A relay is a component that's able to open or close a circuit depending on the presence or absence of voltage at the input. In practice, it is a switch operated by an electromagnet. Let's understand this basic concept, learn how to open and close a circuit and make it programmable, and understand well how this is the starting point to open up more complex and interesting scenarios such as the remote control of devices, home automation, and more.
In this recipe, we will see how to open and close a circuit using a Relay Module and how to make its use programmable through a Delphi application.
