A contactor is an electrical switching device used to control and manage the flow of electric current in industrial and commercial applications. It is essentially a heavy-duty relay that is designed to handle high currents and voltages. Contactors are commonly used in machinery, motors, lighting systems, heating and cooling systems, and other electrical equipment.
Contactors consist of an electromagnetic coil that, when energized, generates a magnetic field. This magnetic field pulls down a set of contacts, which allows the current to flow through the device. When the coil is de-energized, the contacts return to their original position, interrupting the current flow.
Contactors are designed to handle frequent and high-load switching operations, which makes them suitable for controlling larger electrical loads that standard relays might not be able to handle. They play a crucial role in industrial automation and are often controlled by programmable logic controllers (PLCs) or other control systems.
It's important to note that contactors are distinct from relays primarily in terms of their capacity and intended usage. Contactors are built to handle higher currents and are generally used in industrial and heavy-duty applications, while relays are used for lower-power applications and signal switching.