1. The armature windings of a dc motor have a resistance of 5.0 Ω. The motor is connected to a 120 V line and when the motor reaches full speed against its normal load, the counter emf is 108 V. Calculate: a. The current into the motor when it is just starting up. Be sure to draw the equivalent circuit showing your motor as a resistor, the battery, and the back emf (another battery) if it exists b. The current when the motor reaches full speed. Be sure to draw the equivalent circuit showing your motor as a resistor, the battery, and the back emf (another battery) if it exists.

1. The armature windings of a dc motor have a resistance of 5.0 Ω. The motor is connected to a 120 V line and when the motor reaches full speed against its normal load, the counter emf is 108 V. Calculate: a. The current into the motor when it is just starting up. Be sure to draw the equivalent circuit showing your motor as a resistor, the battery, and the back emf (another battery) if it exists b. The current when the motor reaches full speed. Be sure to draw the equivalent circuit showing your motor as a resistor, the battery, and the back emf (another battery) if it exists.

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 2PA: You have been given the task of connecting a nine-lead three-phase dual-voltage motor to a 240-V...

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