PLC and SCADA are both used to monitor and control equipment in process automation across many different industries, such as telecommunications, water and waste control, energy, oil and gas, and transportation.
Because of the technological complexities of these modern day systems understanding how each plays its part can be rather confusing.
PLC AND SCADA SIMPLIFIED
In simple terms—SCADA controls the entire system of which the PLC is a part of.
A Programmable Logic Controller also known as PLC, is a piece of hardware used to read sensors.
PLCs receive information from connected sensors or input devices, process the data, and triggers outputs based on pre-programmed parameters
They were initially developed in the automobile manufacturing industry to provide heavy duty, programmable controllers to replace hard-wired relays, timers and sequencers.
They are now used as automation controllers suitable for harsh environments in many different industry processes.
PLCs are also used to function as real-time systems, since output results must be produced in response to input conditions within a limited time, for continuous proper operations.
SCADA IN DEPTH
Supervisory Control and Data Acquisition (SCADA) is monitoring software used to control the PLC and record data, even from remote locations.
SCADA systems use computers, networked data communications and graphical user interfaces for high-level process supervisory management by relying on PLC’s and discrete PID controllers to interface with the process plant or machinery.
SCADA systems are managed by an operator using an operator interface which allows the individual to monitor and the issue process commands through the SCADA computer system.