Auxiliary contacts are electromechanical devices used in electrical circuits for controlling the circuits that are opened and closed by the main contacts. They are often used in conjunction with contactors and buttons in industrial applications.

Contactors are electromechanical switches designed to control large currents in electrical circuits used in industrial applications. They are composed of different parts, including main contacts and auxiliary contacts, and are used to control the flow of large currents.

Buttons, on the other hand, are small electromechanical devices used in electrical circuits. They are often used to open or close a circuit when they are pressed. Buttons are commonly used in industrial machinery.

Auxiliary contacts provide additional functions for contactors and buttons. For example, auxiliary contacts can be used to indicate the status of a contactor or whether a button is open or closed. These devices are an important component for safe and efficient operation of industrial machinery and other electrical circuits.