white wire in nm as switch leg

[Cleveland Apprentice]

Hi,

I had a discussion with co-worker yesterday and a little confused. I still don't have a recent 2011 code book yet. Anyway, he told me that the white conductor in nm cable can no longer be used as a switch leg. I disagreed with him. My arguments are that you could as long as you use re-identify the white wire and use the white as the source to a switch and the black as the load going to the light, so you don't end up with two white conductors feeding a fixture.

Also, this got me thinking if I could use the white as a traveller in 14/3 between 3 way switches as long as I re-identify the whites. I have in the past and will still do the following: run the power to the light first and a 14/3 to bottom of stairs and top of stairs (obviously will not work with 4 way) from the light I would connect the hot to the black wire of a 14/3 and the red/white will become the travellers to the second 3 way switch. From the second 3 way, the black will be become the common back to the light. Is this still legal. I use this method because of less wire and to make it a little easier. Thanks.

 

[jumper]

2011 NEC, new section.

404.2(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.
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
suffıcient 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.

Informational Note: The provision for a (future) grounded
conductor is to complete a circuit path for electronic lighting
control devices.

 

[Cleveland Apprentice]

Thanks Jumper! Wow, the NEC gets more ridiculous.

 

[jumper]

Thanks Jumper! Wow, the NEC gets more ridiculous.

Yeppers.

 

[jumper]

Thanks Jumper!.

You are welcome.

 

[jxofaltrds]

Hi,

I had a discussion with co-worker yesterday and a little confused. I still don't have a recent 2011 code book yet. Anyway, he told me that the white conductor in nm cable can no longer be used as a switch leg. I disagreed with him. My arguments are that you could as long as you use re-identify the white wire and use the white as the source to a switch and the black as the load going to the light, so you don't end up with two white conductors feeding a fixture.

Also, this got me thinking if I could use the white as a traveller in 14/3 between 3 way switches as long as I re-identify the whites. I have in the past and will still do the following: run the power to the light first and a 14/3 to bottom of stairs and top of stairs (obviously will not work with 4 way) from the light I would connect the hot to the black wire of a 14/3 and the red/white will become the travellers to the second 3 way switch. From the second 3 way, the black will be become the common back to the light. Is this still legal. I use this method because of less wire and to make it a little easier. Thanks.

Remember we (Ohio) are on the 2008 for resy 1,2,3 family still!

 

[kwired]

2011 NEC, new section.

404.2(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.
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
suffıcient 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.

Informational Note: The provision for a (future) grounded
conductor is to complete a circuit path for electronic lighting
control devices.

I would say that eliminates using the white conductor as an ungrounded conductor in many places but not all places.

 

[Speshulk]

Thanks Jumper! Wow, the NEC gets more ridiculous.

This one actually makes sense. Some of the newer switches for lighting control systems require a neutral. This change is an attempt to make sure a neutral is present at lighting switch locations so that in the event one of these type of switches is used, the installer doesn't use the ground wire for the neutral connection.

 

[hurk27]

I would say that eliminates using the white conductor as an ungrounded conductor in many places but not all places.

It is strange that it is still allowed in 200.7(C)(1) and even references 3-ways and 4-ways, but with this new rule it does make it almost imposable to ever do a dead end switch, or even use 14/3 or 12/3 between 3-way or 4-way switches unless you only do neutral pass through which will always put the load being fed to one 3-way and the hot at the other 3-way which limits us to how we can wire them? luckily we are still on the 2008 and it looks like the 2011 will not be adopted which we will jump to the 2014, so it will be a while before we have to worry about this unless I can get this change out of it before we adopt the 2014.

So about the only place you can use 200.7(C)(1) will be if you meet the conditions in 404.2(C)(2)

 

[resistance]

It is strange that it is still allowed in 200.7(C)(1) and even references 3-ways and 4-ways, but with this new rule it does make it almost imposable to ever do a dead end switch, or even use 14/3 or 12/3 between 3-way or 4-way switches unless you only do neutral pass through which will always put the load being fed to one 3-way and the hot at the other 3-way which limits us to how we can wire them? luckily we are still on the 2008 and it looks like the 2011 will not be adopted which we will jump to the 2014, so it will be a while before we have to worry about this unless I can get this change out of it before we adopt the 2014.

So about the only place you can use 200.7(C)(1) will be if you meet the conditions in 404.2(C)(2)

We barely get any work, so I?d be happy to wire any device...:weeping:

 

[kwired]

It is strange that it is still allowed in 200.7(C)(1) and even references 3-ways and 4-ways, but with this new rule it does make it almost imposable to ever do a dead end switch, or even use 14/3 or 12/3 between 3-way or 4-way switches unless you only do neutral pass through which will always put the load being fed to one 3-way and the hot at the other 3-way which limits us to how we can wire them? luckily we are still on the 2008 and it looks like the 2011 will not be adopted which we will jump to the 2014, so it will be a while before we have to worry about this unless I can get this change out of it before we adopt the 2014.

So about the only place you can use 200.7(C)(1) will be if you meet the conditions in 404.2(C)(2)

Or if the switch is controlling a non lighting load.

 

[don_resqcapt19]

This one actually makes sense. Some of the newer switches for lighting control systems require a neutral. This change is an attempt to make sure a neutral is present at lighting switch locations so that in the event one of these type of switches is used, the installer doesn't use the ground wire for the neutral connection.

It wasn't really that the switches had a neutral connection. It was the fact that UL had listed electronic switches that used the EGC as the neutral. UL told the NFPA they would not change the listing standard to require these switches to have a white wire unless the code was changed to require a grounded conductor at the switch locations.

When working on existing systems you need to keep this in mind. The fact that the switches used the EGC as the grounded conductor means that there can be a shock hazard with an open EGC just like there is with an open neutral. The listing did limit the permitted current on the EGC to 0.5mA per device, but there could be a number of devices on the circuit. The 0.5mA should not be enough current to cause a serious shock, but your reaction to the shock could be enough to make you fall off a ladder.

 

[jimport]

This came up on another forum and I would like to hear thoughts on this. Suppose you were to add 3W wiring to an existing SP switch without a neutral. How would the code address this?

 

[jaylectricity]

This actually came into play on a kitchen I just did. The entire kitchen was rewired except for a pendant light location which had the feed, then a switch leg to a couple of 3-ways. The switches were repurposed for a few recessed cans so I ended up running a new switch leg to a new location. I used 14-3, down on black, up on red, white capped off.

During finish she decided she wanted a receptacle for a computer printer inside one of the cabinet drawers. There was just open space for plumbing and other things between the switch on the wall and the back of the cabinet. It was easy to just fish the wire from a box that was already cut into the wall old-work, to the back of the cabinet. Otherwise I might have had to run a whole new circuit.