boxsterguy t1_j1f8diz wrote on December 23, 2022 at 9:45 PM

Reply to comment by created4this in Can I install this single pole switch in place of the dimmer switch that was here? by Affectionate_Cronut

Looks like a shittily wired box. Either there's a line and neutral with no load (in which case, you would wire a receptacle there, not a switch), or it's an old school no-neutral lights-only loop and they used white for load. Both are wrong, but given they're wiring a switch one would have to assume it's the latter and would still work even with the colors being wrong.

Switching line and neutral would be pretty stupid.

yeah_its_mike t1_j1fg71i wrote on December 23, 2022 at 10:46 PM

Yerp. Sometimes still done today. It's not up to code as we need a neutral in the switch box.(Now) Black feed white switch loop. Neutral already existing at the light connected to another point in the same circuit (hopefully).

Edit: You can't always go off color of wires. I wire 3 and 4 way switches using white wire.(14-3 with ground) I identify with tape. Some electricians don't.

boxsterguy t1_j1fi8z0 wrote on December 23, 2022 at 11:02 PM

Worst case scenario, voltage detectors (or your fingers) don't lie. Turn on the power, check the wires, see what's energized when the switch is off.

yeah_its_mike t1_j1fj6xu wrote on December 23, 2022 at 11:09 PM

Meter, fingers, apprentice, metal grounded box whatever is closest. If it's early AM fingers is the best for a wakeup.

created4this t1_j1fcv8m wrote on December 23, 2022 at 10:19 PM

The wiring is line in/line out which is the two twisted lives (black) as well as a switched live out (black alone).

The whites are the neutrals.

Wiring a switch to bridge between live and neutral (as it would be if they copied the pictures) is a problem

boxsterguy t1_j1fe3ab wrote on December 23, 2022 at 10:29 PM

I was referring to the linked article, not OP's picture. As I assumed you were doing, too, when you said, "Not those colors".

[deleted] t1_j1ft3ov wrote on December 24, 2022 at 12:27 AM

[deleted]

created4this t1_j1hdbbb wrote on December 24, 2022 at 10:24 AM

You can tell how it’s wired by the fact the original dimmer was between two blacks.

I’m not saying to assume that white is neutral for the purpose of fitting a smart switch here, I’m saying assume white is neutral so you don’t wire a switch to short it to live. The new switch needs to be wired like the old dimmer, not like the picture in the link at the start of this sub thread.