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Grounding for electrical system (Removing copper water lines)

Grounding for electrical system (Removing copper water lines)

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  #1  
Old 02-06-19, 06:49 AM
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Grounding for electrical system (Removing copper water lines)

I am replacing all copper pipe in my existing house with new PEX pipe with the exception of a few short pieces that connect to fixture on the floor above. After taking some time and checking all branches for fitting I'll need, etc, I found that my existing copper has a clamp like thing on it with 2 ground wires attached. Looks like 1 ground wire comes from outside and attaches to clamp and the other goes from clamp to the panel box. Then there is another ground that goes from outside, straight to the panel box. I believe this one was recently installed when my electric was transitioned from overhead to underground. Is it safe to remove the ground from my copper pipe and just leave it connected within clamp so its continuous from outside to the panel box?

I do know when the underground service was installed, I was told that a 2nd ground rod was installed at that time.

also, where the copper line originates inside my basement from the outside main line there is about a 6" section of pipe, then a water meter, and then I plan to start my pex pipe from there. There is currently a ground wire connecting the copper on both sides of the water meter. Is this safe to remove since I'm removing all copper on one side of the meter?

thanks
 
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  #2  
Old 02-06-19, 08:39 AM
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If you are not replacing the metal line coming into the house then you need to leave the ground attached to metal pipe entering the house.
If the line entering the house is not metal then you should already have two ground rods outside and water line connection can be removed.
If you are removing the metal water line entering the house then you need to have two ground rods for the electrical system. You may need to add one because with a metal water line only one additional rod is required.
 
  #3  
Old 02-06-19, 09:07 AM
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Where the copper pipe comes into my home, it immediately goes into a water meter box. On the other end of eater meter box, I'm running all new pex and removing the copper. The ground at the water meter only goes from the supply side of it to the house side of it and is clamped on. Doesnt appear to be connected to anything else. If I remove the copper pipes on house side, there will be nothing ground wise attached to the foot or so of copper on supply side of water valve. At the end of my house supply line (where it terminates) is where the ground wire comes in from outside and is clamped on to water line and then continued to panel box. The second ground wire comes from outside and straight to panel box. Little confused by your post Joed. I'm definantly not an expert on this. Does that short section where the pipe first enters my home really need to be grounded? My grounding rods and panel box are on the opposite side of the house at end of water supply run.
 
  #4  
Old 02-06-19, 09:08 AM
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also, where the copper line originates inside my basement from the outside main line there is about a 6" section of pipe, then a water meter, and then I plan to start my pex pipe from there. There is currently a ground wire connecting the copper on both sides of the water meter. Is this safe to remove since I'm removing all copper on one side of the meter?

You will need a new Grounding Electrode Conductor (ground wire) from the neutral bus in the panel to within 5 feet of where the water line enters the house. You should remove the existing jumper around the meter, but leave the water pipe clamps in place. The new GEC (ground wire) should in one length from the panel, jump around the meter and be terminated in both of the existing water pipe clamps. If you have a 100 amp service you can use either #6 copper or #4 aluminum bare stranded ground wire or for a 200 amp service you can use either #4 copper or #2 bare stranded ground wire.

I have to ask though out of my own curiosity, why are you replacing the copper water lines? Copper is Cadillac over pex.
 
  #5  
Old 02-06-19, 09:37 AM
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My house was built in the 50s and have heard that copper pipes can become an issue when they get old, as mine are. I am running new PEX pipe supply lines to my new addition and figured I would replace the copper while I was at it with the pex for addition work.

you said to leave both clamps, therefore I would have to reset the clamp onto my pex pipe after installed? I plan to connect pex straight to the water meter box if i can. Have to figure out how to connect to the water meter. I have a picture of it saved on my phone as well. So with my current setup I can remove the copper and install pex. Only thing I need to do is run a 4 guage wire from neutral bar to the 1' section of pipe where it enters my house as copper?

