Basic components of PLC and SCADA?

Basic components of PLC and SCADA ?


1.It is a solid state device. It controls the output of the process through the program given in Ladder diagrams.2.I/p & O/p are represented in NO,NC and coil contacts. 3.Each component involved are defined using Address.


1.It is a software. Used to monitor,control and acquire data from field devices even from remote locations.2. I/p & O/p are represnted in images.3. Each object is defined using name. Since every industry is getting automated,it is important to know PLC and SCADA and its functions.

PLC: P rogrammable L ogic C ontroller , it is a Industrial Computer ( It is a hardware) that performs discrete or sequential logic in a company environment.

It was originally developed to replace mechanical relays, timers, counters.

PLC are used successfully to execute complicated control operations in a plant.

It is a controlling device that controls output process through logic programs given to it.

Examples of some important brand PLCs are; Allen Bradely, Siemens, Omron etc

Applications of PLC:

  1. Reliability in operation
  2. Flexibility in control
  3. Online/Offline modifications
  4. Speed in operation
  5. Security

SCADA: Supervisory Control and Data Acquisition :

It is a monitoring and controlling software, runs on PC and is generally connected to varies PLCs and other peripheral devices.

Examples of SCADA Software used in industries are; R.S View, Wonderware, Win CC.