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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => AC Power and Grounding => Topic started by: Mike Sokol on April 09, 2018, 09:59:32 PM
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This is a picture from last week at a campground that was recently upgraded with new pedestals. Apparently, there were no ground wires run, so the contractor came up with this solution. I can't go into details yet, but once I get to the bottom of things I'll be able to discuss it fully here. Comments or captions welcome...
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"If water tap is hot, contact office."
Presuming they did that at every pedestal... wow. This must be somewhere without required inspections. The kludge violates Code, too. Raises so many questions.
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Even if a ground wire were run, typically you would "re establish" a ground. This is not acceptable ( by the NEC) as an alternative to a grounding wire but that was already in the OP.
Self drilling sheet metal screw is not acceptable- must have 2 threads engaged. Hose clamp is not a listed ground clamp. Finally, does anyone think that wire will survive even half this camping season? Maybe we want to protect it somehow?
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Maybe this is a great opportunity to put in a ground rod at every pedestal and have independent grounds for everyone. That'll at least remove the chance of a reflected hot skin problem. I think I got that term right. :)
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"If water tap is hot, contact office."
Presuming they did that at every pedestal... wow. This must be somewhere without required inspections. The kludge violates Code, too. Raises so many questions.
On the plus side, at least there's a drip loop.
Toodleoo!
Ron Hebbard.
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Presuming they did that at every pedestal... wow. This must be somewhere without required inspections. The kludge violates Code, too. Raises so many questions.
Apparently this was just done at 100 campsites where they poured new concrete pads and installed new pedestal boxes. One of my readers had an Intelligent Surge Protector that monitors voltages and ground, plugged his RV shore power cordeset into this pedestal and got an open-ground alarm light. He called the campground maintenance guy who told him to bypass his Surge Protector and not worry about it since they always wire them like that.
I'm doing a full article on this situation so I can't write any more details here until the story clears. I'm sure there's going to be even more revelations once I interview all the parties involved.
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I don't get it. All that money for pads and new pedestals and such an obvious and simple FUBAR. What is it with these campgrounds? Do they all use the same incompetent electrician?
Can't be money - what would be the extra cost per pedestal for a ground wire? Lazy doesn't really explain it either. And the owner putting up with the shoddy work?
I don't get it.
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That looks like my laundry room....
Probably not an acceptable bond to the water pipe, they sell fancy bond clamps for that. (http://www.a1components.com/Images/products/medium/SEN1001.jpg)
Running new wires could get spensive....
JR
PS: Of course the million ohm question is there any pex or plastic plumbing involved.
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That looks like my laundry room....
Probably not an acceptable bond to the water pipe, they sell fancy bond clamps for that. (http://www.a1components.com/Images/products/medium/SEN1001.jpg)
Running new wires could get spensive....
JR
PS: Of course the million ohm question is there any pex or plastic plumbing involved.
My guess is YES. I'm sure the cheapest materials and methods were used, based on the way the electrical work was done.
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PS: Of course the million ohm question is there any pex or plastic plumbing involved.
I think they reused the existing underground wiring and just poured new pads and hung new pedestals. But I have very little information just yet. But I know it's an error x100.
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Forgive my ineptness with NEC.
But would grounding to the pipe actually help at all?
Or ground rods, or nearly anything other than a dedicated ground wire?
My understanding is grounds can become dangerous if there isn't a dedicated ground wire in the system and grounding to pipes is only permissible when using ALL metal pipes which is highly unlikely these days (basically its for grandfathered piping systems).
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I think they reused the existing underground wiring and just poured new pads and hung new pedestals. But I have very little information just yet. But I know it's an error x100.
Ugly, but use of GFCI outlets in the pedestals will provide a modicum of human safety.
JR
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If it's an all metal water pipe system camp-ground wide, it will be a lot better grounding system than ground rods. But it has to be done correctly.
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If it's an all metal water pipe system camp-ground wide, it will be a lot better grounding system than ground rods. But it has to be done correctly.
But if the copper isn't bonded to neutral (like due to some plastic plumbing), a fault energizing that floating ground at one pedestal, could energize the floating ground at all the other pedestals (like my old kitchen wiring).
JR
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But if the copper isn't bonded to neutral (like due to some plastic plumbing)............................
JR
That's the problem with metal pipe ground systems. As time goes by, more and more plastic finds its way into the system. In my old suburb, they are replacing the metal main pipes with plastic, a few streets at a time. I don't know what they do about grounding the individual homes that only have water pipe grounds.
