A moving coil milli-voltmeter has a resistance of 200 Q and the full scale deflection is reached when a potential difference of 100 mV is applied across the terminals. The moving coil has effective dimensions of 30 mm × 25 mm and is wound with 100 turns. The flux density in the air gap is 0.2 ob/m². Determine the control constant, if the final deflection is 100° and a suitable diameter of copper wire for coil winding if 20% of the total instrument resistance is due to the coil winding. Resistivity of copper is 1.7 × 10N-m.

A moving coil milli-voltmeter has a resistance of 200 Q and the full scale deflection is reached when a potential difference of 100 mV is applied across the terminals. The moving coil has effective dimensions of 30 mm × 25 mm and is wound with 100 turns. The flux density in the air gap is 0.2 ob/m². Determine the control constant, if the final deflection is 100° and a suitable diameter of copper wire for coil winding if 20% of the total instrument resistance is due to the coil winding. Resistivity of copper is 1.7 × 10N-m.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

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