Increasing the endurance of fuseless load feeders by using larger contactors
Can larger contactors than the types listed in the tables of the following publications be used for the purpose of increasing the electrical endurance of fuseless motor feeders with type of coordination 2? *Configuration manual "SIRIUS Configuration – Selection Data for Fuseless Load Feeders" * and *Configuration manual "Configuring SIRIUS Innovations" *
ANSWER:Since the dynamic response of different types of contactors varies greatly, only the contactor tested in combination with the motor starter protector may be used. As a rule, the contactors required for type 2 have been designed to perform over and above the switching capacity (AC-3) defined for this type, thus already ensuring increased electrical endurance.