The relay module is a separate hardware device used for remote device switching. With it you can remotely control devices over a network or the Internet. For the industrial use of the relay modules, it is important that they can easily be inserted and quickly be mounted. Devices can be remotely powered on or off with commands delivered over a local or wide area network. You can control computers, peripherals or other powered devices from across the office or across the world.
The Relay module can be used to sense external On/Off conditions and to control a variety of external devices. The PC interface connection is made through the serial port.