Separate structure grounding

[realolman]

Does installing a grounding electrode at a separate structure according to 250.32, become 2 because of 250.56?

 

[Dennis Alwon]

Does installing a grounding electrode at a seperate structure according to 250.32, become 2 because of 250.56?

Imo, yes it does. Two rods or a cee

 

[iwire]

Imo, yes it does. Two rods or a cee

I agree, 250.32(A) sends us to 250.50.

 

[M. D.]

Imo, yes it does. Two rods or a cee

Well this past weekend I took my 15 hr code seminar here in mass and they, the two of them,.. said absolutely one is all that is required. The last shed I did I drove two probably will the next time as well.

But When I looked it does say

"shall have a grounding electrode or grounding electrode system"

When none are present I am sent to 250.50 and there I'm told to pick one from a list ,.. I know all about 250.56 but nothing sends us there ,.. that was the reasoning any way and they were quite sure of themselves if you know what I mean ,.. I wonder if it was the same folks Bob had at his seminar

 

[M. D.]

I also found this 2007 ROP it was accepted I looked in the ROC could find no comments at all , but it did not make the final draft ,.. so does anyone know what happened ?? (grey was proposed to be removed blue he wanted to revise)

____________________________________________________________
5-120 Log #1298 NEC-P05 Final Action: Accept
(250.32(A))
____________________________________________________________
Submitter: Joseph Whitt, JW Electric

Recommendation: Revise text to read:

250.32 Buildings or Structures Supplied by Feeder(s) or Branch Circuit(s).
(A) Grounding Electrode. Building(s) or structure(s) supplied by feeder(s) or
branch circuit(s) shall have a grounding electrode or grounding electrode
system installed in accordance with 250.50 Part III of 250 . The grounding
electrode conductor(s) shall be connected in accordance with 250.32(B) or (C).

Where there is no existing grounding electrode, the grounding electrode(s)
required in 250.50 shall be installed.
Substantiation: As now worded, 250.32(A) only states that this grounding
electrode is required to conform to the provisions of 250.50 and nowhere in
250.50 does it refer to 250.53(D) nor 250.56.
As an instructor of both electrical contractors and inspectors in the state of
North Carolina, the most asked questions on grounding are about 250.32(A).
The questions I am always asked are:
What are the requirements for the grounding electrode system at a building or
structure fed by a feeder? If a water pipe that is in contact with the earth for
more than ten feet and then it is connected to a nonmetallic pipe is used as the
grounding electrode is it required to conform with 250.53(D)?
If a ground pipe or rod is used as the electrode, is it required to conform to
250.56?

By adding that 250.32(A) must comply to Part III of 250 would be all
encompassing and include the supplementary addition of another electrode
outlined in 250.53(D)(2) and the resistance to ground of a rod, pipe, or plate
found in 250.56. There would be conformity to the grounding electrode system
between a feeder that supplies another building or structure and at a service.

Panel Meeting Action: Accept

Number Eligible to Vote: 15

Ballot Results: Affirmative: 15

 

[augie47]

Not that my opinion matters, but I don't know that I can agree with the seminar gurus. While it's true that you are only referenced to 250.50, it would seem the other pertinent articles can not be ignored. If we choose not to address 250.56 can we then not also ignore 250.53(G) and not drive them 8 ft in the ground, or ignore 250.53(B) and use a rod covered in paint ?

 

[M. D.]

Not that my opinion matters, but I don't know that I can agree with the seminar gurus. While it's true that you are only referenced to 250.50, it would seem the other pertinent articles can not be ignored. If we choose not to address 250.56 can we then not also ignore 250.53(G) and not drive them 8 ft in the ground, or ignore 250.53(B) and use a rod covered in paint ?

I here what you are saying and I tend towards agreeing , but why then , do they bother to spell it out for us in regard to suplemental electrodes when water pipe is involved? 250.53(D)(2)

 

[augie47]

Humm ! ROP, ROC time........

 

[M. D.]

I did look,.. there was another attempt to add the "Part III" language for the 2005,.. it was proposed like this (blue new,..grey proposed removal)

Recommendation:
Revise the title and Section 250.32 as follows:
250.32 Two or More Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s) from a Common Service.

(A) Grounding Electrode. Where two or more buildings or structures are supplied from a common ac service by a feeder(s) or
branch circuit(s), the grounding electrode(s) required in Part III of this article at each building or structure shall be connected in
the manner specified in 250.32(B) or (C). Where there are no existing grounding electrodes, the grounding electrode(s) required in
Part III of this article shall be installed.

It turned into this after they accepted it in principle ,.. So that's twice they removed the part III wording ,. they did say that this met his intent

Panel Meeting Action: Accept in Principle

Revise 250.32 title and 250.32(A) to read as follows:

250.32 Buildings or Structures Supplied by Feeder(s) or Branch Circuit(s)
.
(A) Grounding Electrode. Building(s) or structure(s) supplied by feeder(s) or branch circuit(s) shall have a grounding electrode or
grounding electrode system installed in accordance with 250.50. The grounding electrode conductor(s) shall be connected in accordance
with 250.32(B) or (C). Where there is no existing grounding electrode, the grounding electrode(s) required in 250.50 shall be installed.

Exception: A grounding electrode shall not be required where only a single branch circuit supplies the building or structure and the
branch circuit includes an equipment bonding conductor for grounding the conductive non-current-carrying parts of equipment. For
the purpose of this section, a multiwire branch circuit shall be considered as a single branch circuit.

 

[George Stolz]

I'm confused. Looking at the language in 250.32, I'm required to look at "Part III" not 250.50 anymore. So what's the problem?

 

[M. D.]

Well I'd say that there are a least 5 of us ,.. Me being the most confused of the lot.. the other four,.. the two guys at the seminar ,.. Gus,. and that is probably all my fault ,.though he has not stated he is confused, trust me, he is and you ,.. Who is mostly just being polite . I did not have my book this morning and was shooting from memory.Sorry for confusing every one

perhaps I should email the seminar provider that ROP

Again,. I'm sorry,.. and a bit embarrassed as well.

 

[augie47]

I'm confused. Looking at the language in 250.32, I'm required to look at "Part III" not 250.50 anymore. So what's the problem?

Part of the confusion might be that the "Part III " is a change in'08 from "250.50" in '05