Neutral Brought to Disconnect Switch

infinity

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New Jersey
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Journeyman Electrician
I had a question today about a violation for not bringing the neutral to the disconnect switch. Here's the setup, a trough with a 3P, 30 amp non-fused disconnect switch connected via an offset nipple. The two conductors (H&N) run into the trough, the hot goes into the disconnect switch via the nipple and the switch leg comes out via the same nipple (a simple switch loop). Both the switch leg and the neutral continue on to the load. Inspector says that you need to run the neutral into and back out of the disco. Electrician says no, it's no different than feeding a switch with two conductors and no neutral (a switch loop). Inspector wants a neutral bar installed and the neutral run into and back out of the disco. Opinions?
 
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xformer

Senior Member
Location
Dallas, Tx
I had a question today about a violation for not bringing the neutral to the disconnect switch. Here's the setup, a trough with a 3P, 30 amp non-fused disconnect switch connected via an offset nipple. The two conductors (H&N) run into the trough, the hot goes into the disconnect switch via the nipple and the switch leg comes out via the same nipple (a simple switch loop). Both the switch leg and the neutral continue on to the load. Inspector says that you need to run the neutral into and back out of the disco. Electrician says no, it's no different than feeding a switch with two conductors and no neutral (a switch loop). Inspector wants a neutral bar installed and the neutral run into and back out of the disco. Opinions?
What type of raceway is this installed in?
 

augie47

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Location
Tennessee
Other than as listed in the exceptions(non-ferrous, etc), I would say that not bringing the neutral into the disconnect is a violation of 300.3(B)but I have never seen it enforced on circuits of that low an amperage.
 

GoldDigger

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Staff member
But even though that section might require it to be present in the box, I do not see any reason that it has to be terminated for easy access within the box. (Separate thread on that one....)
 

iwire

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Location
Massachusetts
Other than as listed in the exceptions(non-ferrous, etc), I would say that not bringing the neutral into the disconnect is a violation of 300.3(B)but I have never seen it enforced on circuits of that low an amperage.
As far as 300.3(B) IMO the 'where used' lets the grounded conductor out of the requirement in this application.

From a electrical standpoint there is no heating as the hots go out and in via the same conduit.
 

augie47

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Location
Tennessee
As far as 300.3(B) IMO the 'where used' lets the grounded conductor out of the requirement in this application.

From a electrical standpoint there is no heating as the hots go out and in via the same conduit.
But in your OP your stated the hots and neutral continued on to the load... would this not constitute "where used" ?
 

infinity

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Location
New Jersey
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Journeyman Electrician
If you were to change the 30 amp disconnect to a single pole switch would there be no argument since electrically to two installations would be the same?
 

iwire

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Location
Massachusetts
But in your OP your stated the hots and neutral continued on to the load... would this not constitute "where used" ?
If we read it the way you suggest there would never have been dead end 3-way switches. Every switch that controlled a circuit with a grounded conductor would have to a grounded conductor at the switch and the NFPA would not have had to recently add the direct requirement to bring a grounded conductor to wall switches.
 

infinity

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Location
New Jersey
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Journeyman Electrician
If this is required by 300.3(B) then wouldn't the EGC need to be run in and out of the switch as well?

(B) Conductors of the Same Circuit. All conductors of
the same circuit and, where used, the grounded conductor
and all equipment grounding conductors and bonding con-
ductors shall be contained within the same raceway, auxil-
iary gutter, cable tray, cablebus assembly, trench, cable, or
cord, unless otherwise permitted in accordance with
300.3(B)(1) through (B)(4).
Also what section specifically allows for a two wire switch loop run down to a single pole switch?
 

infinity

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Location
New Jersey
Occupation
Journeyman Electrician
I agree.

I don't see what this would do other than waste time and copper.
I agree, since it's eletrically identical to a two wire switch loop it seems fine to me. The contractor told me that he would run the neutral into and back out of the switch to make the inspector happy. Seems like a waste of time and money as you've suggested.
 
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