of good information in the replys - hopefully the OP is still here and uses it to help the situation.
Brian
Good point - lets all resist the temptation to wander into side topics.

TandT
08-16-2012, 11:39 AM
When I first saw the title of this thread I was horrified.

Thankfully the OP's family members were not electrocuted, but shocked instead.
According to Webster & Wiki, electrocution is death by electrical shock.

As others have said, hopefully this will alert the OP and others to potential problems from not having your rig properly grounded,as it sounds like that was most likely the case.

Best of luck to the OP and hopefully there are no lingering effects from the incident. Trace

jbeletti
08-16-2012, 11:49 AM
Very sorry to the OP for what happened to their family. Very scary and dangerous. Thanks to all who've given some great advice on things to check. Hoping the OP is watching their thread. I too looked up the definition of Electrocution and decided to edit the Thread Title to Electric Shock. Not meaning to take any of the seriousness away from what happened to the OP, but just trying to call this what it was. I hope we all hear what the final resolution to the problem was so we can all learn from it.

evolvingpowercat
08-16-2012, 12:42 PM
Here is what we all can do to check for any conditions at our RVs that would indicate a danger exists...

Here is a simplified picture of how 110 Volt AC is fed to your camper. Note that there is a second "leg" of 110 Volts from the Power Utility fed into your home I have not shown, that is not applicable since your RV only uses 110 Volt AC so is only tied to one of the two "legs".

Generally you RV is isolated from earth ground by your tires and by the blocks you have under your tongue jack to distribute its weight. Don't connect your camper to AC yet. Prepare to measure the voltage from your trailer to the ground at your trailer. Connect one side of the AC volt meter to the camper frame, the other side to a ground rod. A metal tent stake driven 6" into the ground will do for this. If ground is very dry dampen the earth at the stake.

Now not touching the camper, connect the camper to AC and read the AC volts between the camper frame and earth ground. If you read more than 0.3 volts AC, then someone connecting earth ground to the RV with wet skin on both contact points may feel a perceptible shock. Dry skin requires a higher voltage to feel a shock and to cause enough current to flow to cause injury.

Anything 3 volts or over can cause someone or something with wet skin connecting earth ground to the RV to cause 10 thousands of an amp of AC current to flow, enough to cause death in worst case scenario for the most sensitive child or females adult.

Note: if you read voltage - read post #21 (one newer than this) in this thread. Your volt meter may not be putting enough load between chassis and earth ground and the voltage "could" be a false positive due to voltage due to stray electromagnetic fields from nearby powerlines influencing your RV. You can re-test with a 10,000 ohm resistor load between chassis and earth ground per post # 22 to see if it is just a false positive.

If one of the breakers in the path of the AC voltage source is a Ground Fault Circuit Interruptor (GFCI) it will open the breaker if as little as 5 thousands of an amp is sensed to flow out the black wire without returning on the white wire.

Reference: Conduction of Electrical Current to and Through the Human Body: A Review http://www.eplasty.com/index.php?option=com_content&view=article&id=345&catid=170:volume-09-eplasty-2009



http://i1055.photobucket.com/albums/s508/evolvingpowercat/Drawing1.jpg

evolvingpowercat
08-16-2012, 01:13 PM
One comment on my prior post - I forgot about the fact that most modern digital volt meters don't put enough load between the camper frame and ground rod to dissipate stray voltage caused by electromagnetic fields in the world around us. These may cause a measurable stray voltage but can't produce enough current to feel or do harm. Here is an updated diagram if you read a voltage and want to see if it is harmless. Put a 10,000 ohm resistor between the same two places you connected your AC meter. This is simulating the kind of load that a person with dry skin would put between the RV and the ground so the voltage you read with this resistor there is what is important to know and deal with if it is over 0.3 volts AC.

http://i1055.photobucket.com/albums/s508/evolvingpowercat/Drawing1-1.jpg

kakampers
08-16-2012, 01:24 PM
WOW, Randy...thanks for this great detailed information! Next time we have an electrical issue in our coach, I know exactly who I'm looking up....

RollingHome
08-16-2012, 02:39 PM
There was/is question about the mechanics of heating element construction. These I suppose are to answer the OP as to how (exactly) this could have happened. There was also discussion how/why the anode fits in. Here is how most are constructed. There are various attachments to the device (water heater) some screw in, some have a flanged bolt pad and some are integral to the unit being heated. The point is, they are attached and provide an excellent path to ground for stray voltage “IF” the ground is good. Past the attachment is what is commonly called a calrod. This is a generic name for the following. The elements have 2 conductors, hot & neutral (black & white). The wires attach with nuts or screws. The calrod is actually a case (conduit) usually made of metal or ceramic. Inside the calrod is nickel chromium wire commonly known as Ni-chrome wire. This Ni-Chrome wire is what heats the water when voltage is applied. Immediately surrounding the Ni-Chrome wire is silicon sand – just like white beach sand. The sand insulates the Ni-Chrome wire from the outer case and prevents burn through because it takes about 3000 F to melt it. This is basically how all heating elements are constructed. This is the general construction whether they are in your electric baking oven, water heater or other device.

If the anode is not replaced and is eaten up, the next thing to dissolve is usually the heating element. This is why it is important to replace the anode yearly.

JohnDar
08-16-2012, 03:23 PM
Thanks for the info on the element construction, Tom, I was interested in it. But, it sounds like one of the first levels of prevention is regular inspection/replacement of the anode rod. For those of us that winterize our rigs, it's necessarily part of the process. I would wager that most of us don't even think about the condition of the element until it stops working. From strictly a curiosity standpoint (used to do a fair amount of failure analysis), I'd like to know what the OP's heating element looks like, but thoroughly understand they would not be of a mind to satisfy that curiosity.

Also glad they were only shocked, albeit seriously, and not electrocuted.

evolvingpowercat
08-16-2012, 09:22 PM
> This all fun academic stuff. The real concern remains why did the water heater element pass current to the frame of the trailer and almost electrocute some people. If this is a possibility as rigs age, what is the preventative measure to guard against it?

Preventative measures:

Electric Hot Water Heater on a GFCI protected circuilt. The trailer electrical box may take GFCi breakers if so the breaker in the RV could be replaced with a GFCI type one. Or the whole trailer could be protected with a GFCI equipped surge supressor in line with the power cord or the kind that is permanently hard wired in the travel trailer. These solutions have the advantage of working anywhere you are, on either a generator or shore powered outlet.

jimtoo
08-16-2012, 11:57 PM
There has been lots of great information posted here about preventive measures, checking procedures and remedies. But I would like more information from the OP.

The OP posted, "Last week we had the unit plugged in at home & we weregetting ready to head out for the 4th of July weekend."..

