3 WAY Switching

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I have three individual switches for the light on the 1st floor landing of my house and I think they are wired in correctly as everything works as it should apart from a single combination where the LED stays dim.

I am not sure why however when this has happened before the neutrals were the wrong way around however I am not sure if this is the case here or if its working as it should do...

I have done some testing and listed all the outcomes below:

Switch 1 Switch 2 Switch 3 Outcome
ON ON ON Light ON
ON OFF ON Light OFF
ON ON OFF Light OFF
ON OFF OFF Light ON
OFF ON ON Light DIM
OFF OFF ON Light ON
OFF ON OFF Light ON
OFF OFF OFF Light OFF


Does anyone know if this is what should happen or there is something wrong somewhere?

Many Thanks

James
 
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Something wrong yes.

But hard to say exactly what at this stage.

Photos of each switch and the light may help, but in all honesty an electrician on site is really the way to go here.
 
As you probably realise, all of the outcomes you describe are correct, other than that the "OFF ON ON" should result in the light being off, not 'dim'

As bernard has said, faint glowing of LEDs when they are meant to be off is a common problem (for the reason he describes) and when one has complex switch such as you do, it's not unusual for the problem to arise only with one, or some, of the combinations of switch positions which should result in the light being off. When you say 'dim', do you mean 'very dim'/glimmering (which is what one would normally see with this phenomenon), or just a bit less bright than when properly on?

Kind Regards, John
 
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The switched sequence appears to be correct but the "dim" condition should be an "off". How dim is dim and what type of lamp is fitted.

As previously stated there could be sufficient capacitive coupling to allow sufficient current to illuminate a cfl or LED lamp but certainly not an incandescent (tungsten or halogen) one. So, if the lamp is an incandescent one then you have a problem

When displaying logic tables such as yours it's easier to interpret sequence if you only make one change at a time, rather than 2 as you have shown in several places.

edit : darn it beaten by JW2 whilst writing.
 
Thanks for your replies. Its very strange though that it's only when two switches are on and one is off...

I have this with two switches on another led light and it doesn't do this which is why I was confused...

I will see if I can get some pics and upload them of the switches initially And then get the light off and see what I can see from there and get some pics.

Thanks

James
 
John sorry I just posted and didn't see your response. Yes it's very dim indeed it just lights up ever so slightly. And yes it's an led not a halogen light.

So does this mean that it's just "normal" in complex switching? Although thinking about it the other one I have is only two switches opposed to it being three which I presume has Something to do with it as its less complex...

Thanks

James
 
John sorry I just posted and didn't see your response. Yes it's very dim indeed it just lights up ever so slightly. And yes it's an led not a halogen light.
In that case, it is very probably due to the phenomenon that bernard mentioned.
So does this mean that it's just "normal" in complex switching?
Common, rather than 'normal', and not necessarily with complex switching - it can happen with just a single on-off switch. However, as I said, when there is complex switching, it's not unusual for it to only happen with one (or some) of the combinations of switch positions which should result in the light being off.

There is a solution to the problem which nearly always works - namely fitting a 'suppressor' across the lamp. If you look at the discussion that bernard linked to, you'll probably find details - if not, come back and ask!

Kind Regards, John
 
Thanks so if I understand correct from bernards post I purchase the suppressor and on the ceiling rose put it between the neutral and live? So the live and neutral go through this and it takes out the capacitance issue?

Would this work with a lamp holder? As I have a lamp holder on the hall....

Thanks

James
 
Thanks so if I understand correct from bernards post I purchase the suppressor and on the ceiling rose put it between the neutral and live? So the live and neutral go through this and it takes out the capacitance issue? Would this work with a lamp holder? As I have a lamp holder on the hall....
Yes, you just connect it between the (switched) live and neutral going to the lamp - at the lamp holder or wherever. It doesn't make the 'capacitance issue' go away, but it means that the tiny current due to that issue gets bypassed through the suppressor, rather than going through the LED and producing that dim glow.

Kind Regards, John
 
Ok that's brilliant I Will get one and add it to the lap holder. So it goes in the same place with the wires just to be clear?

Thanks

James
 
Ok that's brilliant I Will get one and add it to the lap holder. So it goes in the same place with the wires just to be clear?
Yes, just connect it to the same place as the two (L & N) connections to the lamp, obviously making sure that the wires to suppressor and to lamp are both properly secured by the terminal screw. It does not matter which way around you connect the suppressor.

We usually say that the suppressor works in about 99% of cases like this. Please let us know whether you prove to be one of those 99% or one of the very unlucky other 1%!

Kind Regards, John
 
Thank you I just wanted confirmation ☺ I will do as soon as I have done it. Knowing my luck it won't work however as its one specific combination I could live with it if needed it's just nice if everything works as it should.

Thanks for your help as always greatly appreciated.

Many thanks

James
 
Thank you I just wanted confirmation ☺ I will do as soon as I have done it. Knowing my luck it won't work however as its one specific combination I could live with it if needed it's just nice if everything works as it should. Thanks for your help as always greatly appreciated.
You're welcome. I hope that it works for you!

Kind Regards, John
 

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