Two series motors are exactly alike in construction except that the air gap of one is slightly greater than that of the other. When taking 70 A at 600 V, one motor runs at 800 rpm and the other at 850 rpm. If the two motors are mechanically coupled and connected in series across 600 V, at what speed will they run when the current is 70 A? Total resistance of each motor is 0.28 ohm.

Two series motors are exactly alike in construction except that the air gap of one is slightly greater than that of the other. When taking 70 A at 600 V, one motor runs at 800 rpm and the other at 850 rpm. If the two motors are mechanically coupled and connected in series across 600 V, at what speed will they run when the current is 70 A? Total resistance of each motor is 0.28 ohm.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter3: Magnetic Starters

Section: Chapter Questions

Problem 21SQ

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