My questions are:

Is the trailer normally stored at home where it was located at the time this happened?
Was the trailer plugged into a 15 amp, 20 amp, 30 amp, or 50 amp circuit?
What kind of cord was used,, regular one that came with trailer,, or some other type of extension cord?
Was the water hooked up and turned on? Was the water heater full of water?
Did the water heater work on electric the last time it was used?
After the event happened, was the trailer unplugged and then plugged in again when the checking was started?
The 110v that was measured,,,was it from trailer body or frame to ground or how and where was it measured?

I think we need some answers from the person or tech that did the checking and determined what was causing the problem.

Jim M

porthole
08-17-2012, 06:44 AM
If it looks like a************ .............................

Still only one post.

If you want to know what the comment that was censored out was (unnecessarily so) - pm me

katkens
08-17-2012, 08:13 AM
If it looks like a**************...........................

Think I have to agree , poster has been back on with no further comments.......

jmsokol
08-17-2012, 08:25 AM
I'm the author of the No~Shock~Zone website (www.noshockzone.org (http://www.noshockzone.org)) and have experimented and written extensively about hot-skin conditions on RVs. Unfortunatley, a lot of what's already been answered on this thread is hearsay and old-wives tales, and much of it untrue. I've written a 12 part article there which is also posted on www.RVtravel.com (http://www.RVtravel.com) about how electricity works and how to test for dangerous conditions.

Here's how the electrical grounding system on an RV really works.

All modern (and correctly wired) RVs will have a safety ground wire in their shore power power plug. This is the little U-shaped or round pin on your power plug. This ground pin needs to be "bonded" to the frame of your RV (inside your power panel) so that it provides a low-impedance (short-circuit) path from the RV's frame/skin to the ground-bonding point in the incoming electrical service panel. It's job is two-fold... first it's there to drain off any small leakage currents inside your RV from appliances. It's also there to trip the circuit breaker if you pinch a wire in a box, creating a direct short to the appliance or RV chassis. Int the first instance, these leakage currents can be caused by an aging microwave with its power transformer insulation degraded by heat and vibration, or a pin-hole leak in the heating element of the hot-water heater (sounds like what happened to you). Now, for the safety ground wire of your RV to actually do its job, it must be connected to a properly grounded/bonded power outlet. That way there's a complete circut path from the electrically leaking appliance back to the service panel, where that current will short out at the panel's bonding point, which is where the Neurtal, Ground and Ground rod are all supposed to meet (bond). This works well in principal, but ALL RV's (no matter what the age or brand) can have a hot-skin condition caused by plugging into an incorrectly wired power outlet. The most common failure in a house or garage outlet is that the ground connection is open (broken). This condition allows the chassis and skin of the RV to go to whatever voltage it feels like, which can vary from close to zero (no appliance electrical leakage) to 120 volts (fully energized ground pin). Usually it drifts to around 60 volts AC or so. Here's a video of me electrifying a 40 ft RV with various voltages and testing for a hot-skin condtion: http://www.youtube.com/watch?v=Y8h64X33aKg&feature=plcp

Now not withstanding the previous post about 3 volts being dangerous, I suspect he meant 30 volts as that's the generally accepted minimun electrocution voltage. However, one brief word about using the word "electrocution". To say that you're "electrocuted" actually means you were killed by electrical voltage. You can be "shocked" and not killed, but you can't be "electrocuted" and still be alive.

So I believe that your real problem is an improperly wired electrical outlet in your garage. It most likely has an open ground, which allowed the internal electrical leakage of your hot water heat to bias the chassis/skin of your RV to 110 volts. Fixing your hot-water heater element without correcting the wiring problem in your garage outlet will set you up for a repeat of this terrible event in the future. The next time an appliance in your RV developes some electrical leakage (could be your fridge or microwave next time) your RV chassis/skin will go back up to the line voltage. So have the outlet checked to proper ground immediaty, before plugging anything else into it.

There's also an extremely dangerous outlet condition which I've deemed an RPBG (Reverse Polarity Bootleg Ground). This often occurs when an older house or garage has been "upgraded" to grounded outlets. See http://www.rvdoctor.com/2001/07/friends-of-gary-mike.html for the article I just wrote about this condition on Gary Bunzer's RV Doctor newsletter. An RPBG outlet can't be detected with a 3-light tester (like shown in a previous response), nor can it be detected using a $300 Ground Impedance tester such as an Amprobe INSP-3. You can't even detect it using a volt-meter between Hot-Ground, Hot-Neutral and Neutral-Ground. Everything will tell you it's wired properly and your appliances and RV will appear to operate correctly. However, it will induce a full 120 Volts AC with 50 amp current potential on the frame and skin of your RV. The ONLY way to detect this condition is to either measure from the chassis of the RV to a metal rod driven in the ground (lots of work) or use a non-contact AC test like a Fluke VoltAlert ($25 and easy to do). See http://www.youtube.com/watch?v=iLk-6pvSlWg&feature=plcp for a video where I demonstrate how 3-light testers and ground impedance testers fail to find a RPBG outlet, and how to test for this condition with a NCVT (Non Contact Voltage Tester) such as a Fluke VoltAlert. Here's a video of me testing a small scale RV model for hot-skin condtions: http://www.youtube.com/watch?v=rtT3te_XNBM&feature=plcp and an printable article on the subject as well: http://www.noshockzone.org/rv-electrical-safety-part-iv-%E2%80%93-hot-skin/

Please have your electrician contact me about thesting since I believe he missed the fact that your garage outlet either has an open ground, or an Reverse Polarity Bootleg Ground. And feel free to contact me directly about how to avoild getting shocked from an RV. You were very lucky that nobody was killed, and I've received hundreds of similar emails from around the country about similar events, some of which resulted in death. ANY outlet you plug your RV into should be checked for both voltage and ground conditions, and simply using a $20 NCVT on the skin of your RV right after plugging it into ANY power source will find most (if not all) dangerous hot skin conditions.

Contact me at my email below for clarification of any of this. But be assured, I've done the experiments and published papers about this subject. If anybody ever feels even the slightest electrical tingle from their RV, it could be caused by a failed extention cord, broken dog-bone or pigtail, corroded Ground bonding point in the RV, or a miswired or corroded electrial outlet in your garage, home or campground pedestal. Unplug immediately and have it vetted out from the outlet to the frame of your RV.

Mike Sokol
mike@noshockzone.org
www.noshockzone.org (http://www.noshockzone.org)

kakampers
08-17-2012, 08:42 AM
Mike...I assume my 50 amp Progressive EMS will also detect the RPBG?? I know it detects open grounds...

TedS
08-17-2012, 08:52 AM
Mike, thank you for the correct advice.

Urban350
08-17-2012, 08:58 AM
Mike...I assume my 50 amp Progressive EMS will also detect the RPBG?? I know it detects open grounds...

