Why are limit switches needed and what types are they?

Limit switches, or as they are also called limit switches, are used to interconnect an electrical circuit, for example, in electrical appliances and alarm systems. Also, these devices are used to control and manage electrical engineering, which is systematically checked for mobility. The switch is mounted on the structure itself where it is necessary to control the movement of individual elements. To use the limit switch, you need to know what it is for, what types it happens and how each individual version works. This is what will be discussed later.

Content:

Circuit breaker design
Varieties
Features of work
Application area

Circuit breaker design

The composition of this device includes the following components:

panel;
housing;
contacts;
head.

It is very important that the switch case has good strength, that the device is stable and can withstand various mechanical influences on the case. Manufacturers use aluminum-silicon alloy as a material, and some types of limit switches are made of durable plastic.

The design of the limit switches is examined in detail in the video:

Varieties

It is important to know what the limit switches are, because without this knowledge it will be difficult to choose the right device. These switching devices are divided into several main types:

Non-contact. This device is triggered in the event of the approach of any metal or other object on which switching was made in advance.
Mechanical. They work only with mechanical action on the wheel or on the lever. As a result, the contacts either close or open, thereby giving a control or warning signal.
Magnetic. They are also called reed switches. Based on the name, you can understand that the device is triggered when a magnet approaches it at a certain distance.

Contactless limit switches are more modern than mechanical ones. They work on a special transistor key, which in the open position has little resistance.

All proximity switches are divided into four groups:

Inductive. The limit switch is triggered when the sensor detects a metal object. At the moment of detecting the metal, the inductive resistance increases, due to this the current in the winding decreases, and thus the contacts in the circuit open. The assortment of these products is very large and diverse, so you can easily pick up the right size.
Capacitive, interact with the human body. When a person approaches the sensor, an electric capacitance arises, due to which the circuit of the multivibrator installed inside the device is brought into operation. The closer a person is, the lower the pulse frequency becomes, and the capacity becomes larger. The main function is performed by the plate, which is connected to the capacitor.
UltrasonicQuartz sound emitting elements are used. When something appears in the range of the device, the amplitude of the sound signal changes, basically this purity is inaudible to people.
Optical switches have a special transistor and an infrared LED. When the LED beam is interrupted, the photocell closes.

The video below shows some types of limit switches:

Features of work

The limit switch has a certain principle of operation, thanks to which it is started and driven. The switching device will operate at the moment of connection with the restored limiter, at this moment the power supply to the electrical equipment is cut off. It is very important that all elements of this device work reliably and correctly, performing all the necessary commands. At the same time, everything should work flawlessly, regardless of the type, configuration of the device and the way it is connected. That is why the scope of the limit switch is in places of particular danger.

At the moment of contact of the movable mechanism with the device of the limit switch, it gives a signal. This will indicate that there is a danger in the electrical circuit. This device is a sensor equipped with an automatic shutdown system.

Application area

You also need to know where the limit switches are used. Each type of performance has its own specific purpose, and are used in different fields of activity. However, according to their use, they are divided into:

Functional. They are responsible for regularly turning the lights off or on, or some other electrical device. For example, such a device is in the refrigerator. When the door is opened, the mechanism turns on the light, and when closed, it turns it off, this is one of the options for using the limit switch.
Protective. They are mounted in order to protect both the mechanism and workers from improper actions. For example, a miner's elevator will not begin to descend until the doors are closed, so people can use the elevator safely.

To summarize, the use of this device depends on the design and capabilities of the mechanism. Often consumers do not even know that they often have to use this mechanism in life:

in the automotive industry and in the car;
in household appliances and household;
in furniture products;
in factories and manufacturing enterprises to carry out various tasks.

Limit switches are very practical and necessary devices. But to connect such devices it is better to seek the help of specialists. As it has already become clear, these devices greatly simplify the use of many household items. We hope the provided article was useful and interesting for you!

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