I currently have an armored cable 12/2 with green (ground) leading to a light switch, running outside the wall (simply runs from the light fixture to a surface mounted box where the light switch is).
I will convert this light switch to an outlet light combination.
That means I need a 12/3 cable. Unless for some reason I'm able to use the green as a neutral or hot return.
In case I really need a new cable (12/3):
I assume I can't use NM cable. This is a New York city 13-floors building built in 1965. Correct?
I've found Service Entrance Wire, Portable Power Cord and Armored Cable. It's unclear to me the specific purpose of the SE Wire and Portable Power Cord.
It seems a little hard to find Armored Cable 12/3 – for some reason they are not cheap as 12/2, so that's why I looked into other options.
Any insight is appreciated, thank you!
Best Answer
Portable power cord is for appliances. You know it from every plug-in appliance you have ever owned. It is illegal to use in installed wiring (NEC 400.8).
Service Entrance wire is for connecting services from the transformer to the electric meter in places that are not NYC.
You can use armored cable, FMC flexible metal conduit, EMT hardshell conduit, IMC or Rigid pipe-threaded conduit. Your call. If it is surface mounted, I find EMT generally provides a more elegant installation. The stuff is a learning curve, but it's real nice when done.
As an NYC dweller, there is no reason for you to own any kind of non-metal cable: not NM, not UF, not SE anything, not MH. The only wires to own are AC and THHN.