Mate, if you are in UK - you have 220-240V on one wire and the other one is a connected to neutral when circuit is closed.
I would rather not deal with the electrician who told you that they are 110v each.
Donāt know where you live, but in Belgium it is quite common to have 230v, being supplied with 2 times 115v.
You just treat one wire as live, one as neutral. Shelly 1 works, Sonoff Mini works, everything that needs 230v works, there is just no āneutralā wire, they are both live.
No mate i already mentioned that i live in middle east and yes it is 2 live wire no neutral
Have you tried any smart wall switch ?
If you just use a 240V rated smart switch / dimmer it will be fine. āNeutralā is really just another live but under a different name because we generally join it to earth as a reference point. The smart device will not know this and will work fine as long as there is 240V between the two wires. The same goes for any AC device we use, the āliveā and āneutralā can be swapped over and the device will not know any different.
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sorry to barge in againā¦ If there are only 2 wires in the switch outlet and both are live 110v, then where is the one that goes to the bulb? Could it be that one is 220V and the other is the load carrier line to bulb (So when the switch is off, this line is 0V) ? That doesnāt make senseā¦
When the switch is off there are -110 V running on that wire (in a 230 V regular circuit there would be 0 V). You would then need a switch that interrupts both wires in order to completely cut power at the bulb.
This is because when one live wire is + 110/115 V then the other is -110/115V, thus it would keep a 230 V differential.
Probably it will work with a 230 V, no neutral, smart switch; however, these switches might not be designed with this scenario in mind as they would expect for a very small voltage on the load wire coming from the bulb when that is off whilst it would fare a -110V. One should only look for devices approved by the national regulators.
Simple resistive loads work fine with the +110/-110 V two live wires however sensitive electronics might not:
I second @sparkydave explanation, the two wires are identical in function since they are two poles of the three phase supply, you will just need to choose one as neutral and then do the wiring according to the given diagram you will receive with the smart switch.
Ciao
Claudio
Thanks i will order smart switch and let you guys know about result
Well i think about it and that might work as the smart switch is only forwarding the neutral line from one side to other
Well, I remember when I first experimented with sonoff stuff, I used some plug cords to connect it to the wall plug, and since the plugs in my country can be swapped upside down, Iād say the neutral thing is not an issueā¦I would have noticed it. 
Good luck.
Claudio
Thanks
Have you checked the gif which i put into my first post is it simillar to your case ?
Hi,
in my country (Italy) 99% of the houses have neutral and line wires (the only area I know still have the 2 wires without neutral are some areas in Rome, anyway aside from this, I donāt think your situation is going to be a problem.
I did my testing with sonoffs, if you look at the wiring, the 220V are used to power the sonoff cpu and then the relais in the sonoff cuts one of the wires to switch on and off the light; if you use a sonoff mini you can attach a switch to control it, the wires of the switch are low voltage so the 220V is not involved.
HIH
Claudio
You got to the point. I just wanted to know if the cpu (esp2866) will be able to run while using 220v (2 live wires )
Thanks for everything
I ordered few wall switches from different company with different types i will test and report into this post so other may benefit from this
@CiBi69
Just to let you know guys the sonoff tx t3 uk works Like charm
Thanks for your support
This is an old thread, but Iām bit surprised about the lack of a complete response to the original question. So for people with a similar connection, let me give it go:
Distribution networks use three phases. Usually that is three phase plus a neutral, but in some locations (apparently relatively common in Belgium and Norway) it is simply three phase without a neutral.
For a three phase 230 Volt systems with neutral there is 230 Volt on each of the phases (relative to neutral) and there is 400 Volt between the phases. The consumers are wired between neutral and one of the phases.
For a three phase 230 Volt system without neutral there is 130 Volt on each of the phases and there is 230 Volt between the phases. The consumers are wired between two phases. Usually one phase is blue and the other is brown. But the the blue wire is life and it will shock you!
For a consumer (like a light, an oven, your Shelly or Sonoff or ā¦) it does not make a difference at all. They see a 230 Volt sine wave voltage either way. So they will work as usual.
On a system without neutral, typically you do not need to switch both wires. But be aware that with the switch off one wire is still life, and it will shock you. When switching only one wire some LED lights will not switch off completely due to leak currents. For exterior lights it is strongly recommended (or even mandatory) to switch both wires. A leak on the not switched life wire will trip your differential (GFI).
The three phase without neutral networks where originally used to save a wire (3 instead of 4 conductors) and thus cost. Meanwhile of course those networks run into power limitations (2/3). Not a good orignal decision (opinion).
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