EGC wire and metal boxes

[quogueelectric]

Quog, the point of the thread isn't production, or reasons why it should be done or why not.

I have seen several folks who indicated they believed it was mandatory, in my original scenario, that the EGC wire be connected to the box, inside the box, with a jumper wire. I just wanted some discussion to see whether it really was mandatory, or if people had just read it and wrong, possibly put meaning in it that wasn't there.

As for your question of where it would be done, what if we just ran the EGC wire from the panel and wanted it terminated at an air compressor. I don't have to put a bonding jumper at the boxes in between if the EMT and fittings are listed for grounding.

No you are not wrong However I know many excelent electricians who have been taught to put in a ground tail at all jboxes as a good job. Is it the minimum code compliant NO however if you told them they couldnt ground those already grounded boxes they would hate you and they would actually install the equipment faster if they didnt have to think about ground or no ground. You are 100% right it is not necessary I dont understand why you need to persue this. Is it to stick it to an inspector or to force people who are used to doing something a certain way to do it your way. When I first started as a foreman 25 years ago I used to force my men to make 12 to 10 wire splices with yellow wirenuts because it was within code and I had thousands of them to do. Save the boss a couple hundred more bucks. Being the foreman I won the battle but lost the war. I was right however I made so many enemys by forcing them to work against thier grain it wasnt worth the grief. They are still complaining about it . Chose your battles wisely grasshopper.

 

[crossman]

Quog!

I am fighting no battles here. I am a seeker of the truth. And old electrician's tales are fair game.

Example: "Electricity always takes the least resisitve path to ground"

Wrong.

Example: When connecting a single pole switch for a light, the hot to the light must be a white conductor, remarked black. (and I am talking about conduit to the switch box.

Wrong

Just seeking the truth.

And when was it a problem to argue code on this forum? Should I just let the good folks go on believing and perhaps enforcing something that isn't really in the code?

I suppose the real reason is that it is entertaining for me.:roll:

 

[chris kennedy]

Unless you used cast setscrew fittings of course and then you have a problem.

Not listed for grounding???

 

[Smart $]

Equipment is plural. See article 100 definition of "equipment".

Equipment is "a general term, including material, fittings, devices, appliances, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation."

Material and fittings is definitely plural, and EMT is certainly material, and fittings means gobs and gobs of fittings.:smile:

Yes, but "equipment" in the English language is also singular, and the context of the statement dictates it to be used in this sense here.

Grammatically evaluate this sentence: We can count in multiples of one, twos, or three. Is "twos" correct grammar, or should it be "two"?

 

[mivey]

Crossman,
Do you think this post:
http://forums.mikeholt.com/showpost.php?p=861076&postcount=7
means that the conduit is no longer the official ECG because you have pulled a grounding conductor in the conduit?

 

[quogueelectric]

Not listed for grounding???

It was a joke about annother thread.

 

[quogueelectric]

Quog!

I am fighting no battles here. I am a seeker of the truth. And old electrician's tales are fair game.

Example: "Electricity always takes the least resisitve path to ground"

Wrong.

Example: When connecting a single pole switch for a light, the hot to the light must be a white conductor, remarked black. (and I am talking about conduit to the switch box.

Wrong

Just seeking the truth.

And when was it a problem to argue code on this forum? Should I just let the good folks go on believing and perhaps enforcing something that isn't really in the code?

I suppose the real reason is that it is entertaining for me.:roll:

Alright alright you win. I dont know what you won but you won this one.:grin:

 

[rexowner]

I believe Pierre is correct. It is a violation.

Playing English major, 250.148 says:
...any equipment grounding conductor(s)...
shall be connected within the box or to the box...

"any ... conductor(s)" in 250.148 means both
the #12 grounding conductor and the EMT shall be
connected. You can't not connect the #12, as it
is one of the "any... conductors(s)."

WRT your question of why it says "within the box
or to the box", I believe the "within" is to allow
a splice of e.g. another wire that that would be
connected to the box.

 

[wwhitney]

Playing English major, 250.148 says: ...any equipment grounding conductor(s)... shall be connected within the box or to the box...

"any ... conductor(s)" in 250.148 means both the #12 grounding conductor and the EMT shall be connected. You can't not connect the #12, as it is one of the "any... conductors(s)."