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Work like that is why I use these. I always meter everything before connecting but you never know what’s wrong down the line or will be tomorrow!
(https://uploads.tapatalk-cdn.com/20180410/e874f2e59f2a71515249d1b6618c40e4.jpg)
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Mike, great catch.
I hope you get published before someone dies.
I would think the maker of the pedestals would want it fixed before they get caught up in lawsuits.
I hope the campground is closed. If not I hope a camper calls the state AHJ.
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That's the problem with metal pipe ground systems. As time goes by, more and more plastic finds its way into the system. In my old suburb, they are replacing the metal main pipes with plastic, a few streets at a time. I don't know what they do about grounding the individual homes that only have water pipe grounds.
If there's metal pipes interconnecting these pedestal "grounds" in an area, but a section of the mail feeder pipe was changed to plastic, then a hot-to-chassis short in one of the RVs could energize all the other RVs in that section, as well as electrify the water from any spigot in that section. Seems like a very dangerous situation to me that shouldn't be allowed.
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If there's metal pipes interconnecting these pedestal "grounds" in an area, but a section of the mail feeder pipe was changed to plastic, then a hot-to-chassis short in one of the RVs could energize all the other RVs in that section, as well as electrify the water from any spigot in that section. Seems like a very dangerous situation to me that shouldn't be allowed.
+1... GFCI outlets and forget the copper plumbing ground will probably do less harm to humans, and be affordable.
JR
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If the pipes are metal and accessible, they should be at least bonded to the Safety Ground at each pedestal. If there is 10 feet or more, metal pipe in the earth, they serve the same function as a ground rod.
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+1... GFCI outlets and forget the copper plumbing ground will probably do less harm to humans, and be affordable.
JR
The camp ground is too cheap to install a grounding system, I don't think that they will go for GFCI breakers or receptacles.
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If the pipes are metal and accessible, they should be at least bonded to the Safety Ground at each pedestal. If there is 10 feet or more, metal pipe in the earth, they serve the same function as a ground rod.
Yes, the same function as a ground rod, which is a lightning strike earth path. But not the same functions as an EGC connected back the the service panel's Neutral-Ground Bonding point, which is the fault path that quickly trips the breakers if there's a hot-to-chassis short.
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+1... GFCI outlets and forget the copper plumbing ground will probably do less harm to humans, and be affordable.
JR
Are GFCI outlets available for all of the types of outlets that are found in an RV park? There could be three or more different voltage/amperage outlets at each parking space.
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Are GFCI outlets available for all of the types of outlets that are found in an RV park? There could be three or more different voltage/amperage outlets at each parking space.
Gfci for the bigger amperage outlets will be expensive.
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Are GFCI outlets available for all of the types of outlets that are found in an RV park? There could be three or more different voltage/amperage outlets at each parking space.
There's 3 different receptacles in a campground pedestal. The 20-amp outlet is required by code to be a GFCI. The 30-amp outlet is sometimes GFCI protected at state campgrounds. And I've heard of a few places that are installing a GFCI breaker on the 50-amp/120-240-volt outlet. But the problem of additive leakage currents is a real issue with the GFCI being this far upstream.
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Gfci for the bigger amperage outlets will be expensive.
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Yes perhaps, but how expensive is pulling new wire from the service panel?
If already GFCI just lose the Rube Goldberg screw clamp ground to the copper plumbing that could do more harm than good.. Even if not GFCI I see no reason to keep the faux "safety" ground.
JR
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If already GFCI just lose the Rube Goldberg screw clamp ground to the copper plumbing that could do more harm than good.. Even if not GFCI I see no reason to keep the faux "safety" ground.
There's no GFCIs on the 30 or 50 amp receptacles in this particular campground. Only the 20-amp receptacle has a GFCI and NOBODY uses that for an RV.
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There's no GFCIs on the 30 or 50 amp receptacles in this particular campground. Only the 20-amp receptacle has a GFCI and NOBODY uses that for an RV.
Maybe pulling new wire isn't more expensive.
JR
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Maybe pulling new wire isn't more expensive.
JR
Doing the right thing is almost always less expensive than a wrongful death lawsuit.
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Doing the right thing is almost always less expensive than a wrongful death lawsuit.
Amen, brother!
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Doing the right thing is almost always less expensive than a wrongful death lawsuit.
Yes always true in hindsight. When cash is tight people try to do just enough to get by.