Good to remove the other ground clamp attached to water line at end of supply run also?
 
  #6  
Old 02-06-19, 10:30 AM
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Nowadays the correct grounding electrode conductor runs from the main water line before the meter. In your case you have about eleven inches worth of eligible length of pipe to clamp the GEC to.

That short section is the most important part to be bonded to the house electrical ground (to become part of the grounding electrode system).

Your previous setup with the clamp after the meter may have sufficed in thge past and grandfathered but is now moot because all the copper on that side is/will be replaced.with plastic.

Where do the ground wires going outside go to?

The up to date code also calls for a #6 copper GEC from the panel to two ground rods at least 6 feet apart. You may or may not already have these. These will suffice even if you replace the remaining foot of copper coming in from the wall to be plastic.

If the pipe clamp is also a terminal strip to attach other wires to, it could hang loose if the pipe was replaced with plastic. It could also be fastened to the plastic pipe for physical support.

Poke around in the dirt where you see a wire half buried or emerging, to see where the wire goes. It is not unusual for a ground rod to be completely covered.
 

Last edited by AllanJ; 02-06-19 at 10:52 AM.
  #7  
Old 02-06-19, 10:47 AM
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Nowadays the correct grounding electrode conductor runs from the main water line within 5' of where it exits the foundation undeground and before the meter. In your case you have about eleven inches worth of eligible length of pipe to clamp the GEC to.
so I need to run this GEC to the foot of copper where it enter my basement and clamp it? Other end of GEC connected in panel box?

Where do the ground wires going outside go to?
Assuming the one that was there when I purchased the house goes to the original ground rod. The other wire that goes straight to panel box would have been attached to the ground rod installed when my electric service was run underground I would assume.

The up to date code also calls for a #6 copper GEC from the panel to two ground rods at least 6 feet apart. You may or may not already have these. These will suffice even if you replace the remaining foot of copper coming in from the wall to be plastic.
It was stated previously that for 200 amp service, a #4 GEC was required, is that correct or can I use #6? I have a 200 amp service.

If the pipe clamp is also a terminal strip to attach other wires to, it could hang loose if the pipe was replaced with plastic. It could also be fastened to the plastic pipe for physical support.
the pipe clamp has 2 GEC connected to it by one clamp. It's like a brass color clamp.
 
  #8  
Old 02-06-19, 06:39 PM
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you said to leave both clamps, therefore I would have to reset the clamp onto my pex pipe after installed? I plan to connect pex straight to the water meter box if i can.

Maybe I misunderstood. If after the meter the pex will connect right at the meter you can eliminate the clamp after the meter and run the GEC to the clamp before the meter.


so I need to run this GEC to the foot of copper where it enter my basement and clamp it? Other end of GEC connected in panel box?

Yes, in the panel the GEC terminates on the neutral bus.


It was stated previously that for 200 amp service, a #4 GEC was required, is that correct or can I use #6? I have a 200 amp service.

#4 copper GEC for 200 amp service to the water line within 5 feet of where it enters the house (or #2 aluminum), but only #6 copper GEC from panel neutral bus to ground rod. You never need a GEC to ground rod larger than a #6 copper.


the pipe clamp has 2 GEC connected to it by one clamp. It's like a brass color clamp.

Not sure what you mean by this. You only need one GEC to the water service water pipe clamp. Or........do you mean the ground rod clamp?
 
  #9  
Old 02-07-19, 07:34 AM
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Where do the ground wires going outside go to?
You cannot assume. You have to find out. This is the only way the problem can be solved with a minimum of new components added.

As things stand now with all the unknowns, your punch list has two ground rods on it.
 

Last edited by AllanJ; 02-07-19 at 07:54 AM.
  #10  
Old 02-07-19, 08:02 AM
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The simple answer is leave the ground as it is. Removing the copper inside the house does not affect the grounding system.
 
