Bonding of grounding electrode conductor conduit (sleeve)

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Natfuelbilll

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Job I'm on has grounding electrode conductor conduit (sleeve?) 30" below grade and extending 24" above grade to where the grounding electrode conductor is terminated onto structural steel. Does this conduit need to be bonded to the grounding electrode conductor? If so, is the bonding jumper required to be the same size as the grounding electrode conductor per 2014 250.64 (E)(1) and (3)?

Thanks guys!
 
If the sleeve is ferrous metal, yes. And the jumper would have to be the same size as the GEC. One issue I see here is that I don't know how you would bond the underground end in a compliant manner. Can't you use PVC instead?
 
According to that section a raceway needs to be continuous from point A to point B. I would question if that even applies to a sleeve.
 
infinity said:
According to that section a raceway needs to be continuous from point A to point B. I would question if that even applies to a sleeve.
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That is what the code language says, but how long can the ferrous metal sleeve be before the inductive reactance becomes an issue?
 
texie said:
If the sleeve is ferrous metal, yes. And the jumper would have to be the same size as the GEC. One issue I see here is that I don't know how you would bond the underground end in a compliant manner. Can't you use PVC instead?
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It only needs to be bonded to one end. Use a threaded grounding hub. Easy-peasy.
 
infinity said:
According to that section a raceway needs to be continuous from point A to point B. I would question if that even applies to a sleeve.
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The language says "electrically continuous". I don't think that it is required to be mechanically continuous so I say it applies to a ferrous sleeve.
 
texie said:
The language says "electrically continuous". I don't think that it is required to be mechanically continuous so I say it applies to a ferrous sleeve.
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You left out a few key words, it says "shall be electrically continuous from the point of attachment to cabinets or equipment to
the grounding electrode and shall be securely fastened to the ground clamp or fitting."
A sleeve would not be electrically continuous from one end to the other. If it were it would be a raceway and then 250.64(E)(1) would apply.

250.64(E) Raceways and Enclosures for Grounding Electrode Conductors.
(1) General. Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode and shall be securely fastened to the ground clamp or fitting. Ferrous metal raceways and enclosures shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor to create an electrically parallel path. Nonferrous metal raceways and enclosures shall not be required to be electrically continuous
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infinity said:
You left out a few key words, it says "shall be electrically continuous from the point of attachment to cabinets or equipment to
the grounding electrode and shall be securely fastened to the ground clamp or fitting."
A sleeve would not be electrically continuous from one end to the other. If it were it would be a raceway and then 250.64(E)(1) would apply.
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In my opinion he words "electrically continuous" are used because even a typical GEC in a raceway the raceway is often not mechanically connected to the grounding electrode. Yes. I'm aware that ground clamps are made with hub for this purpose but they are not required to be used. But you do have to bond the end of the raceway.
It seems to me that you are saying you could put a ferrous metal sleeve in the middle of a run of a GEC without bonding the ends to the GEC. I know of know AHJ that would agree with that.
 
texie said:
In my opinion he words "electrically continuous" are used because even a typical GEC in a raceway the raceway is often not mechanically connected to the grounding electrode. Yes. I'm aware that ground clamps are made with hub for this purpose but they are not required to be used. But you do have to bond the end of the raceway.
It seems to me that you are saying you could put a ferrous metal sleeve in the middle of a run of a GEC without bonding the ends to the GEC. I know of know AHJ that would agree with that.
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Like Don asked how long is too long for an unbonded sleeve? I don't know that answer.
 
Had this been an issue in that past the Code likely would have been more clearly written. Unless I can find more proof there is an issue here I’m going to drop the work order.
 
infinity said:
Like Don asked how long is too long for an unbonded sleeve? I don't know that answer.
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Because of the problem of high frequency components of lightning-induced currents, I would say that there is no length short enough to avoid the bonding requirement. Just as you cannot run an unbalanced current through a single hole in an enclosure regardless of the thickness of the metal of the enclosure.

A sleeve short enough to present a low enough impedance that it can be ignored would probably be too short to be a useful sleeve in the first place.
 
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