The thrust of this thread is that the faux safety ground is not only not safe, but perhaps even more dangerous than floating.
First do less harm if you can't do no harm.
Not a trivial issue.. A gfci/rcd on the entire service might help but the accumulated leakage threshold would have to be high.
The park owner might be able to charge more for a handful of premium parking spots outfitted with GFCI outlets, or not. ::)
JR
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Doing the right thing is almost always less expensive than a wrongful death lawsuit.
Unless it's a Ford Pinto (https://auto.howstuffworks.com/1971-1980-ford-pinto12.htm).
Exploding Pintos would make a great band name. Apparently, I'm not the first one to think of it (https://www.facebook.com/explodingpintos/).
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Today while riding my bike, my brain kept working on this problem and came up with this....
"if" the copper plumbing is continuous and provides a low Z electrical path
"and if" that copper plumbing is routed anywhere near the mains service panel.
The copper plumbing could be properly bonded to neutral at the service panel. Then it could be used as a safety ground conductor for the outlets. They would still have to replace those screw hose clamps with proper pipe clamps, but that would be cheaper and at least provide a proper safety ground. Not exactly ideal but betta...(probably not even redneck code).
I would at least use RCD/GFCI breakers at the service again not ideal but betta.
JR
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"if" the copper plumbing is continuous and provides a low Z electrical path
"and if" that copper plumbing is routed anywhere near the mains service panel.
"And if" that galvanized steel standpipe is properly connected to the copper piping with a dielectric union, all bets are off.
Unless, of course, the underground piping is galvanized steel, which is a distinct possibility.
There's so many ASSumptions here we're gonna need a stable.
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"And if" that galvanized steel standpipe is properly connected to the copper piping with a dielectric union, all bets are off.
Unless, of course, the underground piping is galvanized steel, which is a distinct possibility.
The impedance of the plumbing conductor is not ideal or even a long term solution, but probably better than what is in place now for safety ground (i.e. dirt).
There's so many ASSumptions here we're gonna need a stable.
I am just trying to help come up with a cost effective (albeit temporary) solution. Nobody expects plumbing to remain a low electrical impedance long term with the popularity of using plastic pipe for repairs but it is possible to empirically measure the impedance of the plumbing in place, here and now.
JR
PS: I haven't made any assumptions yet... human safety is too important to rely upon assumptions. "If-then" is not an ASSumption. I was the one who first posted my speculation about possible plastic pipe use in the plumbing.
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So from the POV of a licensed electrician that has done "retrofit" wiring like this and had it inspected by an inspector...
Often the 3 wire existing system is allowed to be reused provided that you install a grounding electrode and treat this as a service-so the ground and neutral would be bonded at each pedestal.
Additionally, all grounding electrodes have to be connected-this metal pipe would be viewed as a grounding electrode, so it would need to be connected to the grounding system-but given the uncertain nature of metallic plumbing these days with future repairs, you still would be required to drive 2 8' ground rods at least 6 ft apart.
If the water pipe does indeed provide a continuous path, there is the potential for multiple ground/neutral bonds-but the hazard from this in an outdoor situation is minimal compared to hazard of different potentials on metal objects.
As of the 2017 NEC, all single phase outdoor receptacles less than 100 amps are required to be GFCI protected.
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So from the POV of a licensed electrician that has done "retrofit" wiring like this and had it inspected by an inspector...
Often the 3 wire existing system is allowed to be reused provided that you install a grounding electrode and treat this as a service-so the ground and neutral would be bonded at each pedestal.
Additionally, all grounding electrodes have to be connected-this metal pipe would be viewed as a grounding electrode, so it would need to be connected to the grounding system-but given the uncertain nature of metallic plumbing these days with future repairs, you still would be required to drive 2 8' ground rods at least 6 ft apart.
If the water pipe does indeed provide a continuous path, there is the potential for multiple ground/neutral bonds-but the hazard from this in an outdoor situation is minimal compared to hazard of different potentials on metal objects.
As of the 2017 NEC, all single phase outdoor receptacles less than 100 amps are required to be GFCI protected.
I think I saw a listing for a wireless transmitter/ receiver for grounds on eBay
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So from the POV of a licensed electrician that has done "retrofit" wiring like this and had it inspected by an inspector...
Often the 3 wire existing system is allowed to be reused provided that you install a grounding electrode and treat this as a service-so the ground and neutral would be bonded at each pedestal.
