Lighting circuit with switched neutral?

kwired

Electron manager
Location
NE Nebraska
It was intentional. No doubt in my mind, gained from the experience I’ve had.
Same here.

If OP is not dealing with K &T and wants to "fix" this, might just need to pull the luminaire down and swap where the switch loop is connected to. Presuming there is enough free conductor available to warrant even disturbing anything, otherwise probably just let it be, especially if in a room with non conductive floor coverings or other surfaces.
 

Dsg319

Senior Member
Location
West Virginia
Occupation
Journeyman Electrician
Same here.

If OP is not dealing with K &T and wants to "fix" this, might just need to pull the luminaire down and swap where the switch loop is connected to. Presuming there is enough free conductor available to warrant even disturbing anything, otherwise probably just let it be, especially if in a room with non conductive floor coverings or other surfaces.
It isn’t K&T just old 2-conductor black romex.
And it will be taken out eventually or either replaced.

I had just never came across this before and had left before tearing into and looking at and was just wondering if the theory of it made sense.
 
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James L

Senior Member
Location
Kansas Cty, Mo, USA
Occupation
Electrician
It isn’t K&T just old 2-conductor black romex.
And it will be taken out eventually or either replaced.

I had just never came across this before and had left before tearing into and looking at and was just wondering if the theory of it made sense.
My house is black ungrounded Romex, too.
All the lighting was wired with switched neutrals
 
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kwired

Electron manager
Location
NE Nebraska
It isn’t K&T just old 2-conductor black romex.
And it will be taken out eventually or either replaced.

I had just never came across this before and had left before tearing into and looking at and was just wondering if the theory of it made sense.
Other than you might find same or very similar conductor insulation no. The romex will have both conductors of circuit and both conductors of switch loops routed together as they are within the cable sheath, just like you commonly see today. The K & T those conductors maybe run within a few inches to ~16 inches apart (particularly when one on each side of a stud bay) most the time, but they do end up much further apart at times, especially some switch loop situations, and of course no outer covering like the romex has.

What is similar is no EGC.

Any circuit old or new will behave similar if you switch the grounded conductor instead of the ungrounded conductor.
You also can run into similar confusion with voltage readings if switching only one pole of a 208-240 or 480 volt load.
 
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