Controlling a Relay CloudX
A relay is an electrical controlled switch, they are switches that open and close circuits electronically or mechanically. They are most times referred to as electromagnetic switch operated by a small electric current that can turn on or off a much larger electric current. One beautiful thing about a relay is that it helps to isolate a circuit. For example, controlling an electrical AC appliance from a DC circuit. Every microcontroller doesn’t have enough power to switch a relay, so you will have to use a transistor to switch it, you can find samples of how to switch a relay using transistors on the internet because I will be using a relay module which already has a transistor on the board.
The relay module has made every design easy for makers; there are available modules that have up to 16 relays on the board. It makes our projects faster to make as most of this relay modules operates with just 5v.
The relay module has the VCC (5V), GND, IN(control pin) while at the other connector part, it has Normally Close(NC), Normally Open(NO) and the Common (COM). You can learn more about relay if you don’t understand those terms.
The module is powered through 5v and GND pins, when IN pin is HIGH, the relay clicks and COM pin is internally connected to NC, when IN pin is LOW, the COM pin is back to NO.