Found on most electrically powered motors, a Magnetic contactor is a form of electrical relay. To balance out or homogenize changes in electrical frequency which may come for direct power sources and high-load an electrical motors and from a power supply as well as to act as a safeguard they act as a go-between. One should keep in mind that though they are similar in design still magnetic contactors cannot be referred to as circuit breakers. During a short circuit, they do not serve the connection between appliance, and power source.

The exterior portion of the magnetic contactor is square and boxlike. It can be small enough to fit in the hand or over a yard in length but everything relies on the electrical device to which it attaches. They are composed of heat-resistant, non-conductive plastic such as Bakelite, and have two metal contacts that fit into the contacts of their parent device. Inside it, there is one contact that leads to a small electromagnetic coil. The other contact leads to a soft iron core that remains separated from the coil because of a spring.

For repeatedly making and breaking branch circuits magnetic contactors are that provide a safe and convenient means and these are electromagnetically operated switches. Between a contactor and a motor starter, the principal difference is that contactor does not contain overload relays. With a pilot control device, electric contactors are used to switch, such loads as lighting, heating, and controlling electric motors where overload protection is provided separately.