Neutral for switch for Half-Hot

[George Stolz]

Does 404.2(C) require a neutral for a switch controlling a half hot for a plug-in table lamp (assuming that the exceptions do not apply for a given installation)?

The textbook says "yes", and I have said "yes" in the past, since 404.2(C) does not reference "luminaires", but "lighting loads." 210.70 permits switched receptacles in lieu of luminaires. That indicates the switched receptacles are for lighting loads.

However, 404.14 still (rightfully) forbids dimmer switches from being installed to control receptacles.

My main bone to pick with this is that the textbook shows a 14-4 NM being used as travelers between a set of threeways in a bedroom, in order to carry a full-time hot along for the ride. There is also a ceiling fan with light kit shown in the room, so these switched receptacles are not "code-required switched receptacles in lieu of lighting outlets", they are simply switched receptacles.

Bearing in mind I am teaching first years here, I am inclined to recant my earlier grumblings about the use of 14-4 wire in the text and say that the 14-4 is required. I have already made it clear that a neutral is not required for other loads, such as disposals and so on.

What would you do?

 

[Dennis Alwon]

A dimmer switch is only one reason for the neutral req. the other could be an occupancy sensor. Since the switched outlet is a lighting outlet then IMO the neutral needs to be present at the switch location. BTW there are special receptacles made that are compliant when used with dimmers.

Is a neutral needed at a door jamb switch? Any ahj that enforces that needs his head examined.

 

[ActionDave]

Is a neutral needed at a door jamb switch?

Yes it does.

Any ahj that enforces that needs his head examined.

No, the people that write the code do.

 

[jumper]

.

Is a neutral needed at a door jamb switch? Any ahj that enforces that needs his head examined.

IIRC, some fella got a 2014 proposal accepted that exempted door jamb switches.

Lemme see, now what was his name.......

 

[Dennis Alwon]

IIRC, some fella got a 2014 proposal accepted that exempted door jamb switches.

Lemme see, now what was his name.......

Yep-- that be me.... but you have to wait....:lol:

 

[George Stolz]

No, the people that write the code do.

I agree. :sigh:

Well, I will teach then that the best method for threewaying a switched outlet is to use 4-wire, as code requires. This section just stinks.

Who knows, maybe it can get deleted in the 2017; perhaps the UL will change their listing habits and make this section (more) unnecessary.

 

[Dennis Alwon]

I have never used 4 wire. I fed one side and switch leg from the other. Neutral is fed thru even in 4 way switches.

 

[don_resqcapt19]

...Who knows, maybe it can get deleted in the 2017; perhaps the UL will change their listing habits and make this section (more) unnecessary.

I don't see how UL could make a change to get rid of the rule that requires a grounded conductor at light switch locations. The only reason for this rule was so that UL would stop letting the manufacturers of electronic switches use the EGC as a grounded conductor.

 

[George Stolz]

I have never used 4 wire. I fed one side and switch leg from the other. Neutral is fed thru even in 4 way switches.

This is a threeway for a half hot. It would be impossible without 4-wire (liberties with 3-wire and 2-wire and 300.3 notwithstanding.)

 

[George Stolz]

I don't see how UL could make a change to get rid of the rule that requires a grounded conductor at light switch locations. The only reason for this rule was so that UL would stop letting the manufacturers of electronic switches use the EGC as a grounded conductor.

That was the idea; but if UL simply refused to list a device that intentionally used the EGC as a neutral, the rule could be deleted and we would have the option to use switches with neutral tails or not - same as it always was.

I have never encountered a fancy switch with integral neutral with the white tied to the ground in the field; have you?

Generally, if there is a neutral required and no neutral present, then the switch is swapped for a compatible one. It's pretty rare for one to decide to tie the white to the EGC in the box, IMO.

 

[don_resqcapt19]

...I have never encountered a fancy switch with integral neutral with the white tied to the ground in the field; have you? ...

The switches in question do not have white wires that you tie to ground in the field. They have green wires that are used internally as white wires and I have installed a number of them.

UL told the NFPA that they would not change their standard to prohibit the use of the EGC as a grounded conductor unless the code was changed to make a grounded conductor available at the switch location.

 

[al hildenbrand]

This is a threeway for a half hot. It would be impossible without 4-wire (liberties with 3-wire and 2-wire and 300.3 notwithstanding.)

So grabbing a pair of two conductor with ground NM cables and using nonmetallic boxes is a problem with "first years"? They are taking first imprints. . . "always wire in ways that result in neutrals in switch boxes."

The nuances come next year.

 

[Dennis Alwon]

This is a threeway for a half hot. It would be impossible without 4-wire (liberties with 3-wire and 2-wire and 300.3 notwithstanding.)

Not impossible. You feed the receptacle separately and the half hot can be fed from the switches. Break both neutral and hot tabs.

 

[George Stolz]

The switches in question do not have white wires that you tie to ground in the field. They have green wires that are used internally as white wires and I have installed a number of them.

As have I, I understand what you're saying.

I am saying UL should never have listed them in the first place. 250.6 and so on.

UL told the NFPA that they would not change their standard to prohibit the use of the EGC as a grounded conductor unless the code was changed to make a grounded conductor available at the switch location.

That is a ridiculous compromise to have made. UL was listing devices in conflict with the code, so NFPA gives in and changes the code 100 years after it's inception as a compromise - despite 100 years worth of structures out there that do not comply, and a pittance of new structures that would make use of the change. It sounds so illogical it must have been the NFPA's idea.

:rant:

 

[George Stolz]

Not impossible. You feed the receptacle separately and the half hot can be fed from the switches. Break both neutral and hot tabs.

And jam four 14-2s in 1098s around a room filled with half hots?

 

[George Stolz]

So grabbing a pair of two conductor with ground NM cables and using nonmetallic boxes is a problem with "first years"? They are taking first imprints. . . "always wire in ways that result in neutrals in switch boxes."

The nuances come next year.

Well, we're "wiring" with 4-wire where "necessary".

 

[al hildenbrand]

Well, we're "wiring" with 4-wire where "necessary".

I started stocking 4-wire NM in #12 & #14 quite a while ago, although I don't keep it on the truck, except for what I'm transporting for a specific install. There's nothing like it. The blue conductor adds a level of class to the finished job.

Perhaps the tip for the first years is handled in a quick overview of the "special-ness" of actually having 4-wire to work with in class, and then touching on the idea of re-identifying cable conductors with tape, etc, because pre-2011 NEC switching installations may require it, and also 4-wire may not be available at future job sites.

 

[dicklaxt]

I sure would like to know what a "Half Hot" is.I was hoping someone else would ask so I wouldn't look stupid

dick

 

[Dennis Alwon]

I sure would like to know what a "Half Hot" is.I was hoping someone else would ask so I wouldn't look stupid

dick

Switching half the receptacle while the other half is constant hot.

 

[Dennis Alwon]

And jam four 14-2s in 1098s around a room filled with half hots?

sorry I was thinking one half -switched recptacle