I hope mine works on everything mentioned in this post also.

wdk450
08-17-2012, 09:02 AM
JMSokol:
Great post on this safety subject. Would you agree with me that one of the weak links in the grounding system might be the power connector to the trailer, that is continually connected and disconnected, thereby causing wear on the connecting surfaces, the internal wires, and loosening the connector wiring screws?

Making the analogy to my hospital electrical safety inspections, bad grounding in power cords was the deficiency we would most often find. Of course, we also tested that the device was still within low electrical leakage specs WITHOUT the ground intact (simulating a broken cord ground).

jmsokol
08-17-2012, 09:04 AM
Mike...I assume my 50 amp Progressive EMS will also detect the RPBG?? I know it detects open grounds...

No it will not!!! I've actually talked to Progressive and a few other manufacturers about this, and none of their products will recognzie an RPBG outlet with with Hot at earth potential, and the Neutral/Ground at 120 volts. And they don't disconnect the safety ground wire in the shore power plug if they trip. So it's possible to have a RPBG induced hot-skin with all the power in the RV turned off. Turning off the circuite breakers in your RV won't disconnect the hot-skin currents either. And if you have a reflected hot skin caused by the campground's unbonded safety ground, and another RV on your branch circuit leg, even turning off the main circuit breaker on your pedestal won't stop the hot-skin condtion. The only way to find a RPBG on a 120-volt outlet is by comparing it to earth, either by measuring the voltage from the RV frame to a ground rod, or by using a NCVT such as a Fluke VoltAlert.

jmsokol
08-17-2012, 09:35 AM
JMSokol:
Great post on this safety subject. Would you agree with me that one of the weak links in the grounding system might be the power connector to the trailer, that is continually connected and disconnected, thereby causing wear on the connecting surfaces, the internal wires, and loosening the connector wiring screws?

Making the analogy to my hospital electrical safety inspections, bad grounding in power cords was the deficiency we would most often find. Of course, we also tested that the device was still within low electrical leakage specs WITHOUT the ground intact (simulating a broken cord ground).

Yes, most certainly!!! All connectors are the weak links in the system, as you well know. So the shore power connector should always be inspected for pitting, corrosion, and loose screws.

jmsokol
08-17-2012, 09:38 AM
I hope mine works on everything mentioned in this post also.

You didn't mentions the brand and model, but I know there's nothing being manufactured currently that will detect and shut off a hot-skin voltage if you're plugged into an RPBG outlet. If any of the manufacturers would like to contact me about it, I'm glad to consult with them on the topic and arrange for a demonstation.

Mike Sokol
mike@noshockzone.org
www.noshockzone.org (http://www.noshockzone.org)

Urban350
08-17-2012, 09:43 AM
It was also the progressive ems, thanks.

jbeletti
08-17-2012, 09:55 AM
Mike,

Thanks for your feedback on this thread. Not sure if we're going to hear back from the OP but I sure hope they circle back and read the thread they started. If the theory holds that they did have a failed AC water heater element that exhibited with current on the frame/skin caused by an open ground on their electrical supply from their house, I just hope they can get that checked out and repaired as well.

I think this is a good learning thread for all in the sense that it points out that AC power source issues can have odd/dangerous effects on the coach in certain circumstances. And of course, this is not limited to power sources at our homes, but also at RV parks. I've heard all kinds of stories from our members about CG power issues, some of which caused issues with equipment in their coaches.

Maybe we all need to look closer at 30 and 50 amp RV receptacle testers that can test for all perils.

Jim

JohnDar
08-17-2012, 09:59 AM
...Maybe we all need to look closer at 30 and 50 amp RV receptacle testers that can test for all perils.

Jim

Does such a device exist? If anyone has a lead on it, please post the link.

jmsokol
08-17-2012, 10:01 AM
I got buzzed yesterday while crawling around under the trailer on the damp ground. Called a few smart people and I have verified that my feed coming into the well house is only a 3-wire. The RV service is wired correctly with a 4-wire conductor. I will be installing a ground rod to the neutral lug in the breaker box this weekend. the first couple times were just a tingle then a couple were more of a jolt, like an electric fence. We determined it was a problem with the shore power because it didnt do the same thing on generator power. It stopped as soon as I disconnected the shore power.
Actually, a separate ground rod won't fix it... and unless it's bonded to the incoming service box's groud/neutral/ground-rod's bonding point, is a serious code violation. The reason for this is simple.... the earth is actually a pretty poor ground. Even a properly intalled ground rod will have something like 25 ohms impedance to earth, and could be up to 100 ohms in dry soil. The ground rod at your electrical service panel is there to drain away lightning-strike voltage, not provide a return path for fault currents in the branch circuits. You need to run a safety ground wire from the ground screw of your outlet back to your service panel's ground-bus. The service panel bond point creates a ground-plane that's CLOSE to earth ground (maybe only by a volt or two), but it's not supposed to be the fault current path, so it's a code violation to use a separate ground rod, not matter how convenient it might be.

Now, a ground rod may appear to fix a high-impedance leakage from something like a microwave's transformer being old. But it probably won't be able to drain off the charge from a pin-hole leak in a hot water heater element, and it certainly will do nothing to trip the circuit breaker in your RV or outlet if you pinch a hot wire under a bolt or box lid. In that case, it may happily send 5 or 6 amps to the earth (120 volts divided by 20 ohms equals 6 amps) which is not enough to trip a 20 or 30 amp circuit breaker. That's why the code requires all ground wires be directly connected back to the service entrance panel.

Mike Sokol

jmsokol
08-17-2012, 10:04 AM
Does such a device exist? If anyone has a lead on it, please post the link.

Sadly, this product doens't exist. I'll be glad to talk to Progressive or any other manfacturer at the Hershey RV show next month. Just give me a heads-up.

Mike Sokol
mike@noshockzone.org

evolvingpowercat
08-17-2012, 10:41 AM
Thanks jmsokol for your excellent post. I have edited my prior post and removed the ground rod mitigation suggestion based on your and others stating that is not a valid solution.

The saftey ground for an RV having to go thru portable cords and several plug/socket connections to reach the ground bonding point in the service panel or generator if dry camping is a reliability concern to me. So I always manually test with a tester like I posted a photo of earlier in this thread when I connect.

Do you think RVIA should require a lighted and audible warning if power is applied to the shore power connector without a good saftey ground ? One would think this could be designed into RV shore power outlets, or into RV electrical service boxes with reasonable cost, the incremental cost should be well under $ 50 with scale. Are you aware of any RV saftey products of this type that are already available for retro-fit?

> Now not withstanding the previous post about 3 volts being dangerous, I suspect he meant 30 volts as that's the generally accepted minimun electrocution voltage. However, one brief word about using the word "electrocution". To say that you're "electrocuted" actually means you were killed by electrical voltage. You can be "shocked" and not killed, but you can't be "electrocuted" and still be alive.

