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snnet
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  #2532823 1-Aug-2020 17:44
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I have had it on jobs especially where the circuit is switched in multiple positions for the LED lamp to glow - as I said earlier a load correction device fixes this




richms
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  #2532837 1-Aug-2020 19:16
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Rikkitic:

 

It is not. The glowing in this case is a bug, not a feature. It doesn't happen with other bulb types, only LED. It looks to be an induction effect.

 

 

Capacitive, not induction.

 

If you have the sensor connected by 3 core wire then there is often enough capacitance between the wires to cause this to happen on cheap LED lamps, and some more expensive ones too.

 

Or if they put a capacitor across the output of the motion sensor to supress interference when the contacts arc at turn off, that will pass enough current too.

 

Swapping one LED out for something with a real power supply in it, or putting a resitive or inductive load on the same output will solve it. A common thing with LED downlight swaps is to leave one of the old magnetic transformers connected so that there is a load that will drop the voltage down to below what the LEDs will light at, but not take appreciable power when switched on.





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neb
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  #2533063 2-Aug-2020 13:36
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Rikkitic:

One is in a motion detector in a hallway. It switches on when someone gets up at night to use the bathroom. But it doesn’t switch completely off. Instead, it glows all the time and the glow is actually fairly bright.

 

 

Could they be using the LEDs as droppers to provide power to the motion-detector circuit? That's a clever (in the sense of pennypinching) design, but also means there's nothing you can do to fix it.



sqishy
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  #2533070 2-Aug-2020 13:51
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gregmcc:

 

sqishy:

 

If it has motion and a normal on/off wall switch sounds like your live is gong to the bulb from the switch and the wall switch is switching negative. Often the live on the bulb causes a low glow.

 

 

@sqishy - what is your electrical background? The above statement is very wrong, there is no "negative", there may be a neutral which should not be switched, but switching this instead of the phase would not cause this to happen.

 

 

 

BTW 30+ years in the electrical industry, registered Electrical Inspector so I think I have a good background to give advice here that can be relied upon.

 

 

I question your back ground, negative is an old term for neutral. On LED lights many old house some dodgy people ran power and switched neutral. This sometimes causes leakage and the LEDs would flash or come on. I'm surprised you don't know this.


gregmcc
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  #2533138 2-Aug-2020 15:34
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sqishy:

 

 

 

 

 

I question your back ground, negative is an old term for neutral. On LED lights many old house some dodgy people ran power and switched neutral. This sometimes causes leakage and the LEDs would flash or come on. I'm surprised you don't know this.

 

 

@sqishy - Question away, I don't mind people asking further questions about my electrical background, so what is your question? Oh please let me and others following this what your electrical background is.

 

Negative refers to the (-) side of a DC power supply, this whole thread revolves around a motion sensor that takes a standard 230VAC light bulb, in this case an LED one.

 

Negative has *never* been a term for neutral.

 

I did notice that you made some comments on another topic regarding hot water elements, with advice that failed to include other factors which if followed could have easily resulted in a fire, I did advise the OP to ignore your advice. As far as " dodgy people ran power and switched neutral" switching the phase or neutral in this case would make no difference, it is simply the long run on cable between the switch and the bulb and induced currents that causes the LED bulb to glow or flicker, without more details I would not think that this is the case.

 

 


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