3.50.2 Principle
The locked-rotor protection automatically exits during the starting process of the motor, and is
automatically put into operation after starting. It is used for the locked-rotor protection that occurs
during the normal operation of the motor. The locked-rotor protection current is composed of
positive sequence current, with IA1, IB1, and IC1 being the positive sequence current of the
terminal current. The locked-rotor protection time is set according to the maximum allowable
locked-rotor operation time.