electricallightingswitch
I have a free standing pantry with an outlet and a light switch on it.
light switch works just fine. The problem is when I use the outlet I.E. plug the vacuum or anything else into it and power it on, the light that is controlled by the switch comes on.
Any help would be appreciated.
IMHO, it could be one of three things:
1) A feature of the lights. Some lights might have a "nightlight" feature.
2) Electromagnetic interference (EMI). Depending on how much electricity the lights require, and how dim they are, this might be possible. Especially if it's a half switched receptacle that was wired with a single 14-3 wire and the constant hot is powering the other half of the plug and something is plugged into it and drawing power while the switch is off... but I guess it could feasibly happen if the wires were just run next to other wires that are constantly powering something else. If this is the case, there's nothing wrong - it's just annoying
3) There's a small arc fault. I don't know how to verify this for sure because it might look just like EMI. These can go undetected for years and have the potential to start a fire. I've opened up walls before and found that half the 2x4 was burned away. I suggest doing whatever is cheapest and easiest first just in case the fault is in something easily replaceable (like replacing the switch and/or receptacle, or checking the receptacle with a volt meter). Or you could start with this just to make sure it's wired correctly (although I don't see how that could be the problem). But if you can't find it easily right away with those things, I'd install an AFCI on that circuit... and if that continues to trip, you know you have a serious problem, and it's time to call a professional electrician with equipment that can trace the wire and/or find the location of the fault.
With pilot switches, you can get any combination you want, simply by wiring it differently.
Top: the pilot is on when the switch/light is on.
Middle: The pilot is on always.
Bottom: The pilot is on when the switch/light is off. However, this works by leaking power through the bulb. So it only works if the bulb is not burned out, and is able to tolerate this leakage (incandescents can for sure.)
In these drawings, ground is omitted for clarity, neutral is white, always-hot is black, and switched-hot is red for clarity. The internal arrangement of the pilot switch is shown, so you can see why it works.
Note also the "upper right terminal" in my drawings. See how it serves both the switch and the light. In some pilot switches, this actually comes out to two screws on the side of the pilot switch with this side considered "common". In that case, the "sides" on your switch won't be in the same places, not that they ever are.
Best Answer
I would alter your thinking. The light switch and the socket are not "just fine."
Odds are your switch or your socket (or both) somehow have the ground / return wires incorrectly wired. So either the switch routes the return into the ground when closed or worse. The plug is likely on the same circuit and completing the circuit for the switch due to the miswiring. This could be done a number of ways, some which involve the misconnected ground feeding electricity into the plugged in device, returning through the return (or some other odd but similar arrangement).
I'd have an electrician go over the switch, the light, and the socket. If any of these items were rewired, odds are there was an undetected issue, as they didn't plug something into the socket and test the light in conjunction (and the device seemed to work).