Reference: Conduction of Electrical Current to and Through the Human Body: A Review http://www.eplasty.com/index.php?opt...9-eplasty-2009 (http://www.eplasty.com/index.php?option=com_content&view=article&id=345&catid=170:volume-09-eplasty-2009)

The medical journal article I referenced earlier in this thread said "worst case" body with wet skin completing an electrical circuit could be lethal at 3 volts AC as the resistance path of the person with wet skin worst case is about 300 ohms, allowing 10 mA to flow across the body. The thread started with soaking wet people with bare feet getting a very major shock when entering a RV, so that was the use case I was adressing. The article was very good about documenting how little electrical voltage it takes to shock or harm a person with wet skin making the electrical connection across their body.

The article also stated experiments show some people with wet skin can "feel" current at as little as 0.1 volts, I scaled that to 0.3 volts as a more reasonable voltage to measure.

Given the shock was from trailer to earth next to the trailer, a secondary ground rod next to the trailer would seem to be the way to mitigate that threat for wet barefoot people in particular under all circumstances, one would still be protected even if the saftey ground back to the service panel failed or started to have higher than normal resistance with all of those portable cords and plug/socket connectors in it. I stated "have an licensed electrician do it" because of all the details I am not familar with like the one you mentioned where the secondary ground rods MUST be bonded with proper size ground wire to the primary service panel ground rod.

jmsokol
08-17-2012, 10:58 AM
Do you think RVIA should require a lighted and audible warning if power is applied to the shore power connector without a good saftey ground ? One would think this could be designed into RV shore power outlets, or into RV electrical service boxes with reasonable cost, the incremental cost should be well under $ 50 with scale. Are you aware of any RV saftey products of this type that are already available for retro-fit?



I've talked to the RVIA and RVDA about this sort of thing, and nobody at either organization wants to do anything that would A) add to the cost of an RV which could stop a sale, or B) educate the public about testing for electrical safety since they think it will scare away potential buyers. Yes, it's frustrating, but if enough of you keep asking your RV dealerships about it, perhaps somebody will listen.

I've been consulting with every major test gear manufacturer from Fluke, Triplett, Extech, Ideal, Amprobe, and others about adding RPBG (hot-ground) sensing to their testers, and few of them admitted that the condition could even exist until I showed them my RPBG schematics and demonstration videos, and they repeated the experiments for themselves. Everyone assumes that an outlet will be wired correctly and that it was inspected properly, but in the real world (especially campgrounds and garage outlets) there's rarely any real technical training for the guys doing the wiring. I've consulted on a number of incidents where a licensed electrician accidentally wired an outlet with an RPBG, which then blew up a bunch of sound gear. They came back and retested with a 3-light tester and declared there was nothing wrong with the outlet, but measuring from a cold-water pipe to the ground pin on the outlet showed 120 volts.

More on this later, but I'm trying to put together a national education program about electrical safety around RV's, boat docks with power, homes and business power, and pet safety. I'll keep you posted via updates on www.NoShockZone.org (http://www.NoShockZone.org).

Mike Sokol

evolvingpowercat
08-17-2012, 11:56 AM
Mike, thanks so much for adding to this thread.

Think everyone with an RV should take your advice and get a Non-contact tester to enable them to be able to check for hot skin condition and to check for mis-wired receptacles. I just did!

jmsokol
08-17-2012, 12:10 PM
> Now not withstanding the previous post about 3 volts being dangerous, I suspect he meant 30 volts as that's the generally accepted minimun electrocution voltage. However, one brief word about using the word "electrocution". To say that you're "electrocuted" actually means you were killed by electrical voltage. You can be "shocked" and not killed, but you can't be "electrocuted" and still be alive.

Reference: Conduction of Electrical Current to and Through the Human Body: A Review http://www.eplasty.com/index.php?opt...9-eplasty-2009 (http://www.eplasty.com/index.php?option=com_content&view=article&id=345&catid=170:volume-09-eplasty-2009)

The medical journal article I referenced earlier in this thread said "worst case" body with wet skin completing an electrical circuit could be lethal at 3 volts AC as the resistance path of the person with wet skin worst case is about 300 ohms, allowing 10 mA to flow across the body. The thread started with soaking wet people with bare feet getting a very major shock when entering a RV, so that was the use case I was adressing. The article was very good about documenting how little electrical voltage it takes to shock or harm a person with wet skin making the electrical connection across their body.

The article also stated experiments show some people with wet skin can "feel" current at as little as 0.1 volts, I scaled that to 0.3 volts as a more reasonable voltage to measure.

You're correct from a strictly medical experiment point of view, but both the NFPA 70E (National Electrical Code) and the ARRL (Amateur Radio Relay League) consider the human body's hand-to-hand resistance (under wet conditions) to be between 1,000 and 1,500 ohms, and 30 mA of current across the chest cavity is considered to be nearly 100% certain to start Atrial Fibrillation. The industry accepted low threshold for heart failure brought on 60 Hz AC is 30 volts but if you break the skin barrier or place electrodes close to your heart, it could go into fibrillation at 5 mA or less, but that's really hard to do. That's why GFCI (Ground Fault Circuit Interrupters) are set with a 5 mA to 6 mA tripping threshold.

And certainly if you cut through your skin and touch a nerve with anything even close to 1 volt, you will feel it. Try touching a 9-volt battery to your tongue for a real eye-opener.... (no, it's not dangerous). But it's the heart itself we need to protect from low-voltage (under 600 volt) shocks.

Interestingly, it's DC current at hundreds of volts that's used to restart a heart in Fibrillation (called De-Fibrillation) and that's what happens when the medic yells "clear" and they hit the button. A big surge of DC current is used to reboot your heart and stop if from quivering uncontrollably during an Atrial Fibrillation event.

Most of this I know from my Electrical Engineering training (I was a controls designer and IE for Corning, and used to build Nuclear Missile Guidance Systems back in my youth plus had my Master Electrician's License since 1978), but I've also done a lot of shock experiments on my own, sometimes unintentionally. I was accidentally shocked hand-to-hand with 650 Volts DC, and knocked myself out due to rebooting my heart. And I've had some pretty serious AC shocks in my youth. I just don't want any of you to have to experience that sort of thing (or even worse).

Keep me posted and I'll do my best to help. :D

Mike Sokol
mike@noshockzone.org

JohnDar
08-17-2012, 02:06 PM
Closest thing I know of to test for the presence of A/C voltage without touching it is this thing. We use it whenever we need to determine if a wire is energized. Also use it to determine the charged area around a downed line on the ground or if a vehicle hits a pole and wires are draped on it. These run around $300, though.

http://www.hotstickusa.com/products/achs/ACHotStick_DataSheet_English.pdf

evolvingpowercat
08-17-2012, 02:08 PM
> the NFPA 70E (National Electrical Code) and the ARRL (Amateur Radio Relay League) consider the human body's hand-to-hand resistance (under wet conditions) to be between 1,000 and 1,500 ohms, and 30 mA of current across the chest cavity is considered to be nearly 100% certain to start Atrial Fibrillation. The industry accepted low threshold for heart failure brought on 60 Hz AC is 30 volts but if you break the skin barrier or place electrodes close to your heart, it could go into fibrillation at 5 mA or less, but that's really hard to do. That's why GFCI (Ground Fault Circuit Interrupters) are set with a 5 mA to 6 mA tripping threshold.

