Hello everyone,
I’m starting to automate my home, so I bought 2 sonoff T2 3 gang to wire my roller shutter.
Do you know where I can put this wire to the sonoff Switch? I will flash tasmota on it before I wire it.
I’m software engineer, and very dumb about electricity and electronics. 
Thanks for your help
If you don‘t have a neutral wire in your switch box, your Sonoff wil not work.
Hi @Tukks,
Your “I think” statement has me a bit worried. You ought to invest in a multimeter and positively what you are working with. Guessing when dealing with mains power is not a good idea.
Regards,
Burzin
Even if you have a neutral (well, looks like…) I would suggest to use a 2 gang instead of a 3 gang.
A 2 gang switch has 4 “buttons”, a 3 gang switch has 6 “buttons”.
When flashing with current Tasmota (https://tasmota.github.io/docs/#/) you can easily switch on shutter support, including interlock and direct positioning.
Interlock is very important to prevent motor damage. In a usual installation, the scheme is like this:
http://www.next.gr/uploads/36/Rolling_Shutter_Control_Circuit_Diagram-1366561615.png
A usual shutter wall switch is built in such a way, that it’s impossible to switch both directions ON at the same time.
Tasmota interlocks pairs of relays to ensure, that only one relay is switched on at the same time, so you can change direction by hitting the opposite ON “button” or stop the shutter by hitting the corresponding OFF “button”.
Burzin_Sumariwalla
I will use a voltmeter to test if the blue one is a neutral wire, but in Fance, by convention, a Blue Wire is a neutral one, and the Yellow/green is the ground.
Checking the Tasmota doc, If I activate the interlock option, all the three “buttons” will be in interlock state.
So I will use this 3 gang, I will have the third button doing nothing (I know, I made the wrong order on Aliexpress, and I don’t know where I can use this switch at home if I don’t use it for my roller shutter)
A big thanks for your reponse Udo_Hartmann with the scheme. Now I understand the interlock state.
I will double check everything, and I have family member electrician (I fix computer, they can fix my wire 
)
Have you got any door position sensing? How will openHAB know when to stop “pressing the button”?
When you are stood there, you know not to press buttons when there is something/somebody in the way of the door. Have you considered how safe this will be if the door starts moving unexpectedly and/or unattended?
So I wired my 3 gang.
I just used 2 gang instead of three, one gang is useless.
I activated interlock, everythng work fine.
Now I need to calibrate everything.
@rossko57 The shutter know his position with a timer.
If the shutter start mooving, no problem, there’s nothing on his way.
Thank’s for you help everyone
