Since this is a fictitious example, we shall control the following devices either by raspberry pi or PLC (we hope it will be completed someday!)

Lock:

This is a digital lock of the main door of our fictitious house. We can tell the system to open the door, lock the door remotely. We can check the system if the door is open or closed. We can generate alarms also. For example, if the main door of the home is opened for more than 30 minutes, we can generate an alarm that can be visible in the SCADA software. We can create a method in the OPC-UA server or create variables that can be set true or false from the SCADA.

Thermometer:

We can read the room temperature and set the room temperature. We can get an alarm if the room temperature of the home is above 50-degree Celsius. This data will be read from an analog channel of the Raspberry pi or from the PLC analog input card.

Valve:

Our home floor has circulating water. Warm or cold water will be circulated around the floor depending on temperature. Warm or cold water will be activated by a solenoid valve. OPC-UA server will do the work for us.

AC motor:

Our hose has a main gate that can be opened or closed remotely. When the door needs to open or closed then we run the motor. Open and close position is sensed by 2 proximity sensors. We have also thru beam (light sensor) that will indicate if there is any obstacle while it is closing. We shall use Magnetic contractors to generate a signal to start the AC motors. Though we shall not use VFD we shall discuss VFD in detail.