If I understand Crossman's point, it is that the #12 wire is already connected to the box. That is via "box -- EMT -- panel case -- grounding bar -- #12 wire". So from that point of view, why is it necessary to add another connection within the box?

Yours, Wayne

 

[rexowner]

If I understand Crossman's point, it is that the #12 wire is already connected to the box. That is via "box -- EMT -- panel case -- grounding bar -- #12 wire". So from that point of view, why is it necessary to add another connection within the box?

Yours, Wayne

Thanks, Wayne, I think I may have been missing a subtle
part of the argument.

I guess the argument is the definition of the word "to"
in 250.148. My interpretation is that the way the word
"to" is used is synonymous with "directly to". As
evidence of this interpretation, refer to the Exception
which states:
"... shall not be required to be connected to the other
EGCs or to the box."
If the definition of "to" included the path "through the
groundbar, panel, emt to the box" the word "or" (to the
box) would not be used because by that definition the
other EGCs would be connected to the box and the "or"
would be an "and." I believe the use of the word "to"
is used consistently this way in 250.148.

I think the above is a reasonable interpretation of what
250.148 states, and thus enforceable by the AHJ.

 

[cowboyjwc]

I will agree that EMT is a grounding conductor, but what 250.148(C) says is ".......and a metal box by means of a gronding screw that shall be used for no other purpose, or a listed grounding device."

I would take to mean a listed grounding device as a clip or a grounding bushing, etc. Now if you can show me that an EMT connector is a "listed grounding device" (must produce paper work or the box).

Now as an inspector I would agree with what some of the others have said or the way I read it anyways, If the cost of the grounding screw and the time to put it in is a factor, then you could have saved a bunch of money by not installing a grounding conductor at all. If you are going to mix methods I would make you comply with both.

 

[iwire]

I have seen several folks who indicated they believed it was mandatory, in my original scenario, that the EGC wire be connected to the box, inside the box, with a jumper wire.

Count me as one of those persons assuming the conductors are spliced or terminated in that particular box.

 

[crossman]

Count me as one of those persons assuming the conductors are spliced or terminated in that particular box.

Spliced, yes. Terminated to the box... well, the code says it must be connected to the box. And one of the permissible means of connection is through the EMT and fittings.

Your thoughts?

 

[chris kennedy]

Your thoughts?

I'll say 931 posts.

Closest without going over wins one of these.

 

[crossman]

I will agree that EMT is a grounding conductor, but what 250.148(C) says is ".......and a metal box by means of a gronding screw that shall be used for no other purpose, ________ or a listed grounding device."

I am discussing the 2008 NEC. The CMP added "equipment listed for grounding" where I added the blank into your quote above. Equipment is defined as being material and fittings among other things. Certainly EMT falls within this definition. So the EGC wire can be connected to the box with EMT and fittings.

If the cost of the grounding screw and the time to put it in is a factor, then you could have saved a bunch of money by not installing a grounding conductor at all. If you are going to mix methods I would make you comply with both.

Comply with both? If I wanted to run an EGC wire and connect it only at the load, and use the EMT to connect the boxes to the EGC wire, then we are code compliant. You would make an EC do something that is not required by code?

And, what difference is it from an installation as in 250.146(D) for isolated receptacles? 250.146(D) doesn't require the EGC wire to be connected to the boxes... it only has to be connected to the load. At this point, it may be the CMP realized their mistake in 2005 and added "equipment listed for grounding" which includes the EMT.

I suppose in an idealistic world, everyone, both electrician and inspector could agree with what the code says. Right now, intelligent people on this forum are split on what this section means. That is a definite problem.

Tomorrow, I'll go to the NFPA site and see if there is any commentary on this change.

 

[crossman]

Yes, but "equipment" in the English language is also singular, and the context of the statement dictates it to be used in this sense here.

I don't see how the context excludes a run of EMT. A complete run of EMT from a panel to a load and including fittings is equipment, regardless of whether equipment is singular or not. Equipment can be numerous items connected together as a whole, as in a complete conduit system.

Since this is a change in the 2008 code, there may be some commentary on the NFPA site. I would look it up tonight, but I am on dial-up. Hopefully I can check it out in the morning. Or perhaps one of you can look it up tonight?

