Process control system block diagram

About this process control system block diagram

A process control system block diagram is among the most important representations that demonstrate the control and feedback mechanisms needed for achieving a temperature set point in a given space or device.

The figure's center highlights a thermostat's role as a control device. It performs an ON/OFF function based on the comparator's signal. The comparator compares the real temperature of the room with the set temperature and, therefore, determines the action of the thermostat in the loop.

Continuing to dissect the diagram, the controlled temperature is indicated as a command to the heating system. This is also an action device in the system; which changes the temperature of the room according to the control signal given to it, thus striving to achieve the specified set point.

As a feedback signal derived from the temperature sensor, it plays a vital role in ensuring accuracy in this process. This feedback mechanism reports the room's current temperature. The comparator then uses this to create a closed control loop.

This block diagram represents a very simplified view of a block diagram of a process control system. It perfectly captures the parts that work in synergy to enable automatic control of temperatures.