8. What conditions must be fulfilled for the self-excitation of a d.c. shuntgenerator?The open-circuit characteristic of a shunt-excited d.c. machine, runat 1200 rev/min, is:Terminal voltage (V)Field curreat (A)47 85 103 114 122 127 135 1410-2 0-4 0-6 0-8 1-0 1-2 1-6 2-0The field coil resistance is 55 A. Determine: (i) the value of thefield-regulating resistance to enable the machine to generate 120 V onopen circuit when run at 1200 rev/min; (i) the value of the open-circuitvoltage when the regulator is set to 20 A and the speed is reduced to800 rev/min.

field coil resistance = 55 ohm speed of the shunt excited dc machine = 1200 rev/min

8. What conditions must be fulfilled for the self-excitation of a d.c. shunt generator? The open-circuit characteristic of a shunt-excited d.c. machine, run at 1200 rev/min, is: 47 85 103 114 122 127 135 141 Terminal voltage (V) Field curreat (A) 02 04 06 08 1-0 1-2 1-6 2-0 The feld coil resistance is 55 A. Determine: 6) the value of the field-regulating resistance to enable the machine to generate 120 V on open circuit when run at 1200 rev/min; (ü) the value of the open-circuit voltage when the regulator is set to 20 A and the speed is reduced to 800 rev/min.

8. What conditions must be fulfilled for the self-excitation of a d.c. shunt generator? The open-circuit characteristic of a shunt-excited d.c. machine, run at 1200 rev/min, is: 47 85 103 114 122 127 135 141 Terminal voltage (V) Field curreat (A) 02 04 06 08 1-0 1-2 1-6 2-0 The feld coil resistance is 55 A. Determine: 6) the value of the field-regulating resistance to enable the machine to generate 120 V on open circuit when run at 1200 rev/min; (ü) the value of the open-circuit voltage when the regulator is set to 20 A and the speed is reduced to 800 rev/min.

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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