[Q] How does Smart Dimmer Switches work?

I will tell you the entire answer to the question in title in this first paragraph itself. When you first install this switch in your home using a smartphone with their app, the switch will get paired to your smartphone using Bluetooth. Then when you register a new account, this switch will be registered with their cloud service which will then be later used to be accessed via smart device voice assistants such as Amazon’s Alexa and Google’s Assistant.

Why do I need to pair for first time setup?

Manufacturers like Martin Jerry have created their own app which will be used by people to conveniently manage the company smart device such as this dimmer switch using a smartphone.

This mobile app will allow you to register a new smart device and gives you a way to manage them. You can do voice command to dim a light. Or you can use the app to control the lights.

On top of it, you can also set up timer and can be scheduled to power ON and OFF.

This mechanism requires the switch to be able to communicate to the cloud service. For that, we need to enter home WiFi password. When you about to pair the dimmer for the first time, you need to be connected to the home WiFi first.

Now the app knows the current WiFi SSID or name. This will be shared to the device along with the password you enter in the screen prompt by the app itself.

This credential will be used by the device to connect to the internet cloud service. The app which helps you to register to a new account will registers the device with the help of the device’s unique ID. This ID is shared by the dimmer to the app on pairing.

Hence to setup the dimmer, you need to pair it up using Bluetooth.

Do I need my smartphone every time?

You don’t necessarily need your phone to be connected to the WiFi for you to control this dimmer switch. You can use other ways to control it. You can use Amazon Alexa to control the dimmer. Or you can use Google Assistant to control it.

You need to set it up for the first time with Alexa/Assistant voice service. Then they will control the bulbs via simple commands like “Hey Google! Dim the lights to 60%.”

Hence you don’t always need a smartphone!

What does the cloud service do?

In the far away land, there are hundreds of servers running continuously to manage the device status. When you make a command, the assistant (Alexa or whatever, may be the app itself) will send request information to the service on which you have registered using the app.

Then your device status will be marked accordingly on those server end.

Here in your home, using your home WiFi, this dimmer will continuously checks for the device status, talking to the cloud service.

When there’s a change in the status at the cloud service end, this dimmer reads it, and controls the load (bulb) accordingly.

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