How to turn a regular switch into a WiFi switch

Shelly WiFi Relay - WiFi Switch

If you are interested in going home automation of your house little by little, one of the first moves that you should take into account is to convert the switches into wireless models, and contrary to what you might think, you don't need a smart bulb to turn on the light with Alexa. You will be able to continue using your current installation, just with a new addition.

A WiFi relay

Shelly WiFi Relay - WiFi Switch

The only thing you need is to place a wifi relay on the inside of your switch, just behind the mechanism that goes on the wall. Installation is quite simple, and you will currently be able to find a good number of different models on the market. One of the best options is the shelly wireless relay, a quality brand that offers a very compact model that will fit perfectly into the switch hole.

This wireless relay is responsible for turning on the light when you send the order through the official application or using a voice assistant, but it is also capable of controlling the bulb by responding to the actions performed on the wall switch itself. It costs less than 15 euros, and is the most practical option when it comes to wirelessly control a light bulb.

The advantage it has is that you don't need to buy smart bulbs, jumpers or any other accessories to convert the light to smart, being able to continue using the current switch you have on the wall. You will need one device per light (if you want to control it individually), or one per group of lights.

WiFi relay types

Shelly WiFi Relay - WiFi Switch

Brands like Shelly offer a wide variety of different models, and although they all seek to provide the same function of controlling a light or a switch wirelessly, there are variations that will allow you to know the energy consumption of said point to know what energy is being consumed from a specific point of light. Remember that these relays are not only used to control lights, but they could also activate and deactivate sockets, which would allow you to know how much an appliance would be consuming.

How to install

Shelly WiFi Relay - WiFi Switch

To install the relay, the first thing you will need to do is access the inside of the wall switch. Try to disconnect the electrical current by lowering the corresponding circuit breaker on the light panel, and once the situation is assured, proceed to remove the switch.

All manufacturers include instructions to indicate which cables you should connect to the device, but basically we will have one cable that goes from the original switch to the relay (so that it can send the order to turn the light on/off), two cables

Taking into account the connections and the fact that we need to have a neutral cable, the installation will most likely have to be done in the registration box closest to the switch, since that will be where you will have all the connections.

In Shelly's model, the connection would be as follows:

  • O: Cable that comes from the bulb (previously on the switch)
  • I: Direct connection to the phase cable (black/brown) of the registration panel
  • SW: Cable that went from the switch to the light bulb (the same as point O)
  • L: Direct connection to the phase cable (black/brown) of the registration panel
  • N: Direct connection to neutral wire (blue) of the registration box