Communication HMI PLC Basics PLC Learning Sensors

The 7 Essential Parts of a PLC System

We will now look at the parts of a PLC system. When I was in school PLCs were just in their infancy. We were taught that the PLC consisted of the central processing unit (CPU), analog and digital inputs, and outputs. Everything was programmed with dedicated handheld devices and/or software devices on specialized hardware. We now have modern PLC systems that are capable of so much more. Let’s look at how we can now break up these modern PLC systems into the seven essential components.

Inputs and Outputs (I/O)
Analog I/O
Specialty I/O
Programming Tools