Thanks I agree with you - the medical researcher actually had people standing in two buckets of water to create the worst case scenario with only 300 ohms resistance in the current flow path. His research results reported in the paper match your statements in terms of more typicaly "hand touching hot RV skin" scenarios.

evolvingpowercat
08-17-2012, 02:23 PM
Mike, thanks so much for adding to this thread.

Think everyone with an RV should take your advice and get a Non-contact tester to enable them to be able to check for hot skin condition and to check for mis-wired receptacles. I just did!

I got a non-contact tester with adjustable threshold. Home Depot, Lowes, and Ace Hardware don't sell the Fluke kind that Mike recommended, so I got another kind with threshold adjustable between 12 V and 600 V. I just want to know that those that are not "technical" if you buy this "adjustable" kind, you have to "learn" how to use it, so that you don't freak out from false positives.

Personally, I was able to adjust it using a known good 110 Volt receptacle. Mike, this might be another how-to for your youtube collection :-)

Another note, when doing the hot skin test with the adjustable kind like I purchased. It will sense wires in the trailer wall with its sensitivity turned up this is not hot skin. That's one of the things its made for is to warn you if there are live wires in a wall that you are about to start cutting or drilling holes into.

If it beeps on the step or touchng the door handle that's bad. If it beeps with the sensitivity turned up when held near the outdoor outlet most Heartland RV have somewhere not too far from the door that is very likely not bad.

jmsokol
08-17-2012, 02:36 PM
I got a non-contact tester with adjustable threshold. Home Depot, Lowes, and Ace Hardware don't sell the Fluke kind that Mike recommended, so I got another kind with threshold adjustable between 12 V and 600 V. I just want to know that those that are not "technical" if you buy this "adjustable" kind, you have to "learn" how to use it, so that you don't freak out from false positives.

Personally, I was able to adjust it using a known good 110 Volt receptacle. Mike, this might be another how-to for your youtube collection :-)

Another note, when doing the hot skin test with the adjustable kind like I purchased. It will sense wires in the trailer wall with its sensitivity turned up this is not hot skin. That's one of the things its made for is to warn you if there are live wires in a wall that you are about to start cutting or drilling holes into.

If it beeps on the step or touchng the door handle that's bad. If it beeps with the sensitivity turned up when held near the outdoor outlet most Heartland RV have somewhere not too far from the door that is very likely not bad.

Yes, those adjustable ones work as well, but you do have to "calibrate" them against a known voltage source such as a 120 volt outlet. They should beep in the "hot" slot (short one) and not beep in the "neutral slot (tall one), and of course it should not beep in the ground slot. It's possible to get the threshold set so low that they beep anywhere near the front of an energized outlet, which does produce a "freak-out" effect from first-time users. You do have to use a known-good outlet for this calibration test, but any modern home outlet "should" be fine.

Mike

wdk450
08-17-2012, 02:43 PM
In all of the discussion of possible causes of hot trailer skins, we know we don't want this to happen, but if it DOES happen. won't a GFI at the connection point detect the imbalance of current flow in ANY of these situations if a shock occurs and cut the power, thus stopping the electroshock accident???

jmsokol
08-17-2012, 02:53 PM
Closest thing I know of to test for the presence of A/C voltage without touching it is this thing. We use it whenever we need to determine if a wire is energized. Also use it to determine the charged area around a downed line on the ground or if a vehicle hits a pole and wires are draped on it. These run around $300, though.

http://www.hotstickusa.com/products/achs/ACHotStick_DataSheet_English.pdf

Well, the Fluke VoltAlert (which costs $25 and rated from 90 to 1,000 volts) will beep like crazy about 18 inches away from an RV with its body hot-skin energized to 120 volts. If you don't believe it, watch this video of me energizing a 40 ft toyhauler up to 120 volts: http://www.youtube.com/watch?v=Y8h64X33aKg&feature=plcp Once the RV skin is down to 40 volts you'll need to bring the probe tip close to the surface or actually touch the RV with it, but it's a proximity thing as it doesn't care about paint or rust like a standard volt meter with probes does. This experiment is done with a custom kludge cable I built myself and a B&K Precision AC power supply, which allows repeatability of testing with various voltages and NCVT's (Non Contact Voltage Testers). It's a perfectly safe experiment for the RV itself, but of course deadly to anybody sneaking up behind the RV and touching anything metal, so I only do this type of demonstration inside where I can control access to the RV. The tow vehicle is also energized with a 120-volt hot-skin and could kill somebody grabbing the door handle to jump in.

If you want a tester with a longer reach (40 inches) and adjustable sensitivity (down to 5 volts) the Extech DV-50 works very well for less than $50. See http://www.extech.com/instruments/product.asp?catid=31&prodid=520. We're experimenting with this product around boat docks checking for energized conduit and electrical boxes as well as electrified boat shore power connections. There's a voltage gradient effect that reaches out dozens of feet from an improperly grounded boat which can paralyze swimmers and drown them with no sign of electrocution. Don't swim around boat docks with electrical outlets or house boats plugged into shore power. That's what killed those 3 kids this summer swimming between house boats.

jmsokol
08-17-2012, 03:01 PM
In all of the discussion of possible causes of hot trailer skins, we know we don't want this to happen, but if it DOES happen. won't a GFCI at the connection point detect the imbalance of current flow in ANY of these situations if a shock occurs and cut the power, thus stopping the electroshock accident??? GFCI's are only on the 20 amp pedestal outlet, not on the 30 or 50 amp outlets since there's too much stray leakage current that will cause random tripping (and your fridge going off). Also remember that if you're plugged into a RPBG (Reverse Polarity Bootleg Ground) outlet, that the current flow isn't detected by the GFCI circuity and won't trip. Even if it DOES trip for some other reason, it won't disconnect the hot ground from your shore power connection, creating a hot-skin condition where all the circuit breakers turned off. See http://www.noshockzone.org/rv-electrical-safety-part-viii-gfci/ for an article I wrote about GFCI theory.

Interesting, isn't it?

Mike

jimtoo
08-17-2012, 03:58 PM
Mike,

I have a Gardner Bender (GVD-3505) Live Wire Tester (http://www.homedepot.com/buy/gardner-bender-12-600-vac-adjustable-circuit-alert-non-contact-voltage-tester-341798.html). I purchased it a while back when someone else suggested using this to trace wiring without contact. I have found that it works really good. No contact is needed, you can check the plug and anything from 12v to 600v AC.
What is your opinion on this for someone to carry and use to check the campground box or connector? I know it would not be something to carry after hookup and going swimming,, but to check things before and after the initial setup.

