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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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thanks mate!

will try it later on


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ok, hooked up my switch but it wont stay on . 

gotta add that I've tried with 3.3 and 6.6uF ...any idea, @sshRage ?

my connection diagram attached.


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thanks mate!

You are welcome.

Try 4,7 micro Farades.

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thanks mate!

that clarifies it :)

one thing, what C1 value would be sufficient for approx 30W LED (3 x 10W LED bulbs)



If you have Live and Ground wires it means just the same as it is NEUTRAL and LIVE.

In my schemes im talking about 3 wires. LIVE, NEUTRAL and GROUNDING. And i'm telling not to use GROUNDING wire to connect that stuff. Cause grounding is for emergency only.

If you have 2 wire system, where there is LIVE and GROUND, you should consider GROUND and NEUTRAL the same.

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Hi sshRage,

whole idea looks interesting but need some clarification:

on yours diagrams you've mentioned 2 wires: Neutral and Live while most of us got Ground and Live wires only so would you be able to do another diagram with L/G wires by any chance? 

Thanks in advance

Actually this is a "classic" solution for the RF switches that don't need a NULL line (like Livolo). They maintain a residual charge for the electronics.

That is why those switches come with a capacitor in the box, to be put in parallel with the LED bulb to prevent flickering.

 If you have like 4 or more LED bulbs the capacitor is needless because they don't flicker anymore.

Just like this scheme. And since those work reliable with no issues, I believe this solution for Sonoff switch is OK.

You dont need C2 because you ve got many LED spots, and I think that current in OFF postion of the switch will be too small to make LEDs blink.

Yep, aproximately 1uF for 5Watts. But i did not tested this solution for 60Hz. Onle 50Hz. Try it by yourself.

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Yes there is one zone with 10 LED spots, in parallel turned on/off by one switch.

So the C2 is actually the  "anti flicker" capacitor that counter the residual current from the C1?

I deduced (from yhe schematic and your answer) that the calculation is about 1uF/5W of bulb power for the C1 :) ?


I guess you are going to make them turn on/off simultaniosely. There will be one zone of ligh, not 10 zones.

And you will connect all LEDs in parallel connection. And you will use 1-gang wall switch to turn all of them on/off.
Then you will have to summarize power of your LEDs = 50W. You will need to use apox... 10 Micro Farades capacitor to make them work. And I thin that you will not need C2 capacitor. 

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Very interesting Idea. 

The thing is I have 10 led spots of 5W each in the living-room, will the capacitor value still apply (or which one)?

Here is a solution scheme for multi-gang switches. 


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To Michael Ingraham and  SonOffJunky - your theory looks fine. I think it'll do. But please try it in practice. And add your results in this post.

To E W.

That scheme is for GAS or LED bulbs only. EW -  you are right. LED and CFL bulbs have a wider input voltage range. That's why they are working fine, and you will not sence the difference. Do not use that scheme for classic bulbs. Classic bulbs will burn darker.

And your guts have good "premonition". This is not a best solution. Best solution is to "run a neutral wire and do it right". BUT! If it is not possible - it is better to do that scheme, but not the one with the grounding wire. 

About heat - there are not heat at all on METAL-FILM capacitors. Try it by yourself. Use that type of condensors: (I don not know the right translation for this type). Please name it.


There are twomore things you should know about that scheme: 

1)If your bulb is dead - whole current will flow in C2. Like a shortcut. In that case your WiFi switch will power down in ON position. Then it power up again - and again OFF. In containious loop. 

2)If you will change the WiFi wall switch to the classic one, leave the C2 capacitor on the celling and you bulb will die - that will a problem. Whole current will flow to the C2. I guess it will burn.

So - dont leave a C2 capacitor on the celling in case you decided to change wall switch from WiFi type to the classic one.

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