8.A. One characteristic of a typical universal motor is that it A. is usually designed for low-speed operation. B. has a low locked-rotor torque. C. operates at about the same speed on a-c and doc circuits. 8.B. A centrifugal starting switch in a split-phase motor operates on the principle that A. a high starting current opens the switch contacts. B. a higher speed changes the shape of a disk to open the switch contacts. C. the actuating weights move outward as the motor slows down.

8.A. One characteristic of a typical universal motor is that it A. is usually designed for low-speed operation. B. has a low locked-rotor torque. C. operates at about the same speed on a-c and doc circuits. 8.B. A centrifugal starting switch in a split-phase motor operates on the principle that A. a high starting current opens the switch contacts. B. a higher speed changes the shape of a disk to open the switch contacts. C. the actuating weights move outward as the motor slows down.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 19RQ: Why is the starting torque per A of starting current of a wound-rotor motor higher than that of a...

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