  #11  
Old 02-08-19, 03:46 PM
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I found the top of 1 ground rod with wire attached that runs into basement and straight to my panel box. Then there is a ground wire that runs from my panel to the copper water line which also has a ground from telephone company service box tied to water line with it. The other ground wire is just a jumper and goes from where water pipe first enters foundation and jumps past water meter and is attached to copper pipe on other side. Unless I’m missing something, those are all the grounds I could find. Appears my system was grounded to water line for 50+ years until I moved in and had my electric service run underground (approx. 2 years ago) which at that time a ground rod was installed and run to panel box. With all this said, what do I need to do to remove this copper piping back to water meter?

Edit after further review - I found a 2nd ground rod which has the wire running from it to the other ground rod and then over to the main panel box.

Do I only need a 4 Gauge ground wire from before water meter to my panel box or is there more?
 

Last edited by Jrk5230; 02-08-19 at 04:54 PM. Reason: Found 2 ground rod
  #12  
Old 02-08-19, 06:12 PM
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Which copper pipe are you removing next?
 
  #13  
Old 02-08-19, 06:12 PM
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The ground system you describe is exactly what needs to be there. You do not need to do anything as a result of changing the internal lines to pex.
 
  #14  
Old 02-08-19, 08:00 PM
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Nothing needs done with the 1' section of copper where it enters my foundation into basement? The remainder of pipe from the 1' section on will be PEX pipe as I'm replacing all copper line back to 1' from where it enters my basement.

Safe to remove ground wire from panel box and water line? Talking about the one that goes from panel box to water line and has the Verizon telephone service box connected to it. I believe its safe to remove since panel is grounded to the 2 ground rods outside. Although, the Verizon service box outside house would not be grounded anymore, or should I just clamp it on to the ground wire in basement that comes from ground rods?
 
  #15  
Old 02-08-19, 08:08 PM
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Leave the water line ground in place. It is the primary ground for.your system.
 
  #16  
Old 02-08-19, 10:08 PM
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Confused my Pcboss's response. The system is grounded by (2) 10' ground rods and I want to use that as the primary ground and remove the copper pipes for replacement by PEX. The only part of water line I'm asking if it needs grounded is the 1' piece where it enters my foundation wall basement.
 
  #17  
Old 02-09-19, 05:21 AM
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You can remove the interior copper water lines. The metallic water line from the street will still be the primary grounding. The interior piping is not part of your grounding system since the connection was ahead of the meter. It was simply bonded to the grounding system.

There is no need to connect any grounding conductors to the PEX. Plastic is non-conductive.
 
  #18  
Old 02-09-19, 05:43 AM
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The water line coming into the house MUST be connected to the grounding system.
Leave everything as it is. Do NOT remove the connections to the water line entering the house.
 
  #19  
Old 02-09-19, 06:25 AM
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When removing the "front" clamp from the copper pipe to be removed and replaced from the house side of the meter, do not cut any of the ground wires immediately. Rejoin any wire ends that came loose using the loose clamp as a terminal strip if suitable and needed. Except that any wire end that goes nowhere or that duplicates the path of some other wire may be cut off at a later date if you don't find any use for it.

Later (nitpicking) ...

If the ground wire from the panel to the one foot section of copper pipe behind the water meter remaining has a splice (that you could take apart) in it or is thinner than #4 gauge then replace it, using a continuous run of #4 gauge copper. This wire may continue unbroken to the ground rods if you needed to replace the wire mentioned in the next paragraph and it was easiest to do it that way.

If the ground wire from the panel to the ground rods is thinner than #6 gauge or has a splice before the first ground rod then it should be replaced, with a run of #6 or fatter, continuous at least as far as the first ground rod.
 

Last edited by AllanJ; 02-09-19 at 07:26 AM.
  #20  
Old 02-09-19, 09:01 AM
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Everyone is saying to leave the first 1' water line as is.. and others are saying the 1' section must act as a ground as well as the ground rods already installed. Confused because the 1' section currently just has a jumper ground wire from one incoming from street side of water meter to house side of water meter. That's it. Doesnt connect to panel box or to a ground rod. So I'm getting mixed signals to leave it as is and others saying it must be main ground for system.

on a side note, my water meter inside basement wall has a small wire running outside my house, is this some kind of ground as well or not?


