What is SCADA?
Supervisory Control And Data Acquisition or SCADA is a system used to monitor and control a plant form a central location. This is not frequently used because of the control override possibility. SCADA itself changes the control set points quite frequently. It is widely used in water treatment plants and lately it has been used chlorination and pumping stations.
SCADA system is composed of 3 main elements.
- RTU (Remote Telemetry Unit)
- HMI (Human Machine Interface)
The function of an RTU is to collect the onsite information and this information is sent to a central location with the help of the communication element. If system wants to send information back to the RTU then this communication element take it back too.
The function of the HMI element is to display the information received in an easy to understand graphical way and also archive all the data received. It is usually a high end computer system capable of displaying high quality graphics and running advanced and complex software.
Communication happens through various means. It will happen via data cable within a plant or through a fiber optic. The communication may happen via radio between different regions.
Why is SCADA Popular?
The major reason of its popularity in the manufacturing industry is that it significantly reduces the labor costs and improves the performance of the plant. Management can save time as well because the information is gathered by SCADA at a central location so the personnel do not have to go and wander about on site.
Another feature of this system which is seldom appreciated is its capability of displaying the trends. When information gathered is displayed graphically, the system shows the developing problems and helps the management in taking the corrective measures. The SCADA system may be difficult to configure at first but it is extremely user friendly and easy to use. ?