Protection Relays

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. Square D contactors are used in applications with higher current carrying capacity, typically built for and used in 3-phase applications. Telemecanique 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. Schneider Electric TeSys contactors and relays are available for both NEMA and IEC applications, and are certified by major standards around the world.