detached garage overhead wire

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bigdp

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Me and local inspector have a differance on how the overhead feeders should be and I would like others input. Here is what i did- I ran #4(AL) triplex wire from the house to the garage (2H, 1N) at the disconnect on the garage I have a ground wire #6 that attaches to the ground rod. This is an old garage from the 1940's or 50's there is no other grounding means. This is a 240v 60amp system disconnect outside with a subpanel inside. My inspector failed me because- 1. the overhead wire had no ground wire that ran with the others from the house panel. I added the ground wire to the overhead wires and then I was turned down again because the 3rd wire on the triplex was used as the neutral and was not insulated. In short is the inspector correct in saying that it is required to have the 4th wire a ground and in this case when using the triplex that 3rd cable has to be insulated. I am looking at NEC 250.32. Thanks
 
bigdp said:
Me and local inspector have a differance on how the overhead feeders should be and I would like others input. Here is what i did- I ran #4(AL) triplex wire from the house to the garage (2H, 1N) at the disconnect on the garage I have a ground wire #6 that attaches to the ground rod. This is an old garage from the 1940's or 50's there is no other grounding means. This is a 240v 60amp system disconnect outside with a subpanel inside. My inspector failed me because- 1. the overhead wire had no ground wire that ran with the others from the house panel. I added the ground wire to the overhead wires and then I was turned down again because the 3rd wire on the triplex was used as the neutral and was not insulated. In short is the inspector correct in saying that it is required to have the 4th wire a ground and in this case when using the triplex that 3rd cable has to be insulated. I am looking at NEC 250.32. Thanks
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Sorry, but I think the inpector is correct. You should be using quadplex with the bare messenger used as the EGC and the 3 insulated conductors as L, L, N.
 
My opinion would be that the install would be in violation IF the equipment ground was not identified as specified in 250.119.
I think the Code would allow either the equipment ground or grounded conductor to be bare, however, since they are in the same aerial cable, not both.
Common practice would dictate the equipment grounding be the bare conductor but from an NEC standpoint either can be.
 
I think the inspector is correct as well.

It seems to me that this is a feeder and thus requires 4 conductors (L1, L2, N, G), 3 of which must be insulated. the EGC can be bare.

A ground rod is also required.
 
the newly added grounding conductor is insulated. It is also supported with a strain relif atched to the 1-1/2 ridged mast on both sides.
 
petersonra said:
I think the inspector is correct as well.

It seems to me that this is a feeder and thus requires 4 conductors (L1, L2, N, G), 3 of which must be insulated. the EGC can be bare.

A ground rod is also required.
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"3 of which must be insulated.". I'm having a difficult time backing that up by Code. Can you advise ?
I see where, if it is insulated, how it must be identified, etc, but I can't see where it's required to be insulated...
almost always is, probably should be, but I can;t find the requirement.
 
225.4 Conductor Covering.
Where within 3.0 m (10 ft) of any building or structure other than supporting poles or towers, open individual (aerial) overhead conductors shall be insulated or covered. Conductors in cables or raceways, except Type MI cable, shall be of the rubber-covered type or thermoplastic type and, in wet locations, shall comply with 310.8. Conductors for festoon lighting shall be of the rubber-covered or thermoplastic type.
Exception: Equipment grounding conductors and grounded circuit conductors shall be permitted to be bare or covered as specifically permitted elsewhere in this Code.
 
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250.32 Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s).



(B) Grounded Systems.
(1) Supplied by a Feeder or Branch Circuit. An equipment grounding conductor, as described in 250.118, shall be run with the supply conductors and be connected to the building or structure disconnecting means and to the grounding electrode(s). The equipment grounding conductor shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded. The equipment grounding conductor shall be sized in accordance with 250.122. Any installed grounded conductor shall not be connected to the equipment grounding conductor or to the grounding electrode(s).
Exception: For installations made in compliance with previous editions of this Code that permitted such connection, the grounded conductor run with the supply to the building or structure shall be permitted to serve as the ground-fault return path if all of the following requirements continue to be met:

  1. An equipment grounding conductor is not run with the supply to the building or structure.
  2. There are no continuous metallic paths bonded to the grounding system in each building or structure involved.
  3. Ground-fault protection of equipment has not been installed on the supply side of the feeder{s).
If the grounded conductor is used for grounding in accordance with the provision of this exception, the size of the grounded conductor shall not be smaller than the larger of either of the following:

  1. That required by 220.61
  2. That required by 250.122
 
Perhaps my old eyes are missing something, but I stll see nothing requiring the grounded or grounding to be insulated other than 250.23 requiring they not be "connected"... am I missing something ??
 
augie47 said:
Perhaps my old eyes are missing something, but I stll see nothing requiring the grounded or grounding to be insulated other than 250.23 requiring they not be "connected"... am I missing something ??
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Exception: Equipment grounding conductors and grounded circuit conductors shall be permitted to be bare or covered as specifically permitted elsewhere in this Code.


