what is contactor in electrical

A contactor is an electrical device used for switching an electrical circuit on or off, and is considered to be a special type of relay. The main difference between a contactor and a relay is that the contactor is used in applications with higher current carrying capacity, whereas the relay is used for lower current applications. Contactors can break current over a wide range of currents, from a few amperes to thousands of amperes, and voltages from 24 VDC to thousands of volts. They are often used to control electric motors, lighting, heating, capacitor banks, thermal evaporators, and other electrical loads. Contactors can be field mounted easily and are compact in size, and generally feature multiple contacts. There are various types of contactors, and each type has its own set of features, capabilities, and applications. Some common types of contactors include knife blade switch, magnetic, and reversing contactors. Contactors are designed with features to control and suppress the arc produced when interrupting heavy motor currents.