Principle of electromagnetic contactor

The electromagnetic contactor acts as an automatic switch that connects or disconnects a load-carrying AC/DC main circuit or a control circuit of great capacity. When the contactor's electromagnetic coil is energized, it generates a powerful magnetic field that attracts the armature and drives the contact action. As a result, the normally closed contact is disconnected, and the normally open contact is closed. The opposite occurs when the coil is de-energized, and the armature is released by the release spring, restoring the contacts' position. The contactor's applications are quite extensive, with current ratings ranging from 5A to 1000A. It is commonly used in electrical engineering to control motors and other electrical loads like electric heating adapters, welding machines, and lighting equipment. The contactor not only helps connect and disconnect circuits but also has a low-voltage release protection feature. The contactor's large control capacity makes it suitable for remote control and frequent operation, and it is a critical component in an automatic control system.