Jim M

Wish the OP would come back and answer my questions so we could know a little more about when and how.

jmsokol
08-17-2012, 04:18 PM
The Gardner Bender (GVD-3505) Live Wire Tester (http://www.homedepot.com/buy/gardner-bender-12-600-vac-adjustable-circuit-alert-non-contact-voltage-tester-341798.html) should do the job as well, as long as you know where to slide the sensitivity switch so that it doesn't trigger on everything. Usually the 12-volt setting is too sensitive for testing outlet polarity before plugging in, but the lowest threshold (highest sensitivity) is good for checking hot-skin conditions. Remember, according to National Electrical Code, there should be no more than 3 volts between the earth ground and the chassis/skin of your RV. In reality, it should be much lower than that if you have a solid low-impedance connection back to earth, but there could be induced voltage drops caused by other RV pedestals around the campgrounds. Any more than a few volts is cause for concern. So your 5 volt test should be pretty spot on. Note that I've not personally used the GB tester you mention, so I can only guess at its actual voltage thresholds. But I would be glad to do a calibrated test if someone at Gardner Bender would send me a sample.

Don't think that I'm fishing for a free tester because I can't afford one. I have dozens of them on my test bench already. But I'm always willing to talk to manufacturers about their products.

Mike

evolvingpowercat
08-17-2012, 04:29 PM
FYI, the kind I bought at Ace Hardware today was a Sperry Instruments VD6505, there were cheaper ones on the wall too but I liked seeing all the certifications on the packaging that were not on the cheaper ones.

http://www.acehardware.com/product/http%3A//ACE.imageg.net/graphics/product_images/pACE3-3638256enh-z6.jpg

jmsokol
08-17-2012, 07:30 PM
FYI, the kind I bought at Ace Hardware today was a Sperry Instruments VD6505, there were cheaper ones on the wall too but I liked seeing all the certifications on the packaging that were not on the cheaper ones.


Looks like a good choice. I'm sure you know this, but for many of the non-technical members on this forum, it's generally not a good idea to go cheap with test gear, especially if it's going to be used around high-voltage or high-current situations. Really well built test gear will survive all sorts of voltage spikes and such, but cheap gear has a tendency to blow up in your hands on occasion. There's something call an Arc-Flash which is more terrifying than being knocked unconscious by a big shock. I won't go into it here, but that's why you see electricians at power sub-stations running around in what appear to be space suits.

Mike Sokol

porthole
08-17-2012, 09:12 PM
So, Mike, glad you came back on forum with this. I was out all day and had planned on linking the previous thread where you went over all this in the same depth.

Those original posts hit home as several years ago I leaned on our dog pen at camp and got zapped. No wonder the pups were not jumping that weekend. We disconnected and left.

After your last series, I orderd up the Fluke Volt alert and use it every time, thanks!

For those looking for the Fluke tester, it s readily available on eBay or amazon. Got mine for $21 delivered.



Closest thing I know of to test for the presence of A/C voltage without touching it is this thing. We use it whenever we need to determine if a wire is energized. Also use it to determine the charged area around a downed line on the ground or if a vehicle hits a pole and wires are draped on it. These run around $300, though.

http://www.hotstickusa.com/products/achs/ACHotStick_DataSheet_English.pdf

Hey John, we use a special tool also.
When the lineman holds both ends in each hand, I figure it is safe to approach.

JohnDar
08-17-2012, 09:47 PM
So, Mike, glad you came back on forum with this. I was out all day and had planned on linking the previous thread where you went over all this in the same depth.

Those original posts hit home as several years ago I leaned on our dog pen at camp and got zapped. No wonder the pups were not jumping that weekend. We disconnected and left.

After your last series, I orderd up the Fluke Volt alert and use it every time, thanks!

For those looking for the Fluke tester, it s readily available on eBay or amazon. Got mine for $21 delivered.




Hey John, we use a special tool also.
When the lineman holds both ends in each hand, I figure it is safe to approach.

Do the blue sparks between his teeth indicate not so safe?

jmsokol
08-17-2012, 10:41 PM
Everybody....

Thanks for all your input so far. I learn a lot about the state of the RV industry by trolling these forums. As you can see, I have a lot of time and knowledge invested in understanding and writing about electrical safety. But I'm working on a nationwide teaching program that I hope to get a training grant for that will fund these efforts. So I need your help with spreading the knowledge that RV electrical safety is serious business, and that everyone needs to take charge of their own safety. Please send a link to this thread to anybody you know with an RV and let them know you plan to observe these basic safety principals. And go ahead and tell your Heartland rep and dealer that you would like to see more training for both the public and RV technicians on how to test RVs and their power sources for voltage, grounding and hot-skin conditions.

I'm only one guy doing this as a side gig (yes, I have full time job as a technical writer and seminar instructor for music mixing), so it's hard for me to spend as much time as needed to teach everybody. That's why I only show up on specific forums occasionally. Once I'm done here for now, I'll find another interesting thread somewhere else that needs my help and work on that for a day or two, and so on... However, with proper industry and grant support I could really attack the problem of improperly wired campgrounds and RVs and save a lot of lives.

Thanks very much for your support, and keep those comments and questions coming. :cool:

Mike Sokol
mike@noshockzone.org
www.noshockzone.org (http://www.noshockzone.org)

jbeletti
08-17-2012, 10:59 PM
Sadly, this product doens't exist. I'll be glad to talk to Progressive or any other manfacturer at the Hershey RV show next month. Just give me a heads-up.

Mike Sokol
mike@noshockzone.org

Mike - will you have a booth?

jimtoo
08-17-2012, 11:10 PM
I know our RV's are put to a test or supposed to be made to meet certain specifications, which is good and for our protection. Now if the RV parks could be subjected to a ,, maybe inspection each year to make sure things are maintained correctly. I think it would eliminate a lot of burned fuses, microwaves, TV's and other electrical problems and serious accidents. Just a thought... I know we would end up paying more for camping... but .. how much is a life worth.

Electricity is nothing to mess with, you can't see it, you can't hear it and when you feel it,,,,, it's usually to late.

Jim M

jmsokol
08-18-2012, 05:38 AM
Mike - will you have a booth?
No, but I'll be doing a guest appearance with Gary Bunzer (the RV Doctor) and will be presenting a short hot-skin demonstration (small scale) during his AC electricity class on Thursday. I could also do a full-scale hot-skin demonstration during the day if there's room for it and a RV to use. As you all can imagine it's a pretty dangerous stunt, so I'll only do it in a roped off area or enclosed shop.

