Question on 2011 switch wiring requirements

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mshields

mshields

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Boston, MA
404.2 (C) has been changed in the 2011 code. I have pasted in the new section below. Can anyone explain to me what a simple switchleg is to now look.

I also don't follow the exception nor the two conditions sited in this exception. Any clarification would be greatly appreciated.



404.2 Switch Connections.

(A) Three-Way and Four-Way Switches. Three-way and four-way switches shall be wired so that all switching is done only in the ungrounded circuit conductor. Where in metal raceways or metal-armored cables, wiring between switches and outlets shall be in accordance with 300.20(A).

Exception: Switch loops shall not require a grounded conductor.

(B) Grounded Conductors. Switches or circuit breakers shall not disconnect the grounded conductor of a circuit.

Exception: A switch or circuit breaker shall be permitted to disconnect a grounded circuit conductor where all circuit conductors are disconnected simultaneously, or where the device is arranged so that the grounded conductor cannot be disconnected until all the ungrounded conductors of the circuit have been disconnected.

(C) Switches Controlling Lighting Loads. Where switches control lighting loads supplied by a grounded general purpose branch circuit, the grounded circuit conductor for the controlled lighting circuit shall be provided at the switch location.


Changed From 2008

?404.2(C): Added new requirement covering installation of grounded conductor at all switch locations where lighting loads are controlled.


Exception: The grounded circuit conductor shall be permitted to be omitted from the switch enclosure where either of the following conditions in (1) or (2) apply:

(1) Conductors for switches controlling lighting loads enter the box through a raceway. The raceway shall have sufficient cross-sectional area to accommodate the extension of the grounded circuit conductor of the lighting circuit to the switch location whether or not the conductors in the raceway are required to be increased in size to comply with 310.15(B)(3)(a).

(2) Cable assemblies for switches controlling lighting loads enter the box through a framing cavity that is open at the top or bottom on the same floor level, or through a wall, floor, or ceiling that is unfinished on one side.
 
Basically if the wall is open on one side or unfinished at the top or bottom where one could get a wire in the wall easily then you need not do anything different. The other exception is if the switches are piped in from an area where a neutral can be added later.

Otherwise a neutral needs to be install at every switch location on every circuit so that a device that needs a neutral may be installed. This includes 3 way dead end switches.
 
mshields said:
(2) Cable assemblies for switches controlling lighting loads enter the box through a framing cavity that is open at the top or bottom on the same floor level, or through a wall, floor, or ceiling that is unfinished on one side.
Click to expand...

For the life of me, I can't picture what that means?:-?

Does that mean that it is accessible from a basement?
 
Awg-Dawg said:
For the life of me, I can't picture what that means?:-?

Does that mean that it is accessible from a basement?
Click to expand...
Open at the top and bottom on the same floor level does not mean open from the basement or attic. I have no idea where this wording comes from but if the rock does not go to the floor or to the ceiling then you have access to the switch.
 
Dennis Alwon said:
Open at the top and bottom on the same floor level does not mean open from the basement or attic. I have no idea where this wording comes from but if the rock does not go to the floor or to the ceiling then you have access to the switch.
Click to expand...

Yea, I get the same floor level part. It is the part where the floor is open, I just can't picture where that would apply. Oh well, I guess when I see it, I will get it.
 
mshields said:
404.2 (C) has been changed in the 2011 code. I have pasted in the new section below. Can anyone explain to me what a simple switchleg is to now look.

I also don't follow the exception nor the two conditions sited in this exception. Any clarification would be greatly appreciated.



404.2 Switch Connections.

(A) Three-Way and Four-Way Switches. Three-way and four-way switches shall be wired so that all switching is done only in the ungrounded circuit conductor. Where in metal raceways or metal-armored cables, wiring between switches and outlets shall be in accordance with 300.20(A).

Exception: Switch loops shall not require a grounded conductor.

(B) Grounded Conductors. Switches or circuit breakers shall not disconnect the grounded conductor of a circuit.

Exception: A switch or circuit breaker shall be permitted to disconnect a grounded circuit conductor where all circuit conductors are disconnected simultaneously, or where the device is arranged so that the grounded conductor cannot be disconnected until all the ungrounded conductors of the circuit have been disconnected.

(C) Switches Controlling Lighting Loads. Where switches control lighting loads supplied by a grounded general purpose branch circuit, the grounded circuit conductor for the controlled lighting circuit shall be provided at the switch location.


Changed From 2008

?404.2(C): Added new requirement covering installation of grounded conductor at all switch locations where lighting loads are controlled.


Exception: The grounded circuit conductor shall be permitted to be omitted from the switch enclosure where either of the following conditions in (1) or (2) apply:

(1) Conductors for switches controlling lighting loads enter the box through a raceway. The raceway shall have sufficient cross-sectional area to accommodate the extension of the grounded circuit conductor of the lighting circuit to the switch location whether or not the conductors in the raceway are required to be increased in size to comply with 310.15(B)(3)(a).

(2) Cable assemblies for switches controlling lighting loads enter the box through a framing cavity that is open at the top or bottom on the same floor level, or through a wall, floor, or ceiling that is unfinished on one side.
Click to expand...

The purpose for the new 404.2(C) is to assure that for every switch that controls a lighting load a neutral conductor is either initially installed or can be easily installed in the future. This will facilitate the future installation of devices such as occupancy sensors that require a neutral for safe operation, but that have in the past been improperly connected to the EGC. The exception cites two conditions in which the "in the future" requirement presumably is met. The first one, where the wiring method is a raceway, is fairly clear; but the convoluted wording of the second condition is very confusing.
 
Awg-Dawg said:
Yea, I get the same floor level part. It is the part where the floor is open, I just can't picture where that would apply. Oh well, I guess when I see it, I will get it.
Click to expand...

I think you got it right the first time you asked. If there's an unfinished basement below, then the floor is open on the underside.
 
Awg-Dawg said:
It is the part where the floor is open, I just can't picture where that would apply.
Click to expand...
Balloon framing. I've seen old houses where the wall cavities were open from crawl to attic, sometimes in both exterior and interior walls.

How that would apply to new construction, I can't say.
 
There are at least 3 threads on this same subject throughout the Forum.
Are there any other 2011 changes that people like/don't like?
Personally, I don't like the new kind of paper they use for the codebook.
Too slick & shiney.
db
 
The required neutral at the switch sounds like more of a "design manual" rather than a safety and min requirements issue. I am not complaing because its logical but seems like its more design than safety.
 
In some framing I can lift out a drop ceiling panel and see down the studwall because the sheetrock does not go to the top plate; other times the back side of the wall is unfinished. I'm thinking that if I can see the switch box I don't need a neutral?
 
mikeames said:
The required neutral at the switch sounds like more of a "design manual" rather than a safety and min requirements issue. I am not complaing because its logical but seems like its more design than safety.
Click to expand...


I can see that "design issue" But I can bet that it came from the fact that many new dimmers and wall switch controls need a nuetral.
Here in Ca. the title 24 energy code requirements make it necessary to add motion switches and dimmers. In the old days most of the motion switches used the grounding wire as a grounded conductor. This placed several miliamps on the Ground. Multiply this by many of these devices now required in the home and you now may have hit the threshold of tripping a GFCI or AFCI. WOOOPS? you know what happen then! This met the UL listing but I suppose they never figured that there would be more than one in a home.

As a result you will see many more of these devices with neutrals. You need a place to land the neutral right!.
 
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