I want to wire this regular switch&outlet receptacle so that the outlet has constant power. This receptacle will replace the switch in the picture.

The current receptacle (where the switch is connected) only has two wires: hot and neutral.

My question: how can I install the switch/outlet combo so that the outlet has constant electricity?

This is a picture of the current receptacle. The switch/outlet combo will replace this switch: enter image description here

  • Confused on what you're trying to do. How about a better explanation and a few pictures of the junction boxes you're dealing with.
    – JACK
    Commented Sep 18, 2021 at 23:06
  • I’ll be editing the question and posting pictures of the existing receptacle.
    – rbhat
    Commented Sep 19, 2021 at 0:04
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    @rbhat If it's hot and neutral connected to the switch, you would create a dead short and trip the circuit breaker every time you turn on the switch.
    – Mark
    Commented Sep 19, 2021 at 15:52
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    @rbhat - No, it's not neutral. It's hot and switched hot.
    – Mark
    Commented Sep 19, 2021 at 17:42
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    That hollow in the wall is called a junction box. There are no receptacles in the photo. You want to add a receptacle, informally called an outlet. As far as what wires switches use, see my answer. Commented Sep 19, 2021 at 18:19

2 Answers 2


This is the metal conduit wiring system

Many people find it annoying only because it is different from what they're used to / most of the youtube videos, but it's actually a marvelous system that does a lot of cool stuff for you.

At the very least, you never need to handle a ground wire. The metal conduit and boxes does it for you. Use "self-grounding" receptacles, those and any switch pick up ground via the mounting screws. Done and dusted!

You use THHN individual wires, which are cheaper and easier to work with than cable. One rule in conduit is "no remarking wires", so you can't re-mark white wires to be hot (and the opposite is never allowed). You need to use native white or gray wires for neutral.

This, however, is a switch loop

That means only 2 wires come down from the light. If you read the below (my original answer), you know that being a switch, those 2 wires must be always-hot and switched-hot.

You need neutral. So in conduit fashion, you will need to "follow the pipe" to see where it goes (expect: the light junction box), and you will need to "pull" a white neutral wire into the pipe. Just one white THHN wire, same size as those already in the pipe. Expect 20 cents a foot, by the foot.

Then you either need a fishing tape, or lots of fidgeting and a little bit of luck, to walk that neutral wire down the pipe.

My own technique for shoving wires (to avoid driving to the other building to get the fishing tape) is to optimize the slack in the existing wires so they can move back and forth 6-12 inches easily. Then push the new wire in until it binds (don't kink it). Then hold the new wire, while pulling the existing wires back for that 6-12" of free play. Then shove all the wires back in that 6-12", and the new wire will now move with the others. Rinse wash repeat, the new wire will slowly ratchet in.

Needless to say, you do all this with the circuit and preferably the building shut off.

How these switches are wired

"Receptacle always on" is how most people want to wire it, and it's built for that. Let's think about what receptacles and switches need.

Besides ground, receptacles need:

  • Always-hot
  • Neutral √

Besides ground, switches need:

  • Always-hot
  • Switched-hot
  • (Switches do not need or use neutral).

Notice how always-hot is common - both switch and receptacle need it? Then the switch has a unique terminal (switched-hot).

As for the neutral, that uses silver screws. There is one. It is directly opposite the taller neutral pin on the receptacle. Not a wild guess that's for neutral, so we can check off neutral.

What is left?

  • You have one brass screw near the switch, and the switch still has a unique terminal unaccounted for. What's unique up there? Switched-hot. Cross that off.

  • Now what's unaccounted for now? Two terminals that both want "always-hot". And what's left on the device? Golly, 2 terminals bridged together. That's convenient!

  • Thanks for the answer. I’ve edited the question.
    – rbhat
    Commented Sep 19, 2021 at 14:17
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    I'm confused. Based on the picture of the (existing) switch, it appears that there is only hot & switched hot in this box (the white tape on the black wire would, I presume, indicate the switched leg). Where would the OP get the neutral for the receptacle? Unless there is a neutral bundle hiding out of view from this angle, I don't think he can do what he's after with his current wiring set up.
    – FreeMan
    Commented Sep 20, 2021 at 13:42
  • @rbhat Ah, you have a different problem which requires a different solution (MUCH easier than the "bust drywall" answer everyone else gets at this point). I've edited too. Commented Sep 20, 2021 at 20:45

That's not the purpose of that tab. You only break that tab if you have two separate isolated circuits on that device. For example, if you had a light you wanted to control on circuit 1 and the receptacle you wanted to put on circuit 3. If you didn't break the tab you'd have a 240v bolted short and the tab would probably likely melt off for you. If the source of the receptacle and the light you are controlling are the same circuit, you wouldn't break that tab as the incoming hot wire for that box would attach to that terminal, the neutral to the silver terminal, and the switch leg to the light on the brass terminal on the other side.

Did I explain that right?

Here's a diagram of how the device is internally connected:

enter image description here

  • Thanks for the explanation. I’ll edit the question so that it’s clearer.
    – rbhat
    Commented Sep 19, 2021 at 0:02
  • I mentioned the part about removing/breaking off the tab because that’s what the youtube video says.
    – rbhat
    Commented Sep 19, 2021 at 0:03
  • DrSparks, not usually. If the OP wanted one outlet switched and the other always powered up (a common application), they are usually run from the same circuit it requires 12/3 or 14/3 from the switch to the outlets, assuming power is supplied at the switch. It's possible to do a switch leg from the outlet to the switch for the one side of the outlet being switched, but in both cases, the tab needs to be broken off for it to work right. It would be quite unusual to have 2 circuits in the same outlet box. Commented Sep 19, 2021 at 0:33
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    @DrSparks oops, I didn't take a close enough look at the device to realize it was an outlet/switch combo. He should just connect the incoming (power) black wire to the black terminal, and the outgoing black wire to the other side of the switch to whatever is being switched. All neutrals (white) should be connected in an appropriate sized wire nut. Commented Sep 19, 2021 at 1:53
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    @rbhat the problem is Youtube selects for people who like to make TV shows, not people who are actually experts at anything. Commented Sep 19, 2021 at 2:15

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