Additionally, all grounding electrodes have to be connected-this metal pipe would be viewed as a grounding electrode, so it would need to be connected to the grounding system-but given the uncertain nature of metallic plumbing these days with future repairs, you still would be required to drive 2 8' ground rods at least 6 ft apart.
If the water pipe does indeed provide a continuous path, there is the potential for multiple ground/neutral bonds-but the hazard from this in an outdoor situation is minimal compared to hazard of different potentials on metal objects.
As of the 2017 NEC, all single phase outdoor receptacles less than 100 amps are required to be GFCI protected.
Depending on the location of this RV park, it is possible that the work was done without a building permit or inspection(s). Pure speculation on my part, but such things happen here and presumably elsewhere, too.
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I get that. It is also possible that the NEC isn't even law where this install is done-unless an authority having jurisdiction passes a law/ordinance incorporating it, it isn't law anyway. At the end of the day, be alert and aware to protect you and yours. Shoddy work may leave them open to a lawsuit-but I am sure you'd rather have your family member than the cash.
I am just saying that from the standpoint of the inspectors I have worked with (in Iowa, most of that time the rules that are enforced are the NEC as written) it would be acceptable to leave the existing (assumption) 3 wire feeders, drive 2 ground rods and tie them together with #6 Cu to the pedestal and using a listed (like the one pictured above) clamp bond the water pipe to the system, then bond the neutral to the ground so that any short will trip the breaker.
Don't confuse acceptable with being good. Code is the minimum acceptable standard. It would still be better to go back and add the fourth wire for a ground. My preference would be to use bare #6 so that you would have even better contact with "earth".
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It is sad that this is so common in RV parks given that a RV connected to power has inherent risks already that are not present in a fixed building. Metal skin touched all the time including every time you open the door. sitting on rubber tires. Wiring subject to vibration.
Mike Sokol seems to be taking the best possible route toward solving the problem.
1. Educate the RV owners them selves to know what is safe, know how to test for it, know how to protect them selves from sketchy hook ups and know that it is important for them to point out problems.
2. Push RV parks to put in good electrical service.
Bottom line. Your safety is your responsibility.
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It is sad that this is so common in RV parks given that a RV connected to power has inherent risks already that are not present in a fixed building. Metal skin touched all the time including every time you open the door. sitting on rubber tires. Wiring subject to vibration.
Mike Sokol seems to be taking the best possible route toward solving the problem.
1. Educate the RV owners them selves to know what is safe, know how to test for it, know how to protect them selves from sketchy hook ups and know that it is important for them to point out problems.
2. Push RV parks to put in good electrical service.
Bottom line. Your safety is your responsibility.
One of the client reps I work with just sold his RV park. He told me electrical service and plumbing were his biggest problems, both from a park maintenance standpoint and the "crap some folks bring into the park." I'm pretty sure he's had 'reflected hot skin' grounding problems with client camping units. I don't want to envision the plumbing issues... ;)
Specifically addressing point #2 - non-compliant businesses are either ignorant or willfully disregarding life safety issues. Ignorance can be educated but willful disregard requires the Big Stick of law and regulation enforcement.
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It seems to me that a GFCI device in the RV power inlet should be equally protective. Any current leaking from a hot skin condition should trip and disconnect.
Only an energized ground that is not part of the GFCI (line-neutral) current loop could remain unprotected.
JR
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Specifically addressing point #2 - non-compliant businesses are either ignorant or willfully disregarding life safety issues. Ignorance can be educated but willful disregard requires the Big Stick of law and regulation enforcement.
Giving the Big Stick to others can cause a lot of harm.
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Giving the Big Stick to others can cause a lot of harm.
Non compliance with life safety issues kills people. That's a fair bit o' harm, eh?
If folks instinctively and inherently did the "right thing" we wouldn't need the types and amounts of regulations we tend to see. People operate in their own very narrow self interests and most often the financial aspect is the primary interest.
I once worked for a boss whose idea of workplace safety was to admonish workers to 'be more careful.' When he broke his leg on the loading dock (he got it between the dock and trailer) we told him to be more careful... after we'd previously mentioned safety barriers, markings and training. Until it happened to him, it wasn't worth the money... now there are safety chains, marked aisles and a posted dock safety notice at this workplace.
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Non compliance with life safety issues kills people. That's a fair bit o' harm, eh?
Yes That is a lot of harm. There are many examples of governments using big sticks to enforce regulations that get people killed.