Use a 3 way WiFi switch for a single light?

Just to say for those who don't know -

These are to us known as two-way switches - three-way in the U.S.
To me they are single pole double throw switches used to provide two-way switching functionality. If we used SPST, DPST. SPDT etc to describe the operation of the individual switch there would be much less semantic confusion!
 
It does sound about right to me :)

View attachment 298199

The circuit diagram shows that the switch should work with those connections.
But if it doesn't, just swap the 'L/Load' and 'wavey line' connections.

...and as above, hopefully the blue wires are neutrals!
That diagram will surely confuse the hell out of any inexperienced person.
The schematic on the left is correct but many Diyers are unable to read those, many will require a physical drawing and I cannot put my hand on my heart and say I understand what the middle and right drawings are trying to inform.
 
...two way it can switch to either output, so could supply a green and a red lamp, three way it can supply three lamps, red, amber and green for example.

We don't normally use the switch that way around, but that's how it got it's name, could also call it a change over switch...
Surely that is exactly how 2 way switching works in the old fashioned method of wiring 2 switches
To me they are single pole double throw switches used to provide two-way switching functionality. If we used SPST, DPST. SPDT etc to describe the operation of the individual switch there would be much less semantic confusion!
I agree with this but I think it would possibly confuse many
...the one marked L/Load is clearly an output,..
I interpret that as L or Load, I know not if I'm right or wrong but Randoms picture appears to show that.


The simple fact is different countries and even different trades within countries have different terminology for what may be a similar product,

yes, SPST = 2 way = 3 way = changeover = 3 pole. Socket = plug = outlet. T&E = 3 core = 3 way = various trade names.
It's only our current international trading policies that create the confusions/discussions such as this.
 
That diagram will surely confuse the hell out of any inexperienced person.
Perhaps I should have been clearer, when I said:
The circuit diagram shows that the switch should work with those connections.
I was simply using the diagram to confirm that the switch should work when wired in the way that the OP suggested.
I.e. it shouldn't matter which way the wires were connected to 'L/Load' or 'wavey line' connections...
There are no other connections in the diagram, so for the switch to operate, it must be able to pick up a Live from any of those terminals.
 
To me they are single pole double throw switches used to provide two-way switching functionality. If we used SPST, DPST. SPDT etc to describe the operation of the individual switch there would be much less semantic confusion!
... and that's exactly the terminology I do use (and have used for well over 50 years!) - except when talking about electrical accessories and associated wiring. In that case the terminology ("1-way" and "2-way" - and "3-way in US!) is so well established/entrenched that I would probably often reduce, rather than increase, clarity by using my 'usual terminology'!

Another advantage of "SPDT" etc. is that it avoids the confusion be often see between "2-way" and "2-gang".

Kind Regards, John
 
From a very early age I've grown up in a variety of different trades with different people and accordingly learnt many different terms, we have not yet mentioned variations (especially in relays) such as make = normally open, break = normally closed, change over, make before break.
...

Another advantage of "SPDT" etc. is that it avoids the confusion be often see between "2-way" and "2-gang".

Kind Regards, John
I can absolutely promise that is we unleashed such terminology on the electrical trade the confusion level would go up through the roof and enquiries on here would do the same.
 
I can absolutely promise that is we unleashed such terminology on the electrical trade the confusion level would go up through the roof and enquiries on here would do the same.
Indeed - that's why I said that I always using the "SPDT" etc. terminology .....
... - except when talking about electrical accessories and associated wiring. In that case the terminology ("1-way" and "2-way" - and "3-way in US!) is so well established/entrenched that I would probably often reduce, rather than increase, clarity by using my 'usual terminology'!

Kind Regards, John
 
I have bought a wall thermostat from Screwfix, and the specs said SPST but in fact it was SPDT and also had a dip switch so N/O could be on rising or falling temperature.

The big question is where does the electronic switch get it's power from? And we simply don't have the answer.

@RandomGrinch diagram
screenshot_20230313-212539_chrome-jpg.298199

Seems to show two electronic switches, which seems pointless, as why would you want two switches for the same light controlled by an app?

However the electronic switches I use have a master and slave set up, we have found the switch KS-641 but not the full instructions for it.

If I had bought the switch, I would either fit it to see if worked, or make a test rig, the advert I found says EU/UK and £45.20 for a pack of 4, think I would one to try one first, but still very cheap for a smart switch, but personally I have used a smart relay, and will admit I was not sure how it would work until I got it and tested it. It actually senses a change in state of switches, does not matter if on or off, but it has turned out a bit hit and miss with the switches, but hey google works every time, so not worried.

Brand Name: Milfra
Model Number: KS-641
Max. Current: 10A
Max. Voltage: 110-250V
European standard
APP: Smart life/Tuya
Support: Amazon alexa/Google home/Google assistant
Working environment: -20°C~75°C
For: commodity houses, villas, hotels, indoor,outdoor
Controlling Distance: No distance limitation
Wireless Standard: IEEE802.11 b/g/n
So reading that, it will also work with voice control, as works with Google home, and Smart life I know works well, only down side is will not work with a PC without an emulator, but big question, is why do you still need two way switching, personally I would use my voice, all it needs is for the name to be easy to remember, hey google turn on landing lights works well for me.
 
The big question is where does the electronic switch get it's power from? And we simply don't have the answer.

@RandomGrinch diagram
screenshot_20230313-212539_chrome-jpg.298199
No we don't know, however the drawing shows 2 schemes, middle shows 'Live wire' and right shows 'Load' for the L/Load terminal although it doesn't show what the 'Box' is supposed to be. However it appears to demonstrate it's able to get its power from any of the 3 (Non 'N') terminals.
 
Last edited:
No we don't know,
I would say we do!

As I said earlier, according to the diagrams, the switch, just wouldn't work (in the 2 ('3') way configuration shown) if they could not pick up the live from the other connections.
 
I would say we do!

As I said earlier, according to the diagrams, the switch, just wouldn't work (in the 2 ('3') way configuration shown) if they could not pick up the live from the other connections.
My comment
...however the drawing shows 2 schemes, middle shows 'Live wire' and right shows 'Load' for the L/Load terminal...
(now edited) surely explains the device is designed to work in any configuration.
 
Back
Top