DIY : Automating My Apartment Door Buzzer – Anthony David Adams – Medium

Setting Up the Shelly 1

The Shelly 1 Relay
  1. Take the cover off the wall mounted intercom / buzzer.
  2. Determine what contact points needed to be closed to trigger the lock (for me this involved looking at the push button and visually following the trace on the PCB, then testing it by using a wire to jump the switch and listening through the apartment for the Buzz.) I also used my multimeter to determine the voltage (in my case it was ~ 12v).
  3. Attach wires to the contact points in the intercom and run them into the 
    I / O pins on the Shelly 1.
  4. Attach the power source to the Shelly 1 via the L/N pins.
  5. Follow the set-up instructions for the Shelly and get it connected to your local wifi network.
  6. Set up the Shelly 1 as a switch with an automatic 3 second turn off (If you don’t do this, the door will keep buzzing to let people in until you press the button to turn it off again.)
  7. Put the intercom back together and clean up your wires.

Congrats! At this point you should be able to control your door buzzer using the Shelly app on your phone or through the cloud interface!

There is a incredibly helpful official facebook support group for the Shelly that can help you if you get stuck.

You could stop here if you want, but if you’d like to learn how to access your Shelly via the internet directly or to set up a phone number you can text to open your front door, read further!

Controlling the Shelly via the Internet.

  1. Secure the Shelly 1 interface page via ‘settings’ in the the app and set a username and password (this prevents anyone from controlling your Shelly from the internet)
  2. Set up port forwarding on your home router
  3. Set up for your router so that you can have a static web address — there is a free and paid version.
  4. Now you can access the control page for the Shelly from any internet connection and you can also utilize the API functionality.

Now, anytime someone visits the following link, the lock will automatically open for 3 seconds.

You could simply share this link with your guests or you could call this as a webhook from an app and open the door on command.

Controlling the Shelly via SMS

Now that your Shelly is accessible via a webhook, there are many ways you could implement a solution that allows you to open your door via SMS.

What follows is a simple way I found to do it using Twilio and

This is by no means the best /only / cheapest solution, but it works for me.

If you find a different way you prefer, please let me know in the comments section.

Setting up Twilio +

  1. Create a Twilio account and buy a phone number. (There is a free demo available!)
  2. Create a account and connect your Twilio Account as a channel
  3. Create a Flow that calls a webhook to your Shelly.
  4. Customize your Flow to your heart’s content!

My flow is pretty complex and allows me to invite others via text and automatically grant their phone number access, request wifi password reminders, and has limited password protection so not just anyone can text “door” to my number and open the door.

My custom Flow

A Note on Security

Exposing your Shelly to the internet via port forwarding increases your risk as you are providing a way through your home firewall.

Additionally, providing an SMS access point to your Shelly is also creating a situation in which people could guess your phone number and get access to your front door if you don’t build in additional password protection.

Further, if someone were to send lots of texts to my current system, they could run my bill up considerably!

Please consult with experts and proceed at your own risk!


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