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What are electrical switches?

Switches are devices that open and close electrical circuits.

Light switches are used every day. They are usually physical buttons on the wall; however, there are digital switches with advanced technologies that are suitable for energy optimization; they can work manually, with Wi-Fi, and even with automatic sensors.

What are the essential parts of an electrical switch?

  1. Actuator, which allows opening or closing the electrical circuit.
  2. Push button, which exerts pressure on the actuator, letting the contacts hold together.
  3. Paths, which control electrical circuits from different places.
  4. Poles or circuits, which represent the receiving points of the current.  

How do electrical switches work?

At the mechanical level, the switches have two metal contacts which are separate but united through a moving part called an actuator. The actuator presses on the contacts to hold them together and allow or block the passage of current.

Its function is to facilitate switching an electrical system on and off. When the circuit is open, the current can flow; on the contrary, when it is closed, the flow is interrupted.

As for cables, the switches have a phase line input and output. The electric cable, in turn, is composed of three wires: the hot, neutral, and ground wires, all covered by an insulation material. The wire connects to the electrical switch, which controls it, as well as to the source of electricity. Once these connections have been made, the switch fulfills the function of enabling or disabling the passage of electrical energy.

Electrical switches can also work for creating parallel and interconnected circuits, which can be manipulated by specific sockets; this means it is possible to have different electricity distribution points.

What types of electrical switches are there?

Although all electrical switches perform the basic function of opening or closing electrical power circuits, there are different types. The main ones are:

  • Three-way switches: they connect with each other to turn the electric current on or off; each works depending on the other.
  • Crossed switches: three switches connected to each other and which operate electric light from any point where the individual switches are located.
  • Stop switch: industrial in nature and works to stop an operation, whether in an emergency or not.
  • Rocker switch: one of the most common types of switches. It has an actuator that, depending on the direction in which it is placed, activates or cuts off the electrical power.
  • Transfer switch: transfers the energy load from one circuit to another in the event of an emergency power failure. It is often used in electrical and industrial substations.
  • Circuit breaker: this type of switch cuts off the power automatically if an overload or short circuit occurs. It is often used in homes, shops, and industries.
  • Differential switch: provides protection against current leakage due to faulty insulation. They are very sensitive and easily detect changes in current.
  • Reed switch: works by means of a magnetic field; is encapsulated in a vacuum-sealed glass tube.
  • Insulated circuit breaker: uses a large amount of amperage for its operation. 
  • Momentary switch: works as long as there is pressure on the actuator.
  • Rotary switch: activated by turning a knob.
  • Centrifugal switch: activated based on a centrifugal force. When the rotating body reaches a certain speed, the switch is activated, and when it stops, it turns off.
  • DIP Switch (Dual in Line Package): a set of micro-switches connected to each other in circuits that change the behavior of an electronic device.
  • Mercury switch: electricity is conducted by a small amount of mercury inside a glass tube that is hermetically sealed and is activated or deactivated by tilting.
  • Membrane switch: located on printed circuits, that is, on a surface of paths of conductive material on a non-conductive base. In addition, they are usually used in remote controls, microwave control panels, and more.
  • Dimmer switch: varies light intensity by means of a rotating knob.

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