Contactors are one of the most important elements in the electrical control system. They are basically a type of relay that can control circuits and voltages up to a higher power level than a typical electromechanical relay. They have a wide variety of applications, such as controlling lighting, motors and various other electrical loads. Contactors contain an electromagnet with an armature, which when energized opens or closes a set of contacts. The contacts can be connected to the load, allowing it to be turned on or off. Contactors are used for high-amperage operation, and can handle much higher current ratings than normal switches or relays. They are also very useful in motor control applications, where the motor can be turned on or off at different times.