The ABCs of SCADA Systems

The meaning of SCADA systems can be explained quite easily. SCADA stands for supervisory control and data acquisition. In simple terms it refers to a computer system for analyzing and gathering data in real time. SCADA systems are employed for monitoring and controlling equipment or a plant in various industries like transportation, gas refining, oil and energy. It is also used for waste and water control.

scada system

Purpose and Goal

These systems are designed to collect information like where a pipeline leak is taking place (or some other problem). Once this has been detected, the info is sent to the main control center, notifying the people in charge that a problem has occurred. This allows the right people to conduct control analysis. In the case of a leak they will check if the leak is crucial. Information will then be displayed in a manner that makes it easy to determine what action to take.

Some of these systems are simple but others can be complex. Simple systems are the ones used in office buildings and those that check environmental settings. The more complex systems are those that check the workings of a water system or those of a nuclear power plant.

While these systems have different features, they are all designed for the purpose for setting off alarms in case there is a problem. Most of these units have override controls but they are rarely used anymore. That being said, control set points can be modified and are regularly done so.

Context and Components

The term “plant system” when spoken in a municipal context denotes waste water and water treatment facilities. When speaking of a “regional” system, it includes control valve stations, chlorination stations, pumping stations and many more.

Three parts make up a typical SCADA system. They are the Human Machine Interface (HMI), Remote Telemetry Units (RTUs) and communications. Every RTU gathers data at a given location. Communications on the other hand, transmits the data from that location to an RTU site or a plant. The HMI will show the info graphically so it is easy to understand.

Once the data has been received it will be archived and if needed, alarms will be sent out. Plant communications will take place using different methods like fiber-optic, wire or data cable. The most commonly used for communications for regional systems is radio. An HMI system is basically a very powerful computer with alarm and graphics applications.


The reason why SCADA is so popular is that it helps you cut down on labor costs. Simultaneously it also enhances the performance of your plant and is very reliable. By using this system to collect data, you cut down on the need to have a person on the site to collect information. This also reduces the chance of errors and you can perform the checks as often as necessary. By using a SCADA system you will find out the nature of the trouble.

Now that you know the meaning of SCADA systems it becomes easy to see why it has become a standard feature in plants. One of its features that is not well known is the speed at which it can transmit data. With this system you can be assured of getting information as soon as any problem comes up. Given this fact, it’s likely that their usage will only increase.

Loy is a free lancer writer of and



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