Led retro trims glow dimly when switched off

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tortuga said:
McLintock did:

And thats interesting I wonder why that would make a difference electrically? (Switched neutrals have not been allowed since the early 1920's)
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If there are other loads on the neutral, there will be current on the neutral to the lights in question.
(We're not talking proper install here, we're troubleshooting, LOL!)
 
readydave8 said:
of course if no one mentioned already, breaking the neutral instead of hot at switch will cause this
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tortuga said:
McLintock did:
McLintock said:
Had this issue a few years ago at a farm, he replaced some high pressure sodium with LED lights. He turned the switch and the lights glowed. I went out and found they had the neutral switched
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And that's interesting I wonder why that would make a difference electrically? (Switched neutrals have not been allowed since the early 1920's)
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I'm thinking this effect could be caused by the capacitance from the switched conductor to the EGC.
If the hot is switched and the switch is off, then the load consisting of the light in series with the switched-hot to EGC capacitance will be connected between the neutral and the EGC. And so negligible current will flow through the light in this case because there should be very little voltage between the neutral and EGC.
But if the neutral is switched and the switch is off, then the load consisting of the light in series with the switched-neutral to EGC capacitance will be connected between the unswitched hot and the EGC. And so a non-negligible current could flow through the light, depending on how much capacitance there is.
 
synchro said:
I'm thinking this effect could be caused by the capacitance from the switched conductor to the EGC.
If the hot is switched and the switch is off, then the load consisting of the light in series with the switched-hot to EGC capacitance will be connected between the neutral and the EGC. And so negligible current will flow through the light in this case because there should be very little voltage between the neutral and EGC.
But if the neutral is switched and the switch is off, then the load consisting of the light in series with the switched-neutral to EGC capacitance will be connected between the unswitched hot and the EGC. And so a non-negligible current could flow through the light, depending on how much capacitance there is.
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Interesting, so an other wise correct wiring system, just move the switch to the neutral side and there would be a large capacitance. And its a dimmer so probably not a real switch off, more like a transistor.
 
Little Bill said:
Make sure the neutral is for the lights. The MLC is small, about 1" sq and maybe 1/2" thick. You just connect it between hot and neutral. It can be in the switch box, in the light, or anywhere along the circuit that is accessible.
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Good stuff guys! Switched neutrals can effect a circuit in ways I never would have thought!

Little Bill, the neutral must be the one associated with the lights in question, the load cap cannot be wired into the neutral elsewhere on the same circuit? Like I mentioned, it's a dead end switch leg controlling the lights, but it shares a two gang with another dimmer, in which contains a neutral that I believe is from the same circuit. So it would be cool if I could feed this cap with the feed that's coming down from the light, and wire it into the nearby neutral/grounded conductor.
 
mark32 said:
Good stuff guys! Switched neutrals can effect a circuit in ways I never would have thought!

Little Bill, the neutral must be the one associated with the lights in question, the load cap cannot be wired into the neutral elsewhere on the same circuit? Like I mentioned, it's a dead end switch leg controlling the lights, but it shares a two gang with another dimmer, in which contains a neutral that I believe is from the same circuit. So it would be cool if I could feed this cap with the feed that's coming down from the light, and wire it into the nearby neutral/grounded conductor.
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Anywhere in the same circuit.
 
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