What are Limit switches? Advantages, disadvantages

What are limit switches?

Limit switches are a type of switch that is equipped with a valve that functions to replace the button. The limit switch working principle is the same as the Push ON switch which will only connect when the valve is pressed at a specified pressure limit and will break when the valve is not pressed.


Limit switches are included in the category of mechanical sensors, namely sensors that will provide electrical changes when there is a mechanical change in the sensor. The application of the limit switch is as a sensor the position of an object (object) that moves.

Where Limit switches are used?

Limit switches are generally used to: Decide and connect a circuit using other objects or objects. Turn on large power, with small facilities. As a sensor position or condition of an object. The limit switch working principle is activated with an emphasis on the button on the boundary / area that has been determined beforehand so that the circuit breakdown or connection occurs. The limit switch has 2 contacts, namely NO (Normally Open) and NC contact (Normally Close) where one contact will be active if the button is pressed. The limit switch construction and symbol can be seen as shown below:


Mechanical limit switches are contact sensing devices widely used for detecting the presence or position of objects in industrial applications.

Advantages of limit switches:

  • Suitable for all industrial environment

  • Precise in terms of accuracy and repeatability

  • Needed less energy

  • Can switch loads with high inductance

  • Can control multiple loads

Limitations of Limit Switches:

  • Generally restricted to equipment operating at relatively low speeds.

  • Must make direct contact with target.

  • Moving mechanical parts will wear out