Plc Block Diagram. Used primarily for logic boolean operations and is easily understood by electricians and control technicians. Simple fbd block looks like as shown in picture.
Plc function block diagram allows to put functions written with many lines of code into graphical boxes so you can easily connect them to make a bigger plc program. Thereby we can easily connect them to make a bigger plc program. A simplified block diagram of a plc shown in above fig.
Cpu central processing units.
The central processing unit is the heart of the plc system. The input section converts the field signals supplied by input devices sensors to logic level signals that the plc s cpu can read. Which become in conduction region give a triggering pulse to at the gate of triac. Input and output i o modules.
