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#184569 - 02/13/09 01:53 PM Grounding electrode from inside subpanel??  
sparkync  Offline
Member 		Joined: Oct 2002
Posts: 828
NC
I recently changed a service from 100 amps to 200 amps. The inside panel had a ground wire going to the water pipe. This panel is not located with the mains outside. Can I leave this ground wire hooked up or do I disconnect it? I have the grounding electrode outside connectected to the Main panel outside. Thanks... Steve

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#184574 - 02/13/09 02:10 PM Re: Grounding electrode from inside subpanel?? [Re: sparkync]  
frenchelectrican  Offline
Member 		Joined: Feb 2003
Posts: 939
Wi/ Paris France { France for ...
For myself I will leave it and that panel become a subpanel so as long you have grouding bar in there and keep the netrual and ground seprated and the exsting EGC is there you can use it.

{ unless your local code say something diffrent then follow thier regualtions }

Merci,Marc

Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

#184575 - 02/13/09 02:11 PM Re: Grounding electrode from inside subpanel?? [Re: sparkync]  
leland  Offline
Member 		Joined: Aug 2007
Posts: 853
Lowell area, Ma. USA
Metal main water pipe?
What is your main ground electrode now?
Either way, the copper water pipe must be bonded.

sounds like your ok, bond the pipe to the Subs ground.Jump the meter so you have a good bond on the house side.

250.52 addresses this.

Last edited by leland; 02/13/09 02:13 PM. Reason: water meter jumper

#184580 - 02/13/09 06:04 PM Re: Grounding electrode from inside subpanel?? [Re: sparkync]  
KJay  Offline
Member 		Joined: Nov 2007
Posts: 763
MA, USA
Originally Posted by sparkync
I recently changed a service from 100 amps to 200 amps. The inside panel had a ground wire going to the water pipe. This panel is not located with the mains outside. Can I leave this ground wire hooked up or do I disconnect it? I have the grounding electrode outside connectected to the Main panel outside. Thanks... Steve


I think the problem might be that if it was previously 100A, then that bond to the water piping is probably only a #6 or #8 Cu.
With a 200A, it now should be at least #4, according to Table 250.66.
I would remove the old wire and run a new #4 Cu from the piping to the main panel outside. IMO, that's where it really belongs anyway.

#184581 - 02/13/09 08:10 PM Re: Grounding electrode from inside subpanel?? [Re: KJay]  
leland  Offline
Member 		Joined: Aug 2007
Posts: 853
Lowell area, Ma. USA
K-Jay- hello.

At this point providing he met the proper GEC methods. Isn't this just now a bond?

#184585 - 02/13/09 09:31 PM Re: Grounding electrode from inside subpanel?? [Re: leland]  
Yoopersup  Offline
Member 		Joined: Mar 2003
Posts: 830
Michigan
Kjay is Right your grounding electroid wire at the outside 100 is probally 6 or 8.
You need a #4 for 200 amps . (250.66)
This MUST be run to the Service disconnecting means outside Not subpanel. (250.24C).
Also read (250.50)250.52)
Yoopersup

#184586 - 02/13/09 10:01 PM Re: Grounding electrode from inside subpanel?? [Re: Yoopersup]  
leland  Offline
Member 		Joined: Aug 2007
Posts: 853
Lowell area, Ma. USA
If the water main is primary, then a supplemental GE is needed.
My understanding is He has his ground (thru rods) met.Now the water need only be bonded.

#184587 - 02/13/09 10:33 PM Re: Grounding electrode from inside subpanel?? [Re: leland]  
Yoopersup  Offline
Member 		Joined: Mar 2003
Posts: 830
Michigan
250.50
ALL grounding electrodes as described in 250.52(a)1 though (a)6 that are PRESENT. shall be bonded TOGETHER to form grounding electrod system.
See 250.52 Water Underground Water pipeing.
Your only bonding the water line when less then 10ft of metal pipe is outside the building.
Again read code sections I refered to in my ist post.
Yoopersup
If its part of the Grounding Electrod system it must go to the Service disconnect or disconnect switches.

#184588 - 02/13/09 10:55 PM Re: Grounding electrode from inside subpanel?? [Re: Yoopersup]  
leland  Offline
Member 		Joined: Aug 2007
Posts: 853
Lowell area, Ma. USA
Originally Posted by Yoopersup
250.50
ALL grounding electrodes as described in 250.52(a)1 though (a)6 that are PRESENT. shall be bonded TOGETHER to form grounding electrod system.
See 250.52 Water Underground Water pipeing.
Your only bonding the water line when less then 10ft of metal pipe is outside the building.
Again read code sections I refered to in my ist post.
Yoopersup
If its part of the Grounding Electrod system it must go to the Service disconnect or disconnect switches.


Got Me Guy!!!
"..That are present...."
Up size it and bring that conductor back to the main.

Thanx for grabbing my attention to that.I got tunnel vision.

#184592 - 02/13/09 11:27 PM Re: Grounding electrode from inside subpanel?? [Re: Yoopersup]  
renosteinke  Offline
Cat Servant
Member 		Joined: Jan 2005
Posts: 5,316
Blue Collar Country
Look at 250.66 closer ... the text, not the table. You need not have a GEC larger than #6, no matter the service size.

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