I'll also be around the Hershey show all day kicking tires and hanging out with Chuck Woodbury (RVtravel.com) and Gary B.

jmsokol
08-18-2012, 05:50 AM
I know our RV's are put to a test or supposed to be made to meet certain specifications, which is good and for our protection. Now if the RV parks could be subjected to a ,, maybe inspection each year to make sure things are maintained correctly. I think it would eliminate a lot of burned fuses, microwaves, TV's and other electrical problems and serious accidents. Just a thought... I know we would end up paying more for camping... but .. how much is a life worth.

Electricity is nothing to mess with, you can't see it, you can't hear it and when you feel it,,,,, it's usually to late.

Jim M
I agree... and have pitched the idea of RV park electrical inspections to a lot of park organizations and franchises, but nobody wants me to look at their pedestals. They're afraid I'm going to find something wrong that would cost money to fix. I do have a pretty robust test that should take less than 5 minutes per pedestal to complete (maybe less). So if there's 200 campsites in an RV park that's basically 10 hours of work to check the entire park if you're moving it. I'm not sure how much a certified RV tech or retired Master Electrician costs per hour ($25 to $50 off book, maybe) so that's a minimum of $250 to $500 for an inspection once a year. Smaller RV parks could be done in half a day. You could amortize that inspection cost over the rentals all year, and it would add less than a dollar per day to your camping day-rate (a lot less in most instances).

rick_debbie_gallant
08-18-2012, 08:23 AM
I agree... and have pitched the idea of RV park electrical inspections to a lot of park organizations and franchises, but nobody wants me to look at their pedestals. They're afraid I'm going to find something wrong that would cost money to fix. I do have a pretty robust test that should take less than 5 minutes per pedestal to complete (maybe less). So if there's 200 campsites in an RV park that's basically 10 hours of work to check the entire park if you're moving it. I'm not sure how much a certified RV tech or retired Master Electrician costs per hour ($25 to $50 off book, maybe) so that's a minimum of $250 to $500 for an inspection once a year. Smaller RV parks could be done in half a day. You could amortize that inspection cost over the rentals all year, and it would add less than a dollar per day to your camping day-rate (a lot less in most instances).

I am very surprised that A: the parks liability insurance does not require it. B: The local code enforcement agency does not require it. C: The state does not require it. I am talking about some sort of electrical certification. And while I am at it, make sure the sanitary system is up to par as well as the fresh water source.

Yes I am sure it would increase the cost of staying at a given place, but what is a life or lives worth? Just my nickles worth.

jbeletti
08-18-2012, 08:39 AM
No, but I'll be doing a guest appearance with Gary Bunzer (the RV Doctor) and will be presenting a short hot-skin demonstration (small scale) during his AC electricity class on Thursday. I could also do a full-scale hot-skin demonstration during the day if there's room for it and a RV to use. As you all can imagine it's a pretty dangerous stunt, so I'll only do it in a roped off area or enclosed shop.

I'll also be around the Hershey show all day kicking tires and hanging out with Chuck Woodbury (RVtravel.com) and Gary B.

Mike,

Gary B is cool, so I am sure you are too :)

I'll plan to sit in on your presentation. Replied to your email with my contact into. I'll be at the show all week.

wdk450
08-18-2012, 04:08 PM
Sorry to keep adding to the pile of posts on this thread, but two ideas occurred to me. First of all, we should establish some period of time to proactively change out the RV water heater element - Maybe every 5 years? An electrical test to see if they are electrically leaky is a little involved, and a visual inspection might miss the tiny pinholes that can cause electrical current leakage. This scheduled replacement is not as important in a home electric water heater, because its wiring is permanent and fixed.

The second idea is that this electrical leakage hazard cannot exist if there is no hot electric power to the water heater. Specifically keep the red water heater switch turned off unless you really need it. Think about just making hot water with propane.

evolvingpowercat
08-18-2012, 08:43 PM
Who knows, there may be hundreds or thousands of RV hot water heaters with electric heating elements that have the pin hole failures that can cause electricty to be in contact with the water in the tank. If the RV is connected to a good ground one would never know it was occurring as the current flow thru the water would never be enough to trip the hot water heater non-GFCI type circuit breaker. There might be some minor voltage on the RV metal body parts due to some voltage rise due to the resistance of the saftey ground path to the power panel where neutral and saftey ground were bonded and tied to earth ground but it likely would not even be enough to trigger a non-contact voltage tester.

I think only a camper disconnected from all AC power resistance measurement from the heating element terminals to ground would indicate that the hot water heating element insulation to water had failed. I am sure there is some manufacturer's spec that it should read "higher than X" if all is good.

All the more reason that RV electric hot water heaters should have GFCI protection built into them like the AC hot water heaters in hot tubs have to have.

wdk450
08-18-2012, 10:16 PM
I think only a camper disconnected from all AC power resistance measurement from the heating element terminals to ground would indicate that the hot water heating element insulation to water had failed. I am sure there is some manufacturer's spec that it should read "higher than X" if all is good.



Actually there is a piece of test equipment that is used at every hospital, and is available to electrical equipment manufacturers. It is called an Electrical Safety Tester. The U.S. version is for 110 Volt A.C., 20 amp maximum line cord equipments. The tester has an outlet into which the device to be tested is plugged in, and a single wire testing cable with a clip connector. The clip connector is connected to a device under test's external grounded point, either a metal chassis point, or a ground post specifically for this testing. By manipulating the switches on the tester you can read the resistance of the device's power cord ground circuit to the test outlet, open the ground circuit going to the test outlet and simultaneously read the leakage current present on the now ungrounded equipment case. You can do these tests with both a normally wired (hot and neutral) and reverse wired testing outlet (to simulate the device being plugged into a reverse wired wall outlet).

We used this same tester in a different configuration along with some saline solution in a basin to check TransEsophogeal Ultrasound probes (put down the throat) for the same sort of pinholes like those in water heater elements that could cause excessive electrical leakage. BTW the fail spec for this leakage used at a point within the body near the heart is 20/100000 of an ampere. (20uA) We are currently talking here about external shock currents of about 5 milliamperes - about 250 times as much.


The ultrasound probes were usually damaged by patients biting them. Repair/replacement was $10,000 and up, each.

jmsokol
08-20-2012, 05:56 AM
Sorry to keep adding to the pile of posts on this thread, but two ideas occurred to me. First of all, we should establish some period of time to proactively change out the RV water heater element - Maybe every 5 years? An electrical test to see if they are electrically leaky is a little involved, and a visual inspection might miss the tiny pinholes that can cause electrical current leakage. This scheduled replacement is not as important in a home electric water heater, because its wiring is permanent and fixed.