 

[quogueelectric]

Yet the same cmp will allow a fixture manufacturer to install a solid 18 awg wire as suitable ground equipment. The lobbyists with thier big cash pockets have finaly got through to the cmp.

 

[frizbeedog]

Since this is a change in the 2008 code, there may be some commentary on the NFPA site. I would look it up tonight, but I am on dial-up. Hopefully I can check it out in the morning. Or perhaps one of you can look it up tonight?

The following information was found Here

250.148 and 250.148(C): These changes clarify the present requirement in
more prescriptive language.

The changes that were made:

Red: removed.

Green: new

250.148 and 250.148(C): Revise first paragraph of 250.148 and 250.148(C) as
follows:
250.148 Continuity and Attachment of Equipment Grounding Conductors
to Boxes
Where circuit conductors are spliced within a box, or terminated on equipment
within or supported by a box, any equipment grounding conductor(s) associated
with those circuit conductors shall be spliced or joined connected within the
box or to the box with devices suitable for the use in accordance with
250.148(A) through (E). ?
(C) Metal Boxes. A connection shall be made between the one or more
equipment grounding conductors and a metal box by means of a grounding
screw that shall be used for no other purpose, equipment listed for grounding,
or a listed grounding device.

Some rejected proposals....but you'll need to go to page 63 of The Document to read the proposals in thier entirety.

Substantiation: This section gives the impression that an equipment
grounding conductor is in, all instances, not required to be bonded to the metal
box if the wire is not broken in the box. When say 4 in. PVC is used with a
metal box the box is left floating. Thus can become hot!
Panel Meeting Action: Reject
Panel Statement: The proposed revision does not add clarity or improve
usability to this section. The concerns of the submitter are already addressed in
the requirements contained in Sections 250.148 and 250.148(C).
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15

Substantiation: Edit. Enclosures other than ?boxes? should be included.
Reference to circuit conductors is superfluous and irrelevant and limits the
requirements to where circuit conductors are spliced or terminated on
equipment within or supported by a box but not where conductors run through
without a splice. Wire type grounding and bonding conductors should be
specified, as grounding and bonding can be done by other means. Bonding
conductors (wire type) may also enter enclosures by way of raceways per
250.102(E). Where installed on the outside of raceways, terminal fittings with
lugs provide for attachment. The phrase ?or to the box? appears to literally be
an option NOT to connect it to the box. ?Devices suitable for use? is
superfluous, already covered by (A). In (A), a reference to 250.8 is more
specific for grounding and bonding conductors. In (B), a reference to bonding
conductors is also applicable. The proposed reference to 250.8 in (A) makes
present (C) and (E) unnecessary. The requirement in present (D) should apply
whether grounding is required or done by choice.
Panel Meeting Action: Reject
Panel Statement: This proposal is not editorial. The is no technical
substantiation to remove the phrase ?spliced or joined within the box or to the
box ?. The proposed text does not add clarity.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15

Substantiation: 250.148 states where circuit conductors are spliced within in
a box, or terminated on equipment within or supported by a box, any
equipment grounding conductor(s) associated with those circuit conductors
shall be spliced or joined within the box or to the box with devices suitable for
the use in accordance with 250.148(A) through (E).
250.148(C) only makes reference to metal boxes. Addressing pull boxes
specifically, would help eliminate any confusion with the interpretation of this
section of the code.
Panel Meeting Action: Reject
Panel Statement: The proposal does not add clarity or improve usability of
this section. The concerns of bonding are already addressed in Sections
250.110, 250.134, and 314.4.
Number Eligible to Vote: 15
Ballot Results: Affirmative: 15

 

[iwire]

Spliced, yes. Terminated to the box... well, the code says it must be connected to the box. And one of the permissible means of connection is through the EMT and fittings.

Your thoughts?

My thoughts are simply that if a wire EGC is run into a box and it's associated circuit conductors splice or terminate in that box then the wire EGC must connect to the box.

You don't get to count the EMT and it associated fittings.

 

[iwire]

Yet the same cmp will allow a fixture manufacturer to install a solid 18 awg wire as suitable ground equipment. The lobbyists with thier big cash pockets have finaly got through to the cmp.

The CMP does not control how manufacturers ground equipment.