Generally when the PLC is integrated into process control or automated control systems all the components work together to form a complete control system. <div>
The system is normally made up from a combination of PLCs, networks, I/O, software and terminals. Many sub systems are used with many terms describing them
It consists of a mixture of engineering and statistic disciplines that deal with the architectures, mechanism, and algorithms for controlling a process.
It consists of a system, technique, or method for operating or controlling a process automatically, by electronic devices and making human interaction a minimum.
A transmitter (instrumentation) is reading a temperature of 150 degrees Celsius. The PLC communicates with the transmitter by the transmitter sending an input to the PLC. The PLC is set to turn on an air conditioner to cool the temp back down to 145 degree Celsius.
The output is signaled from the PLC and the air conditioner turns on. The temperature cools from 150 to 145, and then the transmitter sends another input to the PLC to tell it the correct temperature is reached. The PLC then turns off the air conditioner.