31. Why are there four motor contacts for high and low speeds in figure 31-4?L1 L2 L3T2T3H.Two-Speed MotorT11H.T12T13Contral TransformerLowStopTROLOLCACRTRTRHighCACATRO, 31-4 Autcmatic speed control for a two-speed, two winding three-phase motor.

Need of four contacts for high and low speed Motor can be run at low speed and at high speed.

Answered: Why are there four motor contacts for…

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Why are there four motor contacts for high and low speeds in figure 31-4?

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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Concept explainers

Speed control of motor

Speed control by DC motor-speed controller is required to realize variable speed drive. Whenever a motor drives a particular load, it is called drive, and variable speed drive refers to a load requiring variable speed. All this is obtained by a DC motor speed controller.

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31. Why are there four motor contacts for high and low speeds in figure 31-4?
L1 L2 L3
T2
T3
H.
Two-Speed Motor
T11
H.
T12
T13
Contral Transformer
Low
Stop
TR
OL
OL
CA
CR
TR
TR
High
CA
CA
TR
O, 31-4 Autcmatic speed control for a two-speed, two winding three-phase motor.

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L2 L3 T1 T2 T3 Two-Speed Motor T12 T13 Coniral Transtormer Low Stop TR OL OL CA CR TR TR High H. CA TR LAO31- Autcmatic speed control for a two-speed, two winding three-phase motor. 32. Is it necessary to press the stop button when changing from a high speed to a low speed in figure 31-4? Why or why not?