250.148 question

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Rcr29kh1

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Hello all, new to forum and first post. I read it all the time for personal knowledge and entertainment. Here goes first question:
250.148 says that any circuits that are spliced in a junction box, the associated ground wire needs to be bonded to the junction box. At my job, the contractor has installed a 4' x 4' junction box consisting of 6 sets of parallel feeders, 600 MCM. For whatever reason they did not pull straight through the pull box and elected to make a splice of all conductors. They only took one of the grounds and bonded it to the pull box leaving the other grounds butt spliced and run straight through. I explained that they needed to bring all the grounds together with one bonding to the pull box. They replied that they do not need to do this since it is parallel feeders. Any thoughts?
 
IMO that section is not very clear and be interpreted either way. IMO since each raceway has a "full size" EGC then one bonding jumper to the box is sufficient.
 
I don't see making an issue but I'm not sure I agree with my astute colleagues.If the powers that be deem it necessary to pull a grounding conductor in each conduit to the termination point, it would seem the same logic (or lack thereof) would require all the EGs be connected at every point there are needed.
A similar question was asked recently about a 4" sq box and the consensus was that all the EGs had to be connected together and bonded to the box.
 
I agree that the code is not completely clear on this, but because of the inductive reactance that will occur where the EGC from only one conduit is bonded to the box and there is a fault to the box from an ungrounded conductor in one of the other conduits, I think all of the EGCs should be bonded to the box.
 
don_resqcapt19 said:
I agree that the code is not completely clear on this, but because of the inductive reactance that will occur where the EGC from only one conduit is bonded to the box and there is a fault to the box from an ungrounded conductor in one of the other conduits, I think all of the EGCs should be bonded to the box.
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The NEC doesn't seem to address this either because if you had a number of different conduits, but only one of the conduits had conductors that were spliced, only the spliced set would require the jumper to the box.
 
infinity said:
The NEC doesn't seem to address this either because if you had a number of different conduits, but only one of the conduits had conductors that were spliced, only the spliced set would require the jumper to the box.
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How could this or the OP's situation not violate 310.10(H)?
 
chris kennedy said:
I can send you a code book, I have extras.
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I am just too lazy to grab the 2014 from the truck.:)

chris kennedy said:
310.10(H)(2)(5) Terminated in same manner.

And yes it applies to EGC's.
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Interesting because in general the rules do not apply to EGCs

(H) Conductors in Parallel.
(1) General. Aluminum, copper-clad aluminum, or copper
conductors, for each phase, polarity, neutral, or grounded
circuit circuit conductor
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How about 2014 310.(H)(3)?:?

(3) Separate Cables or Raceways. Where run in separate
cables or raceways, the cables or raceways with conductors
shall have the same number of conductors and shall have
the same electrical characteristics. Conductors of one
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor shall not be required to
have the same physical characteristics as those of another
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor.
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Anyway, the reason my first post in this thread was short an specific to the size of the EGC was because like Don I do not find the code clear on this specific issue. :)
 
Forget 310.10(H)...

Let's go directly to the horse's mouth.

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 connected
within the box or to the box with devices suitable for
the use in accordance with 250.148(A) through (E).
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Seems pretty clear to me... all the parallel EGC's must be connected together in the box. Even splicing just one conductor of one set would require all the EGC's be connected together.
 
Smart $ said:
Seems pretty clear to me... all the parallel EGC's must be connected together in the box. Even splicing just one conductor of one set would require all the EGC's be connected together.
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OK, that makes two times today I am going to change my view.

I have to agree with the above.
 
Smart $ said:
Forget 310.10(H)...

Let's go directly to the horse's mouth.



Seems pretty clear to me... all the parallel EGC's must be connected together in the box. Even splicing just one conductor of one set would require all the EGC's be connected together.
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But if only one or more conductors in one set are spliced, would that not violate the conditions for paralleled wire sets?
 
chris kennedy said:
Terminated in the same manner.

If I take one of the EGC's, splice it and terminate it to the J-box I feel that is a violation.
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Well, yeh...

My previous reply was based on the splicing of a circuit conductor, which then requires the EGC's be connected together... not splicing and terminating only one EGC. Either way, it amounts to all the EGC's must be connected together.
 
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 connected
within the box or to the box with devices suitable for
the use in accordance with 250.148(A) through (E).
Click to expand...

I think the phrase in red is key.

Only the EGC associated with the "circuit conductors ... spliced within a box, or terminated on equipment within or supported by a box" would need to be connected to the box. Otherwise it would be an extreme contortion of the English language.
 
petersonra said:
I think the phrase in red is key.

Only the EGC associated with the "circuit conductors ... spliced within a box, or terminated on equipment within or supported by a box" would need to be connected to the box. Otherwise it would be an extreme contortion of the English language.
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I think we're pretty much all in agreement with that part.

What is not clear is if none of the parallel conductors are spliced, but one of the associated EGC's is and connected to the box. For this, we have to resort to 310.10(H)... and a few of us are saying that would be a violation also.
 
If the box contained say 5 sets of 500 kcmil unspliced but one set of spliced #12's then the only bonding jumper to the box required would be a #12?
 
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