Here's exactly what I have in case there is some confusion. Am I good to remove the copper line after the water meter? And do I need to install a #4 ground from water from street 1' piece over to main panel box? Is it safe to not have this done for a few days after new PEX is installed?
[IMG][/IMG]
 

Last edited by Jrk5230; 02-09-19 at 09:36 AM.
  #21  
Old 02-09-19, 10:24 AM
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on a side note, my water meter inside basement wall has a small wire running outside my house, is this some kind of ground as well or not?
That is to a small button on the side of your house for the meter reader to read the meter electronically and not need to come inside your house.

Confused because the 1' section currently just has a jumper ground wire from one incoming from street side of water meter to house side of water meter
That is so that if the water meter is removed there is still continuity between copper pipes.

The 1 foot section as you are calling it really 20 or 30 feet of cooper in the ground out to the water main. That is required to be used as the ground.

If your drawing is correct the grounding wire did not go from the panel to the meter. If that is true then you must a add a cable to connect to the section of pipe coming in from the street.
 
  #22  
Old 02-09-19, 10:29 AM
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But do I still need to run the 4 guage ground from 1'stub to main panel ground bar? You say dont make changes but if I remove my copper pipes, it will change as that jumper wouldnt connect to the pex for continuity and the copper on house side wouldnt be there anymore.
 
  #23  
Old 02-09-19, 10:32 AM
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Sorry I edited my post while you were responding.

The original setup should have run the cable to entry point of the water line. I misunderstood your current setup. I thought the cable from the panel ran to the water meter and then jumpered it. That is how is should have been done.
You need to run that cable now from the panel to the pipe entry point.
 

Last edited by joed; 02-09-19 at 11:55 AM.
  #24  
Old 02-09-19, 11:02 AM
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But do I still need to run the 4 guage ground from 1'stub to main panel ground bar?

Yes, read post #8 again. ................
 
  #25  
Old 02-09-19, 12:08 PM
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Ok now it makes sense. I thought there was some confusion and that's why I posted the quick drawing I made to show where they run to. I'm removing my copper today so the 1'stub will not be grounded until Monday. Is that an issue to leave that way for a couple days?
 
  #26  
Old 02-09-19, 08:22 PM
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Can you verify that the small wire from the water meter and going outside actually goes to some box or gadget outside that might be a sensor for meter reading?

A few days delay in completing the needed wiring will not do any harm.

You need the #4 wire from the panel neutral bar to the 1 foot copper pipe behind the water meter whether or not you replaced any other copper pipe with plastic.

The short jumper across the water meter connected to nothing else besides the pipes over there may be eliminated completely after the pipe on the house side of the meter has been replaced with plastic.

The wiring going from the panel to to the telephone equipment needs to stay intact and it may have splices. With the copper pipe gone it does not have to be clamped to any pipe. As originally installed it properly grounded the cold water plumbing to the electrical panel and electrical system ground but did not sufficiently ground the electrical panel to the water line at the latter's entry point.
 

Last edited by AllanJ; 02-09-19 at 08:42 PM.
  #27  
Old 02-09-19, 10:48 PM
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Can you verify that the small wire from the water meter and going outside actually goes to some box or gadget outside that might be a sensor for meter reading?

I have checked it and it contains a red and black wire that goes outside for the water company to easily read meter.



On a side note, I came across another Verizon phone line service box inside my basement. Therefore, I have the one mentioned previously in this post which is located outside on siding, and this one I found today that is inside my basement between floor joists. The box outside has the cat wire and the ground wire. Ground goes to the water line as previously mentioned and that jumps over to the main panel from one clamp. The cat wire runs from first Verizon box into the second Verizon box and then splits off to my first story where my phone is. This second box also had a ground wire attached to my water line which I removed today during removal of the copper lines. Does it also need a ground or does the ground to the first box cover both?
 
