Contactor starter kits
The contactors are designed for shunting switching on and off of operating currents in the event of a large number of switching operations. Due to the usually low short-circuit strength, the contactor must cooperate with fuses that increase the short-circuit strength, but also limit the operating currents of the contactor-fuse set due to low rated currents of the fuses. When selecting a contactor to work in a specific place of the network, the same criteria as in the case of disconnectors should be used, taking into account the required durability and switching frequency. The category includes contactors enabling the start of three-phase motors, reacting to the failure of one of the phases, which may be harmful to the motor.