The Case Of The Misplaced Bonding Requirement

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George Stolz

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Today at lunch I whipped out an old issue of EC&M when I was digging around for a phone book. It was one my co-worker had seen and was looking for the other day, so I carried it back in with me to lunch.

A while back, we were short on water pipe clamps, so I told him not to bother with the clamp on the house side of the water meter, because it wasn't required anyway. The interior piping was plastic PEX pipe. I then volunteered it wasn't necessary even if the piping were metallic, because we're making our connection on the street side of the meter. I said, the grounding electrode connection can't rely on water meters, but the bonding connection has no such stipulations.

Half of you are thinking, "You idiot."
The other half are reaching for their codebooks before saying, "You idiot."

As it so happens (as fortunately, it does) he happened to turn to Mike Holt's Grounding vs. Bonding article in the back, and happened across this picture. He said, "It says here that the jumper's required for the bonding connection to the interior metal water piping, regardless of the GEC connection."

"Nah, the bonding described in 250.104 doesn't say anything about the water meter. That's a grounding requirement, in 250.-fifty something," I casually replied.

"So, you're saying this Mike Holt fella's wrong?"

"Well...no. You're looking at the picture wrong. Uh ... the point he's making with the picture is ... uh ... " (studying closely) " ... that the GEC connection can be made at the 5' mark, and a seperate conductor can be used to jumper the meter," I said, with due hesitation.

"I'm reading the text. It says 'bonding connection.'"

"Well, that can't be right - see? 250.53(D)(1). That's grounding. Look, I'll go get the book."

Imagine my chagrin when I read the following:
250.53(D)(1) Continuity. Continuity of the grounding path or the bonding connection to interior piping shall not rely on water meters or filtering devices and similar equipment.

To which I loudly proclaimed, "That's not where that belongs!" :D

Who's with me? 8)
 

iwire

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Massachusetts
Hey you would not want it a cake walk would ya? :lol:

Get your hands on say a 1996 NEC and try to make sense of 250, IMO we are very lucky it got as organized as it is now. :shock:
 

George Stolz

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Windsor, CO NEC: 2017
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Service Manager
Re: The Case Of The Misplaced Bonding Requirement

(Thanks for the reply, Bob.) :)

Cough! Cough!
georgestolz said:
To which I loudly proclaimed, "That's not where that belongs!" :D

Who's with me? 8)
I pondered this aloud on the chat room over yonder, and heard some interesting opinions. I then went to sleep and forgot them because they weren't written down. :D

Anybody think this is the appropriate spot, and that my opinion is incorrect?
 

jwelectric

Senior Member
Location
North Carolina
georgestolz said:
Who's with me? 8)

George let?s add the first part to it

(D) Metal Underground Water Pipe. Where used as a grounding electrode, metal underground water pipe shall meet the requirements of 250.53(D)(1) and (D)(2).
(1) Continuity. Continuity of the grounding path or the bonding connection to interior piping shall not rely on water meters or filtering devices and similar equipment.

The title of this section is;

250.53 Grounding Electrode System Installation.

If I understand things the correct way then (D)(1) will only apply to 250.53 Grounding Electrode System Installation and have no reflection on 250.104
 

Smart $

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Location
Ohio
I don't believe 250.53(D)(1) to be in the wrong place, but rather not repeated or referenced in 250.104 as it should be.
 

George Stolz

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Location
Windsor, CO NEC: 2017
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Service Manager
Mike, I'd say you are correct. So let's take it as a given that only when the water pipe is a GE, this applies.

What I find interesting, and this is going way out on a theoretical limb here, is: What does the interior piping do for the Grounding Electrode? The requirements in this Part are effectively, Things A Grounding Electrode System Must Have To Perform and to Last For A Long Time.

What benefit does the interior piping give the GE? I think that makes the wording of this requirement especially poor. (Off the top of my head) every other word in this Part is to bolster the GES, not to enhance unrelated bonding connections.
 

mvannevel

Senior Member
Smart $ said:
I don't believe 250.53(D)(1) to be in the wrong place, but rather not repeated or referenced in 250.104 as it should be.
I'd have to agree with you. This really should be referenced in 250.104 also. If it were, it would help with questions like Mike had in his water heater bond-around post.

Whether or not the metal underground water pipe is present (and used as a grounding electrode), that interior metal piping system needs to be bonded. That's a given. However, my opinion is that anything that would interrupt the continuity of this piping also needs to be bonded around. Granted, where it's mentioned in 250.53(D)(1), it's in reference to Grounding Electrode System Installation. But, I don't believe this relieves us of the responsibility to maintain a bond to all sections of the interior metal piping system. In fact, you could actually look at that piping as a number of different metal water piping systems, e.g. the hard water system, the soft water system, the cold water system, the hot water system, the filtered water system, and the unfiltered water system. If anything exists within or between those sytems that interrupts the continuity, it should be bonded around. At least that's the way I see it.

Something we see frequently around here is non-metallic water filter bodies. Often, these are located with a considerable amount of piping on either side of the filter. Most of the wells are brought into the structure in pvc, so the connection to the metal is bonding only. My opinion is that this filter body needs to be bonded around to maintain the continuity.

georgestolz said:
What benefit does the interior piping give the GE? I think that makes the wording of this requirement especially poor. (Off the top of my head) every other word in this Part is to bolster the GES, not to enhance unrelated bonding connections.
It provides no benefit George. I think this was included here to indicate that attaching the GEC to the metal water piping within the first 5' doesn't necessarily serve to bond the piping if you have meters and filters and the like in the line. Like Smart $ said, it should be repeated, or at least referenced, in 250.104.

And, what the heck, if the plumbers keep dumbing down their trade with pvc and PEX, maybe this won't be much of an issue in a few years...
 
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