I know I can connect the loose cable from light switch to light fixture, but what do I do with that extra cable coming down to the outlet? Previously this was a fan/light combo with remote that had two loose three conductor (with red wires) cable coming from the light switch to fan installed by previous HO.

enter image description here

  • 1
    Which cable is the power supply? – isherwood Nov 19 '20 at 14:00
  • 1
    You didn't, perchance, take pics of the wiring before you started disassembling things, did you? The wire in question could be supplying power to the light/switch. It could be switched power from the switch to the outlet. What's with all the other cables you've identified at the switch? – FreeMan Nov 19 '20 at 14:05
  • I don't get it, what are we looking at here? My ants tell me you've drawn every single cable with a red wire. That's not likely. Also why remove the /3 (with red) cable? Just because you don't want a fan doesn't mean the next owner doesn't. Rule of thumb: if it's a fan-rated box, run /3 to the box. – Harper - Reinstate Monica Nov 19 '20 at 19:20
  • Where does power come into this setup at, and can you post photos of the insides of the boxes involved? – ThreePhaseEel Nov 20 '20 at 1:47

In electrical we don't just throw wires around.

Rules for cable routing

We start at the service panel and we run a cable from there to the first point-of-use (aka "outlet": that's a switch, receptacle etc., sometimes a lamp but there are special rules required if we do that).

From there (often, not always) we run another cable to another outlet (again: switch, receptacle, etc.)

It's a daisy-chain: from panel to outlet 1 to outlet 2 etc.

It's perfectly OK to have branches/tees: so outlet 3 could have its cable go to outlet 1 (it doesn't need to go to outlet 2).

The cable layout cannot have loops, though. Two separate chains coming from the breaker (or branched off a string) cannot rejoin. If they do, they must be carefully separated in the box. No wires from either side can touch, except the bare safety ground wires.

Your answer depends on the routing of the 2 branches you'd be joining

So now, you must either follow the wires from the switch, and the wires from the outlet... or else make some educated guesses about what they're all about.

In particular, if turning the power on causes both sides to be energized even though they're not connected yet, that means they shouldn't be connected because that would be a loop.

On the other hand, it's possible one side is entirely dead and has no route back to the panel. In that case one side needs to get power from the other. Maybe the old /3 cable carried always-hot for the onward circuit + neutral + switched-hot for the lamp.

If it's a fan-rated box, please run /3 cable to it.

I get you don't want a fan, but many people do. The next buyer of your home might be one of them. Having /3 cable from the fan to the fan-rated box will mean that person doesn't have to bust out drywall later to reinstall what you removed.

If the box is not rated for fans, don't bother; no fan should be there.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.