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Hello from cold Russia.

1)Don't use the grounding wire to connect N pin on your wall switch. If you don't want to win Darwin award. 

Look at the first picture.

2)Use capasitors to connect the switch and the bulb. 

Look at the second picture.

C1 - Capacity. Metal-film capacitor for 400 volts.

It works as a "quenching capacitor" or "resistance". In order for the "part of the current" to remain on the switch and feed it, in the switched on position of the key.

C2 - Capacity. Metal-film capacitor for 400 volts. 

Works as a "bypass" resistor. Serves to ensure that energy-saving gas-discharge or LED lamps do not blink (from the current passing through them supplying the switch) in the off position of the key.

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2 people have this question

I appreciate your effort to share the NO NEUTRAL wire solution.

Can you re upload the diagram with english ?

The capasitor given in 1.5uF ? or 1.5mF

How do you calculate the capacitor ?


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Hey this solution would help me in some installations, do you have more info (or copy and paste the text so we can translate.) thanks!


Use LED or GAS lamps only. Only low power consumtion devices. 

First column - "Type of bulb"

P1 - power of BULB in WATTS.

C1 - quenching capacitor - 1,5 micro Farades to 3,3. 

C2 - 0.47 micro Farades. (that solution is need if your LED lamp is cheap, there are a lot of expensive bulbs witch have that solution included). Only cheap bulbs blink.

Good luck.

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Hi, can you share the formula that you use to calculate the capacitors? For example, what should be the capacitor 1 and 2 in case the load is LED lighting with transformers, about 40W total?

Thanks a lot!

I don't have formula. Experimentally - U'll need 7-10 micro Farades capacitor for that solution.

I guess that means -- two 4,7 micro Farades capacitors. Parallel connection.

Hi, has anyone else tried this? This will be great if it works, my question is how will this work when I have 4 lights in the circuit, these are 12W LED dimmable lights (dimmable by turning them on and off and the lights have 4 brightness settings).

Will I need to change the capacitor sizes?

Hi, i don't think that this solution wil work with dimmable lights. It is not good idea. This solution is only for LED or GAS lamps only.

Am I right that provided solution is based on the fact that the value of current through the switch is very low?That's why the lamp (if it's cheap) can just blink in the off position of switch.  

One more question - is that required that you have to break the "Line" instead of "Neutral"? Because usually switches break the "Neutral".

It's possible to install a sonoff wall switch without an existing fact you will need a wall switch and sonof basic and create a scenario to be able to use them both at same time. All switch light are using a hot wire coming from the light enclosure and another wire to send hot line to the light. The neutral stays at the light enclosure. Basically what you need to do is to use the 2 wires between the light and the switch to power the switch, so you will connected them to the neutral and hot wire (black and white wires). From that same enclosure you will install a basic sonoff switch between the light and the power line. Then on you app yu will create a scenario to trigger the sonoff basic from the wall switch the same way as a 3 way switch settings. That's it!


Rouchdi, your solution does not make sense as the light bulb point does not even have live wire. The solution has to be existing wiring. To use sonoff basic with rf, basically it is better to by pass the wall switch (just always on) and replace the wall switch with battery operated rf transmitter.

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Justin, please check my diagram and what I write about the change in the wiring, live and neutral wires runs in parallel to the Wifi Wall switch (1) and to the sonoff Basic(2)'s my current installation and it's working. You need to add a scenario (in fact 4 small scenarios ON1 -ON2 ; OFF1-OFF2 ; ON2-ON1 ; OFF2 - OFF1 ) to the app in order to make the wall switch trigger the sonoff basic and vice versa!

Your diagram need additional live wire to the bulb which most of us do not have

Black wire in live and white is neutral, in both diagram the bulb has both live and neutral wire...I don't get your point. This is a typical installation for North America and Europe.

What he is saying is do some rerouting in the light bulb junction box.  In old construction typically the feed wire from the breaker/fuse panel containing the L and N came to the light bulb junction box in the ceiling.  The circuit was broken by running two wires to the switch.

1. Disconnect the switch and replace with wifi switch using existing two wires as L and N.

2. In the ceiling junction box tie the 2 wires going to the switch to L and N.

3. Connect a Sonoff Basic between L and N in the ceiling box to the light bulb.

Now you have the wall switch fully powered by L and N.  Use a scene that turns on the Basic when the wall switch is turned on and off when the wall switch is turned off.

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