Another example for automation is picked and place robots that pick and placed things again and again. So PLC’s also used in Automation to do same things billions or trillions of time a day which is impossible for a human being or if it’s possible so humans actually can’t do same work again and again but the robots can they will not get tired. Which of them car you are going to automate obviously the second car which needs daily working the same things. Among of both cars, 1 is used only one time to travel between “A” to “B” area and second car travel daily from “A” to “B” area. Where is the need of Automation? If you have 2 cars and have a chance to automate 1 car. So it’s the controller that works under the certain logic and that logic can be changed or can be altered by using a programming. PLC is basically a controller that you can program. To manage all that the logics will be used so called a Programmable logic controller. For example we have a controller for elevator If you are on the 3rd floor and calls a lift after getting in and pressing the button of ground floor and at the same time in 4th floor someone press the call button what exactly elevator perform first on that time.? does it go up and pick them first or does it come down to the ground floor first.

In previous we see controller controls different parameters but the parameters with a certain logic. Now why it is called as a logical controller. So controller controls different parameters which are ultimately affecting the system performance. If the speed is increased and we want to stop the vehicle what will we do, we remove the feet from the accelerator or press the breaks ultimately we add or remove something in the system. For example, if weĪre controlling the vehicle either we control it by steering or by breaks or something else. What is the meaning of controller.? What is the importance of controller? When we say that the system is controlled the exact meaning of this is that we controlled the different parameters of a system.

Plc ladder diagram examples