SCADA is an acronym for supervisory and data acquisition, a computer system for gathering and analyzing real time data. SCADA systems typically used to control geographically dispersed assets that are often scattered over thousands of square kilometers. In the past, communications between field controllers and host computers were dependent upon serial communications, most typically RS232. Data rates rarely exceeded 9,600 bits per second and resulted in ICS needing to be co-located or include multiple relays.
As digital technology and data transfer rates improved, networks extended to include more remote locations, and asset owners started to migrate their serial SCADA circuits and converted to digital networks. While this migration offers asset owners significant benefits, there are pitfalls. An improperly designed network can be a conduit for cyberattacks.
Because a tremendous amount of data is collected, the success of the SCADA system is dependent on the master controller successfully communicating with field controllers, such as RTU, IED, and PLC. If communications fail, the field controllers must individually control the remote facilities until the system re-establishes communications and the RTU or PLC can report to the master station.
Using SCADA components provides flexibility, in that they can integrate the HMI from one vendor with the PLC or RTU from another vendor, provided they use the same protocol. This means you can replace the HMI software without having to replace the RTU or PLC (and vice-versa). Click the button below to for example of SCADA uses.