Command circuit. Know what it is and what its application is!

Everything around us involves electricity, whether at home, on the street, at school, at work, in the means of transport, within the industry or practically everywhere, for example when turning on electrical equipment, the activation of electronic gates, elevators, presence sensors, city streetlights, traffic signs, electric machines and motors and so on! But, have you ever stopped to think about how it all works?

Some of those mentioned above are triggered by electrical commands. We will clarify what is electrical commands, what is the application of electrical commands, some symbologies of electrical commands and their components, come on guys!

Of course, all the equipment, devices and machines mentioned above work with electricity, but how are some of them activated? Applications for electrical controls go far beyond the industry, but to better understand, let’s understand what electrical controls are.

What is it and what are the applications of electrical controls:

Electrical controls are the connection circuits for electrical machines and loads and thanks to their logic of commands, drives and with the advancement of technology today we have even faster and more efficient production processes and certainly advances that facilitate and streamline our daily lives.

It is understandable that with the advancement of technology, electric controls have lost space in certain areas, but we cannot think of electric controls only within the industry, we may perhaps have electric controls closer than we can imagine, such as some models of elevators, which they use electric controls to start the engines or in certain hotels, when the room only has power when a card is inserted.

The main function of electrical controls is to drive electrical machines and electrical equipment, through their drives and command logic, such as three-phase motors, lathes, milling machines, moving walkways and infinite production processes within and outside industries.

For you to see that electric controls have a multitude of application possibilities, we can start the engines, starting with a star, a triangle, reversing the engine, making an elevator, traffic lights, production processes through electro pneumatics and hydro pneumatics, among other activities, which will depend on the application.

But to be very clear, these are possible applications, such as traffic lights for example, it is not at all feasible to build a traffic light with electrical controls, due to the space to accommodate the components and the quantity, costs, maintenance and among other reasons.

Load circuit:

Electrical controls are basically divided into two modules or circuits, which are defined as load circuits and command circuits. The load circuit is responsible for accommodating equipment that has greater power, such as electric motors. This circuit can be single-phase, two-phase or three-phase, which will depend on the load connected to it. It is important to highlight that as the load circuit is the one that dissipates the most power, it is there that the greatest amount of electric current passes.

Command circuit:

The command or control circuit, on the other hand, is where the actuation and signaling devices are found, this place is where it has a combination of elements that execute the activation of the loads and signalers through a logical combination of the elements of this circuit, that is, in electrical commands the command or control circuit is where it passes and supports the smallest electric current in the circuit.

Here on the website, we have articles that show and explain in detail the components and devices of electrical controls, such as contactorsfusesrelays, and signals, for example.

Command circuit for connecting two signalers.

We will show and explain in a simple way a logic of activation for two traffic lights or lamp, so that both cannot be connected at the same time, that it has a button that turns off the two lamps, and that both hands are used to activate them, as shown in the diagram below. But, remember that this is a simple project, but that the logic can be used for other purposes, such as safety methods for the operators of a machine for example.

This circuit contains two contactors (K1 and K2) with normally closed (NC) and normally open (NO) contacts, two signals, one green and one red and four buttons (S0, S1, S2, and S3), so that S0 is responsible for switching off the circuit, S1 is the safety button, that is, to activate any of the signal lights, it must be pressed together with one of the other buttons, which are S2 and S3 responsible for activating contactors K1, K2 respectively, that is, it is these contractors that will be responsible for keeping the green (H1) and red (H2) lamps on or off.