It is not advisable to start induction motors of higher ratings (generally above 25kW) directly from the mains supply. Various starting methods of induction motors are described below.| www.electricaleasy.com
Crawling and cogging both are particularly related to squirrel cage induction motors. Sometimes, squirrel cage induction motors exhibits a tendency to run at very slow speeds (as low as one-seventh of their synchronous speed). This phenomenon is called as crawling of an induction motor.| www.electricaleasy.com