A person’s desire to shift heavy monotonous labor onto the shoulders of machines and mechanisms is directly related to such, at first glance, the unfortunate property of psychology as laziness. However, any device should be controlled, which, of course, is easier than working on your own, but it is also not easy.
This is how science arose, the name of which comes from two Greek words meaning “self” and “acting”. So, automation is a system of knowledge that allows you to make machines work without human intervention. This discipline is studied in technical universities and is reputed among students no less difficult than the notorious "termeh". And no wonder, mastering the theory of automatic control (TAU) is impossible without a very good level of training in higher mathematics and physics.
Automation of production is partial, complex or complete, differing in the degree to which a person is detached from the process control process. The main reason for its wide distribution is economic feasibility, since the maintenance of technical equipment is cheaper than personnel. However, as practice has shown, the quality of the finished product is also higher in cases where the human factor is minimized.
If we consider this theory in a simplified form, then it will not seem so complicated, the main thing is to learn its basic concepts. The main term of TAU is a control object, that is, a certain device for industrial or domestic purposes, some of the parameters of which should be regulated by automation. This can be, for example, a tank in which the liquid level or its temperature must be maintained with a given accuracy. On the block diagram, it is indicated by the letter "A".
The second device needed to create a control loop is a sensor. Without it, it is impossible to judge the state of the system, that is, the value of the output parameter (in our case, the level or temperature). It is indicated by a blue circle.
The third device, without which automation is impossible, is the regulator (β). It can be extremely simple (two-position), as in an iron, for example, or complex, representing an electronic unit with settings, providing a special algorithm (proportional, proportional-integral or proportional-integral-differential). The task of the automatic regulator is to generate a control signal supplied to the fourth and last element of the circuit - the actuator (MI). Whatever the sophisticated scheme of the entire system, if its decisions are not implemented, it will not work. IM is indicated by a white circle, and the signs “+” and “-” symbolize the negative nature of the feedback, that is, the opposite of its action to the direction of change of the output parameter.
Almost all process automation in any production works according to this scheme. Despite the apparent simplicity, it is effective, although it requires a thorough study of all the features of control objects. The fact is that they, like people, react differently to disturbing influences (as automation specialists call different destabilizing factors). First, they all have a lag time. Secondly, the transmission coefficient, that is, the effectiveness of the impact, also varies among different objects. And the speed of "acceleration" for each control channel is different.
After taking characteristics and installing control and management elements, the most crucial stage begins, with which automation is completed. This is setup and setup.