Contactors are heavy-duty electromagnetic switches that are normally used in controlling large lighting loads and motors. They operate similar to relays, but often times deal with more voltage, higher amperage, and have more input and output options.

CONTACTORS

Contactors are extremely useful pieces of equipment that allow switching of several different circuits at the same time. They are flexible for logic controlling as well, so you can use many contactors for turning things off WHILE turning other things on at the same time. This is similar to how control relays work, except that with contactors you generally have larger coils, bigger contacts, and can control much larger loads than a typical relay could handle.

THE COIL

A contactor works similar to a light switch, however rather than needing to manually touch the switch to turn it on/off, you send current to the coil inside and that acts as your switch. The inside of the contactor has 2 large iron cores that are spaced apart from one another, with a coil of copper wire wrapped around them. When current is sent to this coil of wire, the iron cores slam together (as an electromagnet is created) and the contacts of the contactor either open or close…or both at the same time depending on which type you have.

Coils

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