  #28  
Old 02-10-19, 05:06 AM
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My confusion was i thought the conductor went from the panel to both sides of the meter. I did not understand that the piping was acting as the conductor between the connection near the panel and the jumper at the meter. Your drawing cleared that up.
 
  #29  
Old 02-10-19, 06:05 AM
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The second Verizon box should have a ground wire. This ground wire can be attached anywhere along the ground wire going from the panel to the first Verizon box or anywhere along the #4 ground wire to the one foot water pipe you are going to install in a few days, if it does not first reach the panel.

Connecting a ground wire from something to the nearest water pipe and connecting a ground wire from the panel to the nearest water pipe is not considered sufficient grounding for the "something" even if both wires are connected to the same section of pipe.
 
  #30  
Old 02-10-19, 06:12 AM
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Ok thanks, my 4 GA will run within a few feet of that 2nd verizon box so I'll connect it then.

I was also debating on removing that box. Doesnt make sense to have two and I want to put a media closet of my own in soon.
 
  #31  
Old 02-10-19, 08:36 PM
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All of my copper water lines have been removed and replaced with PEX pipe. Ready to move on to ground the 1' copper stub where it enters my basement. Is 4 guage soft drawn copper good for grounding the 1' stub of pipe? Planning to run it near exterior walls of basement along floor joists above.
 

Last edited by Jrk5230; 02-10-19 at 10:06 PM.
  #32  
Old 02-11-19, 07:04 AM
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Any kind of #4 copper wire can be used -- soft drawn, oxygenated, stranded, solid, bare, tempered, insulated, etc. as available.
 
  #33  
Old 02-11-19, 09:02 AM
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Can I run the 4 gauge back to my new sub panel and attach it to the ground bar or does it have to run back to main panel? Just a thought since there is #8 ground between my main panel and sub panel. Then from main panel out to ground rods. See post #20 picture for visualization.
 
  #34  
Old 02-11-19, 03:12 PM
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Run the #4 ground wire to the neutral bar in the first panel in or on the building (the main panel here).
 
  #35  
Old 02-11-19, 06:55 PM
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Is 4 guage soft drawn copper good for grounding the 1' stub of pipe?

I like #4 bare stranded ground wire.
 
  #36  
Old 02-15-19, 09:00 PM
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After removing the cover to my main panel I found that the ground wire coming from the outside ground rods is bonded to the panel box on the inside. It isn't under a screw on the neutral bar. Is this ok or should it be attached to neutral bar? I will be running a ground wire to this main panel from my 1' copper pipe where it enters my basement as well.
 
  #37  
Old 02-16-19, 04:19 AM
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Can you post a picture of the connection inside the panel?
 
  #38  
Old 02-16-19, 09:07 AM
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I will post the picture when I get home. On a side note, I cannot figure out a way to add a photo from my cell phone gallery. Is there a way to do this without transferring picture to email and doing it on a desktop?
 
  #39  
Old 02-16-19, 12:26 PM
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I found that the ground wire coming from the outside ground rods is bonded to the panel box on the inside. It isn't under a screw on the neutral bar. Is this ok or should it be attached to neutral bar?

Common mistake, it should be on the neutral bus since this is the main panel.
 
  #40  
Old 02-16-19, 10:05 PM
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Sorry for the picture being sideways. Anyways, here is where my two ground rods outside are connected to main panel. Maybe the inspector at the time this was hooked up allowed it because my system was still grounded to water line as well at that time. It currently is not. Since I'm going to run a new 4 gauge ground wire from copper water line stub pipe where enters basement over to the neutral bar on main panel, can I leave this connection the way it is in that case or do they both have to run to neutral ground bar?

 

Last edited by Jrk5230; Yesterday at 12:25 AM.
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