I would say either or
 
augie47 said:
Perhaps my old eyes are missing something, but I stll see nothing requiring the grounded or grounding to be insulated other than 250.23 requiring they not be "connected"... am I missing something ??
Click to expand...

225.4 Conductor Covering.
Where within 3.0 m (10 ft) of any building or structure other than supporting poles or towers, open individual (aerial) overhead conductors shall be insulated or covered. Conductors in cables or raceways, except Type MI cable, shall be of the rubber-covered type or thermoplastic type and, in wet locations, shall comply with 310.8. Conductors for festoon lighting shall be of the rubber-covered or thermoplastic type.


Exception: Equipment grounding conductors and grounded circuit conductors shall be permitted to be bare or covered as specifically permitted elsewhere in this Code.

Augie, the permitted areas are,
For the grounded conductor the exception would be 250.32 for existing conditions and 230.22 for service conductors. All other places if it was bare it could be in contact with the grounding conductor and that would be against 250.24(A)5
For the equipment ground 250.118 allows it to be bare.
 
bigdp said:
I am looking at NEC 250.32. Thanks
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250.32 is for existings conditions, like if the original triplex got knocked down and you are only replaceing it. If you are putting in a new panel and feeder to the garage, it is required to keep the grounded neutral conductor seperated from the equipment ground.
 
RUWired said:
225.4 Conductor Covering.
Where within 3.0 m (10 ft) of any building or structure other than supporting poles or towers, open individual (aerial) overhead conductors shall be insulated or covered. Conductors in cables or raceways, except Type MI cable, shall be of the rubber-covered type or thermoplastic type and, in wet locations, shall comply with 310.8. Conductors for festoon lighting shall be of the rubber-covered or thermoplastic type.


Exception: Equipment grounding conductors and grounded circuit conductors shall be permitted to be bare or covered as specifically permitted elsewhere in this Code.

Augie, the permitted areas are,
For the grounded conductor the exception would be 250.32 for existing conditions and 230.22 for service conductors. All other places if it was bare it could be in contact with the grounding conductor and that would be against 250.24(A)5
For the equipment ground 250.118 allows it to be bare.
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My point, perhaps an incorrect one, is somewhat along the same line.
200.2 allows the grounded conductor to be bare, 250.118 allows the equipment grounding conductor to be bare. Taking only those Code sections into account, either of those conductors (alone) in his aerial run could be the bare conductor. Both could not be if they were in contact due to 250.24 as you cite.
If either is insulated, they would have to be of a color designated in 250.119 or 200.6.
If he elected to make the equipment ground the insulated conductor and identified it properly, I don't see a violation. Not the way I would do it, but allowable, IMHO.
 
augie47 said:
My point, perhaps an incorrect one, is somewhat along the same line.
200.2 allows the grounded conductor to be bare, 250.118 allows the equipment grounding conductor to be bare. Taking only those Code sections into account, either of those conductors (alone) in his aerial run could be the bare conductor. Both could not be if they were in contact due to 250.24 as you cite.
If either is insulated, they would have to be of a color designated in 250.119 or 200.6.
If he elected to make the equipment ground the insulated conductor and identified it properly, I don't see a violation. Not the way I would do it, but allowable, IMHO.
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I don't think I agree. By your logic, 200.2 would allow the neutral to be bare in, say, a branch circuit or a regular feeder, and of course we can't do that. To me, it is implied by 250.24(A)(5), then 200.2(A) says it must be insulated the same as (for circuits less than 1000 volts) the ungrounded conductors.
 
I think that some clarification may be in order regarding the OP. It is my understandind that he has triplex, with a bare messenger being used as the neutral in a 120/240 feeder. If that is the case, this would not comply with 250.24(A)(5) as the messenger would likely be attached without insulators. Others have mentioned 225.4, but I don't think that applies here, as I don't think this is an open counductor on insulator installation.
 
Given the use of a metallic wedge clamp to support the triplex and the code's very broad definition of equipment, it would be a violation of 250.24(A)(5) to use the bare conductor as the grounded conductor.
 
While we are on the subject of grounded conductor insulation, Am I correct in saying that 250.24(A)(5) is what tells us this? The OP has caused me to realize that this seems a little fuzzy. What am I missing?
 
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