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I have a 14-2 cable at the light switch in my room. White is my hot, black is my switch leg. At my light I have some older cloth braided sheathed wire. This also is a two wire nothing is labeled.

Assuming my cable from my switch splices in a box somewhere and then transitions to this cloth braided wire to my light, how was this light not running with a neutral? Could the neutral be picked up somewhere else maybe on a receptacle? The same two wires (cloth braided) at my light are the same two at my switch cable. I ran continuity and they for sure are the same two. To my understanding there was no neutral, correct? Trying to figure this out and it’s killing me cause i can’t find the box where the wires transition.

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  • Welcome to Stack Exchange. "how was this light not running with a neutral?" Do you mean, "how is this light running without a neutral?" If so, please edit your question - it's not clear. Was/is there a light currently connected to the braided wire? Is it working? It would help to have pictures of the inside of both boxes.
    – HoneyDo
    Sep 4 '20 at 16:08
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    I have a feeling that you're misunderstanding how a typical switch loop works. The second cable in the light box is probably the source, and there wouldn't be a neutral at the switch--just the hot passing by. Is this wrong somehow?
    – isherwood
    Sep 4 '20 at 16:21
  • Are you saying there's only one cable, with two wires, entering the light fixture, and the same situation at the switch? In that case, yes, you definitely have another box somewhere. If there's no blank cover plates in the room, it could be in the attic or crawlspace. Code requires it be accessible, but not necessarily easy to find.
    – Nate S.
    Sep 4 '20 at 16:30
  • Are there more than one lights that this switch activates the hot and neutral may be in a different junction box a light will not work without a neutral. Note all the hot’s are in parallel on that circuit with the power off and a standard lightbulb in everything will have continuity and spear to be connected.
    – Ed Beal
    Sep 4 '20 at 19:47
  • Can you post photos of the insides of the boxes involved please? Sep 5 '20 at 3:29
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Other loads are getting you

Switched-hot@switch and switched-hot@lamp will read continuity because they actually are the same wire.

However, always-hot@switch and neutral@lamp will also read continuity because of other loads.

Presumably this is NOT a dedicated circuit just for that lamp. So that means the circuit visits other lamps, other hardwired loads, other receptacles etc. If any of them are switched on, they create a relatively low resistance between always-hot and neutral.

So even though you have the circuit turned off, any loads attempting to draw current will create a continuity between always-hot and neutral.

However, if you use a proper voltmeter, the resistance will be detectable. (mind you with incandescent lights and some digital power supplies, it can be lower than during operation; that's what inrush current is all about.) For instance a heater drawing 12A will have -- let's see E=IR

 120V = 12A x R 

R is 10, so 10 ohms. That's quite a low resistance value, so a continuity detector would read continuity, but a real ohmmeter should show a true number.

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