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Old 01-30-2014, 05:50 PM   #16
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Switch Leg - which is correct?


My confusion is with the terms. Correct me if I'm wrong but I think there is a difference between the terms switch leg (the conductor that goes from the switch up to the light to energize it; power entering the switch) and switched leg.

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Old 01-30-2014, 05:58 PM   #17
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Switch Leg - which is correct?


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Well I just looked up the article, makes no sense to me as to why they want it that way if its identified as power, but what ever makes them happy I guess.
The down on white, back on black keeps you from having two whites at the fixture. Prior editions of the code did not require the white to be reidentified as it was assumed that it was understood the white was hot.
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Old 01-30-2014, 06:19 PM   #18
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Switch Leg - which is correct?


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The down on white, back on black keeps you from having two whites at the fixture. Prior editions of the code did not require the white to be reidentified as it was assumed that it was understood the white was hot.
We were identifying them with black tape around here since the late 70s.
I got my contractors license back in 96 and in all the years of continuing ed classes since then ive never heard it being brought up.
Ive never to this day had an inspector climb up to check the inside of a fixture box to see how it was taped on a rough in/remodel inspection.
Of course I was also told at a young age to never leave a ladder sitting out for an inspector to climb on. Hahaha
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Old 01-30-2014, 11:56 PM   #19
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Switch Leg - which is correct?


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Neither is legal for new work without the neutral in seitch box.
Maybe or maybe not. IMO the main basis for a neutral to show up in switch boxes was primarily aimed at commercial work where devices like occupancy sensors are commonly installed after the fact and when a neutral wasn't present they were using the egc to carry the current to operate the device.. There are a few states that are now including an exception 3 to 404.2 (C). that amends the NEC requirement.

Exception (3) one and two family dwellings


404.2 Switch Connections (C) Switches Controlling Lighting Loads . NCHBA proposed amendment that exempts Residential one-and two-family dwellings from the grounded conductor requirement at lighting switch locations
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Old 01-31-2014, 05:08 AM   #20
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Switch Leg - which is correct?


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Which is correct and why? Code reference if possible.

1) Power comes into light:
- White tied into white of fixture
- Black is tied into the black to the switch
- White from switch tied into black of fixture (taped black at both ends)

2) Power comes into light:
- White tied into white of fixture
- Black is tied into the white to the switch (taped black at both ends)
- Black from switch tied into black of fixture
The switch leg(the conductor returning switched power from the switch to the device) cannot be white. The white conductor of the switch loop must be the conductor taking power to the switch.

#1 is not code-compliant but it will function as electricity does not care what color the insulation is on the conductor.

#2 is code compliant and will function
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Old 01-31-2014, 05:15 AM   #21
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Switch Leg - which is correct?


I know someone will point out that there is no neutral at the switch location so here it is in #2
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Old 01-31-2014, 06:31 AM   #22
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Switch Leg - which is correct?


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The switch leg(the conductor returning switched power from the switch to the device) cannot be white. The white conductor of the switch loop must be the conductor taking power to the switch.

#1 is not code-compliant but it will function as electricity does not care what color the insulation is on the conductor.

#2 is code compliant and will function
On a switch loop like in fig 1, you always feed the switch with the white wire and have the return back to the light black.
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Old 01-31-2014, 10:59 AM   #23
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Switch Leg - which is correct?


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On a switch loop like in fig 1, you always feed the switch with the white wire and have the return back to the light black.
That is not what diagram #1 shows. Diagram #1 shows the switch being fed by the (constant hot)black-wire and the (switched hot)white-wire feeding the light.

It will function but is node code compliant.
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Old 01-31-2014, 11:08 AM   #24
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Switch Leg - which is correct?


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I know someone will point out that there is no neutral at the switch location so here it is in #2
That was the first thing I mentioned.

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Old 01-31-2014, 11:20 AM   #25
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Switch Leg - which is correct?


Thank you all for the information. Should make this post a sticky!

As mentioned before - just changing fixtures and switches - wanted to do it the right way. Simple fixture and simple SP switch.

If I ever do new work, will feed the switch with a 3 wire if power is to the fixture. Obviously no need for a 3-wire if power to the switch first.
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Old 01-31-2014, 11:26 AM   #26
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Switch Leg - which is correct?


What is the reason for the OP to worry about code compliance in an already existing installation? There's no reason to change anything when simply replacing a fixture and/or switch. Code compliance kicks in for NEW installations, not upkeep or maintenance or replacement of an already existing install.
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Old 01-31-2014, 11:37 AM   #27
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Switch Leg - which is correct?


In #2 I personally like to use the red as the switched power. There is no code requirement for that but a personal preference.
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Old 01-31-2014, 12:42 PM   #28
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Switch Leg - which is correct?


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What is the reason for the OP to worry about code compliance in an already existing installation?
Because he is asking and wants to be sure his wiring is correct

Quote:
There's no reason to change anything when simply replacing a fixture and/or switch. Code compliance kicks in for NEW installations, not upkeep or maintenance or replacement of an already existing install
Even if that existing install is not code compliant ...

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