ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 255 guests, and 16 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 2 of 2 1 2
Joined: May 2002
Posts: 1,716
R
Member
Makokiller, can you give an NEC reference to where it is required to have a #4 to the rod or rods?

Might you be thinking about a local code?

Roger

Joined: Dec 2004
Posts: 51
M
Member
look at the chart 250.66 he said that he has a 200amp service.. do the math

Joined: Jan 2003
Posts: 4,391
I
Moderator
Mako take a look at 250.66(A) and do the reading. [Linked Image]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: May 2002
Posts: 1,716
R
Member
Mako, as with any part of the NEC you must read the whole article, you can not stop at one section or table.

Quote
250.66 Size of Alternating-Current Grounding Electrode Conductor
The size of the grounding electrode conductor of a grounded or ungrounded ac system shall not be less than given in Table 250.66, except as permitted in 250.66(A) through (C).

Here is the kicker.

Quote
250.66(A) Connections to Rod, Pipe, or Plate Electrodes Where the grounding electrode conductor is connected to rod, pipe, or plate electrodes as permitted in 250.52(A)(5) or (A)(6), that portion of the conductor that is the sole connection to the grounding electrode shall not be required to be larger than 6 AWG copper wire or 4 AWG aluminum wire.


Roger

Joined: Dec 2004
Posts: 51
M
Member
so let me get this straight.. you could use #6 copper for your city water pipe connection, and your ground rods??? even for lets say a 300amp service??

Joined: Jan 2003
Posts: 4,391
I
Moderator
Quote
so let me get this straight.. you could use #6 copper for your city water pipe connection, and your ground rods??? even for lets say a 300amp service??

To the rod yes, to the water line it would be sized directly from table 250.66.

Put a 4000 amp service in a field and you will only need a 6 AWG CU to one or two ground rods.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Dec 2004
Posts: 51
M
Member
now that is what i thought.. when do 300 amp services, I run #4 to the rod and #2 to the water meter, and thanks, with the price of copper nowadays it will save me some money..

Joined: May 2002
Posts: 1,716
R
Member
Mako, as Iwire points out, which is the point of this thread, the connection to the rod(s) only need be a #6 copper regardless of the size of the service.

In this thread the water piping is not part of the GES.

Roger

Joined: May 2002
Posts: 1,716
R
Member
Mako, sorry, you posted while I was typing.

Roger

Joined: Apr 2003
Posts: 13
B
Member
I think you need to bond the water line ( Key Word ) and ground 2 rods

Page 2 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5