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There is apparently a specific method to wiring an American Light Bulb socket

It's important that we get the right strand to the right screw, so you're going to have one side that's perfectly smooth and the smooth side is going to go to the brass. That's your hot side. The neutral side going to the silver is ribbed. So I'm going to put a little bend in each of the sides here and we're going to screw it down.

I'm trying to write an overhead light fixture which just has two wires coming out of it. Does it matter which one is hot and neutral?

For my light fixture, one wire is red and one wire is blue. For the ceiling they're both white.

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    For the light itself, it does not matter. For safety you will want the hot far away from fingers, so usually the centre post is use for hot, instead of the outside ring of metal close to fingers.
    – crip659
    Feb 15, 2022 at 23:05
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    I think you are just putting colours to wires in the question, instead of stating what is there. In Americas you usually find wire in cable to be black(hot) and white(neutral), not two white wires.
    – crip659
    Feb 15, 2022 at 23:13
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    Two white wires from the ceiling? In the US? Someone screwed up somewhere. You have a bigger problem.
    – longneck
    Feb 15, 2022 at 23:16
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    Is the wire stranded or solid? If stranded, then someone probably used some lamp cord inappropriately and you should find the other end.
    – longneck
    Feb 15, 2022 at 23:55
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    The two wires in the ceiling may both be white simply because they got painted. It's a common practice to spray paint a new house but it's not common to mask the electrical boxes. The wires inside the box end up getting painted too - often in white, since that's a common color for ceilings.
    – Greg Hill
    Feb 16, 2022 at 0:38

2 Answers 2

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Your switch wiring is incorrect. This is the root of the problem.

Your switch is wired with an old-school "switch loop". Power comes into the lamp. A spur goes down to the switch with "always-hot" and back as "switched-hot" for the lamp. Neutral is not present on the switch loop.

Code requires that the white wire be used as the "always-hot". (for several reasons). Which means, up in the lamp, the white switch-loop wire must be connected to the black supply wire.

The previous installer took a shortcut, and just connected black-black, resulting in your not being able to identify the neutral wire.

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The convention in the video is to make hot the center point on the bulb's outlet (what you screw the bulb into). In the graph below this is called the "foot contact". When in a lamp, there is more value because your fingers are some what likely to come into contact with the outlet on the "base" part. If the "base" was hot you'd shock yourself. Not all ceiling fixtures differentiate though. You could hook a meter up to it to find which wire the center point corresponds to for correctness. But it probably doesn't matter.

Parts of the Light Bulb

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    This actually answers the question asked. Harper's answer addresses the potentially serious miswiring part that wasn't explicitly asked.
    – FreeMan
    Feb 16, 2022 at 13:22
  • Which is why more modern fixtures include a ground wire, to guarantee that the fixture itself, including any metal socket parts, remains safe to touch.
    – Carl Witthoft
    Feb 16, 2022 at 16:58

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