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Author Topic: Ground this....  (Read 11866 times)

John Roberts {JR}

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Re: Ground this....
« Reply #30 on: April 11, 2018, 02:40:58 PM »

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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Jonathan Johnson

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Re: Ground this....
« Reply #31 on: April 11, 2018, 03:47:53 PM »

Doing the right thing is almost always less expensive than a wrongful death lawsuit.

Unless it's a Ford Pinto.

Exploding Pintos would make a great band name. Apparently, I'm not the first one to think of it.
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John Roberts {JR}

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Re: Ground this....
« Reply #32 on: April 11, 2018, 04:10:15 PM »

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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Jonathan Johnson

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Re: Ground this....
« Reply #33 on: April 11, 2018, 04:45:27 PM »

"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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John Roberts {JR}

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Re: Ground this....
« Reply #34 on: April 11, 2018, 07:25:34 PM »

"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).
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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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Stephen Swaffer

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Re: Ground this....
« Reply #35 on: April 11, 2018, 07:45:06 PM »

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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Jay Barracato

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Re: Ground this....
« Reply #36 on: April 11, 2018, 07:53:41 PM »

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

Sent from my Moto Z (2) using Tapatalk

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Mark Cadwallader

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Re: Ground this....
« Reply #37 on: April 11, 2018, 10:12:38 PM »

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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Stephen Swaffer

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Re: Ground this....
« Reply #38 on: April 11, 2018, 10:54:44 PM »

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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Frank DeWitt

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Re: Ground this....
« Reply #39 on: April 12, 2018, 10:00:37 AM »

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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Re: Ground this....
« Reply #39 on: April 12, 2018, 10:00:37 AM »


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