Electrical – Add combo (switch and outlet) with only two wires out of wall for the current light)

electricallightingswitchwiring

I probably have this diagram for my project. Or problem.

Facts:

a) only 2 wires out of wall, B & W;

b) switch ON, lights ON

Ceiling electrical box:

One black and one white connects to the ceiling light fixture.
enter image description here
enter image description here

Project: I need to add a combo switch/outlet

UPDATE after suggestions

Grey= Neutral
Is this right?
If it is, it seems to me receptacle will be ON at all times, right?

enter image description here

Best Answer

Three options

Run a new /3 cable

You either replace the existing cable with /3 cable (which is now required in new work), in which case your three wires are:

  • always-hot (traditionally black, often white-with-black-tape, sometimes white)
  • switched-hot (ideally red, sometimes black, often white-black-tape, often white)
  • neutral (always white)

And these three go to the lamp/receptacle combo, always-hot to the common bar, switched-hot to the switch side, and neutral to the receptacle side.

Run a whole separate /2 cable

In a perfect world you source that from another location which is not a lighting circuit, but does provide GFCI, AFCI or whatever other protection you need owing to that location. But if you need to, you can get this from the lighting box, if Code allows this, e.g. In bathrooms it might not. In this case your two new wires are:

  • always-hot (black usually)
  • neutral (always white)

And you break the tab off the hot side of the switch/recep combo. These two new wires go to the receptacle side, neutral to the taller pin side. The two existing wires go to the switch side only. You must break off the tab.

Smart switches

Talking something like Insteon.

In this case, rewire so all black wires are always-hot, and all white wires are in fact neutral. Always-hot and neutral go to your smart switch w/ receptacle.

Up in the lamp, the switched-hot to the lamp is now dangling, as it has nowhere to connect to, there are no switched-hot wires up there, you killed them.

So you get a smart-switch module, that connects to always-hot and neutral. It also has a "Load" line which goes to switched-hot, and that's where the lamp's switched-hot wire goes.

Now if you leave the light on, you can turn it off with your phone. From Kazakhstan.

Related Topic