The second idea is that this electrical leakage hazard cannot exist if there is no hot electric power to the water heater. Specifically keep the red water heater switch turned off unless you really need it. Think about just making hot water with propane.
You're tending to fixate on the hot-water heater failure, when that's not the real issue here. The primary problem is that the RV has obviously lost its safety ground bonding thru the power outlet. This allows the RV's chassis and body to float to whatever voltage ANY appliance connected to its electrical system will create. So if the safety-ground bond is broken, either from corroded/loose bonding screw in the RV's panel, a broken ground wire in the shore power cable/pigtail/dog-bone, or a loose/corroded/missing safety-ground wire in the power outlet it's plugged into, then replacing the water heater element pro-actively is like putting a band-aid on a bullet wound without removing the lead. If you don't have a continuous, low-impedance ground-fault path back to the campground's or house's service panel grounding-bond point, then the next time your microwave, toaster oven, fridge, stereo system, battery inverter/charger (anything, really) develops an internal electrical leakage with a fault-to-ground, your RV's chassis/skin will once again rise to 60 or 120 volts and present a shock hazard to anybody touching it.

If you have a properly grounded/bonded RV (via its shore power connection, NOT a ground rod driven in the earth next to it), then it should be impossible for any internal leakage failure of the RV's appliances or electrical system to create a hot-skin condition. Just can't happen.

Of course, GFCI's are supposed to detect fault currents that result from a person touching an energized object while "earthing" it, but remember at campgrounds GFCI's are typically only required on the 20 amp service, NOT the 30 and 50 amp services. That's means the pedestal won't offer you any active hot-skin safety on the 30/50 outlet. It only creates a passive ground/bond system that will drain away any currents created by appliance failure. Break that passive ground/bond connection FOR ANY REASON and you're now playing Russian Roulette the next time any appliance has an internal hot-to-chassis wiring condition from heat, vibration, or a wire pinched under a bolt. Since you can't replace and test the entire RV's electrical system and appliance every few years, then you're depending on the safety ground/bond to protect your life.

This is exactly how the electrical code was designed and written, and if it's followed then you should always be safe when touching your RV. But if you violate the code with non-existent safety grounds in your shore power outlet (the original OP's problem, I would guess) then you're risking the lives of your family and friends who touch your RV.

I'm sorry if this sounds like something nobody wants to worry about or that it seems too complicated, but when you plug your RV into ANYTHING, you personally become a junior electrician of sorts, and need to verify that the voltage and grounding is correct. Yes, if the campground's electrician (or the DIY guy who wired your garage outlet) did it correctly, and your shore power cords and adapters are regularly inspected and maintained, it shouldn't be an issue. But it only takes that 1 in a 1,000 chance to create the right conditions for an RV hot-skin. You can stretch those odds in your favor by visibly inspecting and quickly testing outlets for grounds and incorrect voltages before you plug in, and knowing that your should NEVER feel a shock from your RV. Electrical knowledge is power.

Much more on this later after the Hershey show. :cool:

jmsokol
08-20-2012, 06:21 AM
Actually there is a piece of test equipment that is used at every hospital, and is available to electrical equipment manufacturers. It is called an Electrical Safety Tester.
Yup, I actually have four different testers for my grounding experiments. Originally called a GLIT (Ground Loop Impedance Tester) my first Circuit Tester from the 70's was made by a UK company called Woodhead. I now also have an Ideal SureTest, an Amprobe INSP-3, and an Extech CT-70 on my test bench. These are all in the $200 to $300 range and do a good job of testing for ground continuity (low impedance) but all can be fooled by an RPBG outlet (read my description of testing for an RPBG earlier in this thread).

The quickest and simplest way to detect an RV hot-skin condition is by using a NCVT (Non Contact Voltage Tester) as I've described earlier. It's safe, quick, and should detect 99% of all RV hot-skin conditions. See picture below. Yes, your RV might be a little bigger, but this is my Class B- example. :)

And while a Surge/Voltage protector on your RV will protect you from MANY or even MOST electrical failure conditions, it simply can't protect you from ALL failure conditions, especially a reflected hot-skin condition. If that occurs a Surge/Voltage protector will disconnect you from the pedestal circuit breakers, but your RV skin could still be electrified from another RV's hot-skin condition on the same campground loop as you. Of course, if the RV campground's pedestals are properly wired and bonded to the incoming safety-ground/neutral point, you will NEVER develop a reflected hot-skin condition. Separate ground rods at each campsite are not only next to useless, they're a violation of the National Electrical Code if not double-bonded back to the service entrance ground/bond point.

Staying safe around electricity takes personal training and safety awareness.

jmsokol
08-21-2012, 09:01 AM
If any of you will be at the Hershey RV show next month, I'll be making a guest appearance with Gary Bunzer (the RV Doctor) at his AC voltage seminar on Saturday Sept 15th where I'll be demonstrating hot-skin testing. I'll also be hanging around the show all day kicking tires, so if you see my name badge (Mike Sokol) give me a shout. :cool:

jmsokol
08-29-2012, 05:56 PM
No, but I'll be doing a guest appearance with Gary Bunzer (the RV Doctor) and will be presenting a short hot-skin demonstration (small scale) during his AC electricity class on Thursday. I could also do a full-scale hot-skin demonstration during the day if there's room for it and a RV to use. As you all can imagine it's a pretty dangerous stunt, so I'll only do it in a roped off area or enclosed shop.

I'll also be around the Hershey show all day kicking tires and hanging out with Chuck Woodbury (RVtravel.com) and Gary B.

My day at the Hershey RV show with Gary Bunzer has changed to Saturday. I'll be doing a No~Shock~Zone presentation sometime during his 5 PM to 7 PM time slot on AC power.

Are any of you going to be there? If so, say hello if you see me. :D

jbeletti
08-29-2012, 09:07 PM
My day at the Hershey RV show with Gary Bunzer has changed to Saturday. I'll be doing a No~Shock~Zone presentation sometime during his 5 PM to 7 PM time slot on AC power.

Are any of you going to be there? If so, say hello if you see me. :D


Sorry to hear your slot changed. Do Show attendees stay that late for seminars?

jmsokol
08-29-2012, 09:20 PM
I'll be around the Hershey show all day on Saturday, and Gary B. says the Saturday seminars are the best attended. However, if anybody else has a booth at the show and would like me to do a 15 minute No~Shock~Zone demonstration sometime during the day, send me a PM.

jmsokol
08-31-2012, 04:04 PM
I'll be around the Hershey show all day on Saturday, and Gary B. says the Saturday seminars are the best attended. However, if anybody else has a booth at the show and would like me to do a 15 minute No~Shock~Zone demonstration sometime during the day, send me a PM. I see there was another electrocution death in the news. This happened to a women who jumped into an irrigation ditch shile trying to save a dog being shocked by bad irrigation pump wiring. Then the two men who tried to save her were electrocuted and died as well. http://msn.foxsports.com/other/story/3-electrocuted-in-idaho-ditch%3B-1-tried-to-save-dog

I'm thinking about adding a pet electrical safety module to my No~Shock~Zone seminar since there's been a lot of pet deaths from hot-skin shocks recently.