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Contactor
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<p><a href="/facts/Thumb/vx1ycnbA">thumb</a> </p> <p>A contactor is a special type of relay used for switching an electrical circuit on or off. Contactors and relays function in very similar way, with the main difference being the loads they are designed to handle. Contactors are used in applications with higher current carrying capacity, typically built for and used in 3-phase applications. Contactors are most commonly used with electric motors and lighting applications. Relays are used for lower current or low voltage switching, more commonly used in single-phase applications. A contactor joins 2 poles together, without a common circuit between them. A relay has a common contact that connects to a neutral position. As the largest selling line of contactors in the world, Schneider Electric TeSys product line provides high reliability with long mechanical and electric life. TeSys contactors and relays are available for both NEMA and IEC applications, and are certified by major standards around the world. </p><p>Unlike general-purpose <a href="/facts/Relay/NQcb9usW">relays</a>, contactors are designed to be directly connected to high-current load devices. Relays tend to be of lower capacity and are usually designed for both <i>normally closed</i> and <i>normally open</i> applications. Devices switching more than 15 amperes or in circuits rated more than a few kilowatts are usually called contactors. Apart from optional auxiliary low-current contacts, contactors are almost exclusively fitted with normally open ("form A") contacts. Unlike relays, contactors are designed with features to control and suppress the arc produced when interrupting heavy motor currents. </p><p>Unlike a <a href="/facts/Circuit_breaker/vbw6cWSe">circuit breaker</a>, a contactor is not intended to interrupt a <a href="/facts/Short_circuit/r09vaaeQ">short circuit</a> current. Contactors range from those having a breaking current of several amperes to thousands of amperes and 24 V DC to many kilovolts. The physical size of contactors ranges from a device small enough to pick up with one hand, to large devices approximately a meter (yard) on a side. </p><p>Contactors are used to control <a href="/facts/Electric_motor/ArD7BGDa">electric motors</a>, <a href="/facts/Electric_lighting/v3fb5WBp">lighting</a>, <a href="/facts/Electric_heating/Lx6n0WCC">heating</a>, <a href="/facts/Capacitor/hyowqv7n">capacitor</a> banks, thermal evaporators, and other electrical loads. </p>