LED dimly lit, or glowing, even when switched off demo (remastered)

Hi this is a video on a strangeaberration which you can find sometimes with LEDs.

This is an LED 8 watt BonLuxdimmable LED.

It is unusual in the sense that it doesn't have any sort ofcircuitry there or least that I can see inside it such as smoothing cap orresistor network with various things that you often do see in LEDs and you'llnotice that even in the off position it's lit, dimly but still lit.

Now I'llswitch on just so you can see what it's like when it's switched on thestrobing that you see is because the light itself does actually strobeand if we switch it back you can see that again it's dimly lit.

Now if I showyou against another 8 watt LED which is the MiniSun this is a non-dimmable you can see in the off position it's not lit at all.

In the on position it's again it's 8 watt LED there's no strobing at allon this I quite like these and I recommend thembut anyway the reason what I wanted to show this is because of this particularaberration which is caused by the configuration of the lighting.

Now let meput the stuff into the off and we'll just take a look at the ceiling rose itself.

Now this is the ceiling rose and this is a typical British ceiling rose what itlooks like but it's been wire strangely and the reason for that is because thisis normally configured for switched live.

So live is switched and the bulb ispermanently connected to the neutral side of things as the normal configurationthat you expect in the UK .

Now what I've done is I changed that set up because Iwanted to have a switch neutral, sometimes you get this strangeeffect and essentially what it's like is if you have an electrician screwdriversuch as this and I was to put that onto the live, you can see that LED that's notan LED it's a neon and it's lighting when I touch the back of it and that'sbecause the live wire is capacitively couple through the the electrician's screwdriver and it's essentially radiating energy from me from my bodyand that's why it's lit.

Now in this particular case you can see that the thelive wire here which is on the brown is connected to the pendant itself.

What wehave here is the the live wire is actually going into the pendant so it'spermanently connected to one side of the LED and the other side is going throughthis red wire here, which is one side of the switch it's coming back through theblack wire which is the other side of the switch and it's looped in thisparticular orange wire into the neutral.

So effectively what's happening is it'sswitching the neutral, so that the neutral is going to the switch and it'sbeing switched at that point.

So essentially we have the live connectedto this but in the off position the energy essentially would mean that thewhole neutral side this blue wire up and to the point where it reaches the breakin the switch itself will go live and that, a bit like the electrician'sscrewdriver, is like me touching the end of it and it's radiating and it'sradiating within the actual switch conduits network itself and that isallowing just enough energy to actually light a bulb.

Now if I had an ordinarylight bulb in there the because the tungsten requires so much more energy toshow any sort of lighting basically you'd see nothing and in this particularcase where you have a network here, which builds a bit of a barrier for theelectricity as such which is allowing it to glow and also there's a capacitor inthere which I believe is acting like a shunt like a bypass.

So it's never givento the point where it has enough voltage to actually light it even dimly.

I'lltake that out now what I want to show is, when I changethis so it's then going to switched live that you will see a difference so let mejust put this on pause.




and we're back so now I've changed it.

So it's going fromthe neutral line is connected to one side of the bulb.

The other side is going tothe black wire, which is one side of the switch.

The other side of the switchwhich is coming back, is a red wire and just a little bit more of a close-up ofthat so you can see how it's changed.

So the brown wire goes from this goes intothe black wire, which is the switch, comes back to the blue which is the permanentconnection to the mains neutral the other side, is the red wire which goesthrough this orange loop into the mains which is the brown wire here on thatside there.

So essentially this is what's called a switched live and in thisparticular case, which I had earlier which was glowing, and as you can see inthe off position, it is no longer glowing.

So you can see the bulb is no longer glowingso that's switched on as you can see it's strobing like it was before andswitched off nothing, whilst before it was glowing and this is the mini Sunagain I switch that on you can see that it's actually normally they're bothacting exactly the same way and the way I would expect it to have so hopefullythis shows the aberration and explains the aberration.

Thank you very much forwatching and until next time.

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