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Main service panel is grounded to outside grounding rod and to inside water pipe

Main service panel is grounded to outside grounding rod and to inside water pipe

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  #1  
Old 04-03-15, 03:40 AM
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Main service panel is grounded to outside grounding rod and to inside water pipe

Hello. The person who installed the service panel in our house (unknown) grounded the panel via the right ground bar to an outside grounding rod. They used the left ground/neutral bar to make a 20 foot run of copper ground wire to a cold water pipe. From the point that they made this ground the pipe continues 20-30 feet and then there is the water meter. From the water meter the pipe continues another 20 feet and goes through a "mouse-hole" in the wall and finally into the ground. So we're talking about 20 feet of ground wire to a cold water pipe, 20 feet to the meter, then 20 feet til it goes underground. Now as I understand it you should ground to a cold water pipe if the ground point is within 5-10 feet of where the pipe goes under ground, otherwise you don't.

Does anyone have any suggestions regarding how I should proceed? I really don't know if the meter actually has continuity in this situation or not. Any ideas or suggestion would be very much appreciated.Name:  IMAG0019.jpg
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  #2  
Old 04-03-15, 04:36 AM
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I have seen it grounded outside. Someone who knows the code better that I do will be here soon.
 
  #3  
Old 04-03-15, 06:32 AM
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I assume this is existing work of unknown age? The description sounds pretty reasonable for something done a couple decades ago -- not quite to modern standard, but no glaring problems. The only improvement I would really recommend is putting pipe clamps on either side of the meter and jumping the ground around it to ensure continuity. If you wanted to go to modern standard, the grounding electrode conductor (copper wire from panel to water pipe) should be unbroken from the panel to a point no more than 5' from where the water pipe enters the house. There should also be jumpers around any potentially non-conductive interruptions in the metal piping system like meter, filters, water heater, etc. It would not be required for you to do any of these upgrades unless you're also replacing the main service panel.
 
  #4  
Old 04-03-15, 08:03 AM
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It is true that if A is bonded to B then B is bonded to A. It is true that if A is bonded to B and B is bonded to C then A is bonded to C.

That said, the existing fat ground wire attached to the water pipe 50 or so feet from where the water pipe exits the house functions as a bonding jumper (required by the most up to date code) from the plumbing system to the electrical ground but does not qualify as a grounding electrode conductor from the panel to the water pipe exiting underground.

Using an approved crimp type clamp, you could splice onto the existing fat wire almost at the existing pipe clamp and extend to where the pipe exits the foundation, making a qualifying grounding electrode conductor back to the panel. With the old pipe clamp still in place, this new piece will also properly jump the meter although some inspectors want to see a shorter jumper right at the meter. For a 200 amp service both wires would have to be at least #4 gauge. Sometimes #6 can be used; I don't have the sizing table from the NEC handy.

If the property has a metal water pipe exiting and then running underground for at least 10 feet (not proven otherwise) then a GEC to one such water pipe is needed regardless of the distance from the panel.
 

Last edited by AllanJ; 04-03-15 at 08:44 AM.
  #5  
Old 04-03-15, 11:58 AM
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I done see any reason to make any changes. This sounds like the accepted practice from years ago. There is little advantage to make any changes.
 
  #6  
Old 04-03-15, 12:29 PM
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My house was built in 1987 and it has a #4 copper conductor going from the panel to the water line serving an outside faucet just a few feet away. It also has a #4 copper going to a ground rod that is somewhere near underground conduit where the power comes into the meter, maybe two ground rods, I don't know and I have never seen the rods, just the wire going into the earth.

Some day I will run a #4 from the panel to the point where the copper water pipe enters my garage, some forty feet or so from the panel around the perimeter of the garage from the panel; someday, but only because I already have the wire.
 
  #7  
Old 04-03-15, 08:09 PM
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I think I'd leave the existing water pipe grounding as it is, but add a jumper around the meter using #4 copper.
 
  #8  
Old 04-06-15, 08:53 PM
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Fantastic responses.

Thank you to everyone who replied to this thread. I have to admit that I was skeptical, but everyone has been quite sensible and decent. Usually you run into a lot of smart remarks and "degraders", but I am pleasantly surprised and encouraged by all of the very well informed answers that I've recieved. Now if I can keep my smarty pants to a bearable state then we should all be happy campers. Thanks everyone, your the best. I believe that I will actually place short jumpers around anything that may not have continuity and also extend this ground to the point where it enters the wall and goes into the ground. I'm one of those types who are ground crazy, I'll ground washing machines and anything with a green screw... The trick is getting it to ground to the main rod that the main service is grounded to... I don't want any different potentials or extra line noise caused by my grounding obsesssion, so its important for me to ground everything to the main grounding rod and if there are any grounds exisiting around the house that aren't "bonded" to the main ground then that is something that has to be made to happen... (I noticed that the telephone company has grounded the telephone line at the service box to a separate ground that is isolated all by itself and I have to somehow get it grounded to the main rod, the whole way around the house (60 yards is a lot of wire)....
 
  #9  
Old 04-07-15, 04:59 AM
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The washing machine is properly bonded to the electrical ground if it has a 3 prong plug and the receptacle is properly grounded.

Otherwise you can connect a separate ground wire. This must reach the panel or reach a grounding electrode conductor to your ground rod or reach the fat wire that went from the panel to your water pipe clamp provided that an extension of that wire has been completed to within 5' of where the pipe exits the house.

There are other possibilities such as connecting to metal plumbing, that might achieve adequate grounding but that are not technically correct.
 

Last edited by AllanJ; 04-07-15 at 05:41 AM.
  #10  
Old 04-07-15, 07:33 AM
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its important for me to ground everything to the main grounding rod and if there are any grounds exisiting around the house that aren't "bonded" to the main ground then that is something that has to be made to happen
This is exactly what the intersystem bonding bridge is for.

http://www.amazon.com/Arlington-GB5-.../dp/B00422M1K4
 
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