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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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I've done some checking and they are for sure in series. And when I've disconnected 3 out of 5 the remaining 2 were working properly. with 3 they start to flicker a bit. As there is no option for me to put a bigger cap in there would connect them in parallel help?

If they are in series removing one bulb would cause all to go dark.  I seriously doubt the lights are connected in this manner.  If removing one doesn't extinguish all others then they are in parallel.

The reason 2 lights work normally when the other three bulbs are removed is because you have reduced the load by 3/5ths and the voltage drop is much less.  The capacitor you currently have in place is apparently passing just enough current to supply two bulbs.

If you have capacitors available start placing the caps in parallel until all 5 lights are burning normally.  You can do this as a test outside the box.  When you have it working this way then add up all the capacitor values and order yourself a single capacitor of that size. 

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This is intended to overcome any possible language issue.


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Hi, You are right I don't know why I thought it's in series. I will try wit a lot more caps as 4,4uF seem not enough.

Thanks for all the hints :)


I've actually had to give up for now :( I've checked lights again with classic switch and they work perfectly fine as they were before. But with S-mini they are dim and are flickering a bit and one of them goes out. I've put all the caps that I had, in total there were 17,6uF there and the effect was exactly the same as if there was 4,4uF there :( I don't know what's happening. Maybe s-minis don't like this kind of setup?

Hi Kamil, sorry for asking but just to be sure: did you connect the capacitors in parallel? That is All leads of one end tied together as one and all leads of the other end tied together as one.
If the enormous increase in capacity doesn’t have any effect, you must have connected something not quite right. Can you post some photos of the connections you made so we can check?
If you think that’s it’s the mini, you could do a test with standard SonOff. You could very well be right that the Mini doesn’t work with the capacitors. Would be interesting for us all to know as well.


Yes, Caps were parallel for sure. And connections were as on the pics before. So probably everything was fine. I've also tried reversing the blue with red on the pic going from the ceiling but all the time it was exactly the same :< I don't have a spare sonoff to test so I will not be able to check.

Stealing a clip of the original drawing...  Here is how and where the test caps are connected.


Hi Malik, I think you have switch the blue wire and the wire from the capacitor. But I cannot be shure because you have posted a schematic by not an actual picture of the switch and the connections.

" very well be right that the Mini doesn’t work with the capacitors"

Aside from a possible bad relay inside, the "mini" vs any other switch doesn't have any effect.  It is just a pair of contacts that completes the circuit.  In fact you can leave it out of the circuit for a test and just tie the hot wire to the capacitor and the wire leading to the lights to the other side of the capacitor.  That is essentially what happens when the relay closes inside the sonoff device.  If you have enough capacity the lights will burn properly, if not they will not.

C1 has to pass enough current to power the lights without dropping the voltage to the point where they start to dim.  It is as simple as that...

Here is a solution scheme for multi-gang switches. 


Sorry Maybe it's a foolish question but this yellow wire also running into the switch is it a crutual component of a scheme? Or it only dublicates  red one. Thank you.  

Here is a solution scheme for multi-gang switches. 


If I gonna use sheme with 2 gang switch  should the value for C1 capacitor be calculated for 2  bulbs (P1(wt) +P2(wt)) or just for P1? Also should I put additional capacitor in order to prevent P2 flickering? Thanks


Sorry to revive an old thread, but it seems there are knowledgeable people here that can answer my question.

I bought a few no-neutral light switches from AliExpress. Each comes with a 2uF capacitor corresponding to the C2 capacitor in the diagrams of sshRage. Overall they work great, the lights don't flicker when the switch is on. But I have two issues:

1) Some LED lights (GU10 downlights) flicker when the switch is in the off position, presumably due to some current passing through them. (I don't know if the capacitor is supposed to do anything when the switch is off.) The AliExpress description says the switch requires the light to be minimum 5W. The problematic LED bulbs are less than 5W but there are 8 of them connected in parallel, with a capacitor at the first one. Also tried putting a capacitor on the second one, no difference. Also tried putting more capacitors on the same bulb, again no difference.

2) The switch doesn't power up when there's only a capacitor and no bulb. This is not a big issue per se, but it would be nice if the operation of the switch doesn't depend on the presence of a bulb.

Could both issues be solved with a smaller capacitor? Or perhaps with more sophisticated capacitor Apparently the no-neutral SONOFF T4EU1C switch comes with such a sophisticated capacitor. DrZzs showed on YouTube that this switch works without a bulb, presumably due to the resistor inside it? SuperHouseTV inspected that capacitor device in this YouTube video as well. Below I've included pictures of that device made by a friend, where you can see two capacitors, a resistor, and a thermistor.

Sadly I can't obtain such a capacitor easily, unless I buy some switch from AliExpress that will take weeks to arrive. But if you guys think it could help, maybe it's worth buying one for the test?





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