Somfy Motorized Shade and Relay Shield

Hi All,

I’m pretty new to home automation. I’ve installed a Nest and an OpenSprinkler in my home, pretty basic stuff. I’m now working on a prototype for an automated shade.

I’m trying to use a Spark Core and Relay shield to operate a Somfy L50 . I’ve successfully been able to turn on and off a lamp using my phone and the core/relay shield.

Please see the images below.

The green wire is the ground (no problem, i get that). The white is the common.

When I send power to the white and black wire (from an outlet plug) the shade rolls up. Then when I switch up the wires and send power to the white and red wire, the shade rolls down.

My question is, how can I wire this to the relay board? I’m thinking one relay to go up (black wire) and one relay to go down (red wire). But i’m not sure how to handle the power/common wire.

Does anyone have suggestions on how i would need to wire this?

Thank you.

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Relay Shield


  1. White wire goes to -ve of power supply…

  2. Red goes to NO of Relay 1 (R1)

  3. Black goes go to the NO of Relay 2 (R2)

  4. +ve of power supply goes to Common of R1 and using a wire (thick enough) you can find to connect from the Common (R1) to Common (R2)

Just make sure your code doesn’t switch on both at the same time and the Relay rating is sufficient for the shade motor :smiley:

Looking fun!

ok my bad! I got a little mixed up. Give me a few minutes to rewrite the above :smiley: DONE

Hi @AtlanticSurfer

The green and white wires don’t need to go through relays–they are just connected to same color wire on your AC wall plug, white to white and green to green.

The black wire from the wall plug goes to the common terminal on TWO relays and the black and red wires from the motor go to the the NO terminals of these two relays. Obviously don’t turn them both on at the same time or the motor will burn up.

Have fun!

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kennethlimcp, bko is correct. This is an 120VAC powered unit and only the “hot” side needs to be controlled. :smile:

Guys, thank you for the responses!

I spent part of the day, in the man cave. It isn’t pretty, but i’m wired up. I was able to run the motor up and down with the Spark App. I’ll start coding against my prototype on Monday.


AtlanticSurfer, just an observation but you may want to use a plastic wall box instead of a metal one :wink:

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Peekay, good call, thank you. I will switch that up.

Hi @AtlanticSurfer

I think this is a very interesting project–thanks for posting the pictures!

Wow, is that a big motor. I have been thinking of doing something like this for one of our bigger shades but it would be a bit retrofit.

Were you able to buy the motor without the Somfy IR/RF module or are you just not using that part?

@peekay123 is right about using a plastic box in two ways–the relay board is not insulated and the core needs WiFi RF signals.

Your prototype wiring looks great but for the in-the-wall service you should use something like NM-B 14/3 wire which is 14 ga wire with 3 conductors and ground. This will usually have black, red, white and bare wires.

Keep us posted–this is a great project!