Wiring - Touch Switch

[oraclecode 0]

Hi there,

Need advice with regard to wiring a 4 gang 1 way touch switch. I am used to installing the basic rocker/manual switches at home but recently, purchased a touch sensor switch which is proving to be a challenge. I have attached 5 pictures. First pic is of the new touch switch. Second pic is of the diagram provided by the switch manufacturer. Third pic is of the various attempts I have made and the unsuccessful results and finally, pic four and five is of the old switch original wiring. The manufacturer of the new switch thinks the null/neutral is not the null and something else. All advice appreciated. TIA.

 

Edited May 26, 2017 by oraclecode

[Pelect 3]

The blue wire shown is not a neutral wire. If it is, it would be a direct short circuit.

Most homes do not have a neutral wire going to light switches.

It is dangerous to be swap wires so as far as possible, do not attempt to swap wires without first determining the origin of the wire.

Also, the neutral wire, if you manage to pull one in, has to be from the same circuit as the light.

[oraclecode 0]

2 hours ago, Pelect said:

The blue wire shown is not a neutral wire. If it is, it would be a direct short circuit.

Most homes do not have a neutral wire going to light switches.

It is dangerous to be swap wires so as far as possible, do not attempt to swap wires without first determining the origin of the wire.

Also, the neutral wire, if you manage to pull one in, has to be from the same circuit as the light.

Hi Pelect,

Thanks for the reply. Based on the old wiring would you be able to determine the connection type and if it is possible to use the new switch without the neutral? If so, would you be able suggest a work around or maybe advice on how I should go about this project step-by-step short of calling an electrician? Thanks.

[Pelect 3]

From a safety standpoint, it is not worth the risk to attempt to take on this task. So, please get an electrician.

However, from a knowledge point of view, it is good to know what's going on.

First, the new switch will not work without the neutral. The touch switch requires power to operate and that

is supplied by the live and neutral. Also, you can see in the wiring diagram the neutral to the new switch comes from the same lighting circuit. So, when your electrician comes to install, you should see where he gets the neutral to the new switch from. It is not just any neutral, it should be from the same light circuit. Any other neutral might work but it is not the correct way to wire and it could be dangerous.

One word of caution, after you have your electrician pull the neutral wire into the new switch, do not under any circumstances attempt to switch wires around, you could get a nasty short circuit between live and neutral.

Things will become clearer after you see your electrician wired everything up.

[oraclecode 0]

5 hours ago, Pelect said:

From a safety standpoint, it is not worth the risk to attempt to take on this task. So, please get an electrician.

However, from a knowledge point of view, it is good to know what's going on.

First, the new switch will not work without the neutral. The touch switch requires power to operate and that

is supplied by the live and neutral. Also, you can see in the wiring diagram the neutral to the new switch comes from the same lighting circuit. So, when your electrician comes to install, you should see where he gets the neutral to the new switch from. It is not just any neutral, it should be from the same light circuit. Any other neutral might work but it is not the correct way to wire and it could be dangerous.

One word of caution, after you have your electrician pull the neutral wire into the new switch, do not under any circumstances attempt to switch wires around, you could get a nasty short circuit between live and neutral.

Things will become clearer after you see your electrician wired everything up.

Hi Pelect,

Thanks again for the reply. Actually, the switch does work but partially and I have isolated the live wire as well from the rest. In method 2/3/4 of my hand written diagram, 3 switches out of the 4 work normally. I am able to power on and off the lamps but as soon as I use the 4th switch the rest of the switches power off. When I say power off it's not a trip of the ELCB but only all 4 lamps turn off. Nonetheless, I shall heed your sound advice and will engage an electrician soon but in the mean time, any further suggestions much appreciated. Thanks and God bless.

[Pelect 3]

Good you are curious.

Let's use method 3 for the purpose of this discussion.

As I mentioned earlier, you need a neutral wire for the switch to work (fully working).

The touch switch, just like the touch screen of a mobile phone, requires a tiny amount of power so that as soon as you touch, it will sense and turn on the switch.

So how come in method 3, although 'neutral' is not connected, yet switches 2,3 and 4 can still work and why do they switch off as soon as switch 1 is touched?

(remember, your blue neutral is actually not a neutral. The blue wire is connected to something else. You should be able to tell what is being connected to the blue wire because the equipment connected to blue wire will not work if you leave it unconnected just to see what it connects to)

Where did the switch gets it 'neutral' from? Well, it gets it indirectly via wire 1 which is connected to your light/lamp which is connected to the neutral.

if your house is wired correctly and there is no sharing of neutral, then you can try to remove ALL the lights from switch 1 and see if switches 2,3 and 4 will still turn on. 

When all switches are off, the live wire is at 240V. When switches 2,3,4 are closed, they are also at 240V. However, when you close switch 1, it will also be at 240V.

When switch 1 is at 240V, it will be the same electric potential as the live wire. Now switch 1 is no longer at 'neutral' and therefore the entire switch no longer works and lights 2,3,4 will also turn off.

 

[oraclecode 0]

15 hours ago, Pelect said:

Good you are curious.

Let's use method 3 for the purpose of this discussion.

As I mentioned earlier, you need a neutral wire for the switch to work (fully working).

The touch switch, just like the touch screen of a mobile phone, requires a tiny amount of power so that as soon as you touch, it will sense and turn on the switch.

So how come in method 3, although 'neutral' is not connected, yet switches 2,3 and 4 can still work and why do they switch off as soon as switch 1 is touched?

(remember, your blue neutral is actually not a neutral. The blue wire is connected to something else. You should be able to tell what is being connected to the blue wire because the equipment connected to blue wire will not work if you leave it unconnected just to see what it connects to)

Where did the switch gets it 'neutral' from? Well, it gets it indirectly via wire 1 which is connected to your light/lamp which is connected to the neutral.

if your house is wired correctly and there is no sharing of neutral, then you can try to remove ALL the lights from switch 1 and see if switches 2,3 and 4 will still turn on. 

When all switches are off, the live wire is at 240V. When switches 2,3,4 are closed, they are also at 240V. However, when you close switch 1, it will also be at 240V.

When switch 1 is at 240V, it will be the same electric potential as the live wire. Now switch 1 is no longer at 'neutral' and therefore the entire switch no longer works and lights 2,3,4 will also turn off.

 

Hi Pelect,

Thanks again for the clear yet, concise explanation. One would think no more than the basic 2 wire setup for a lamp but this project has opened my eyes to a whole new chapter on how current actually works. I will give your suggestions a try (with proper safety precautions in mind of course) before engaging an electrician in late June, as I will be travelling soon. It has truly been an honour learning from you Pelect. Till then, take care and God bless.