Q23. A PMMC Ammeter has a coil of effective depth of 5 cm and a width of 20 mm, thecoil has about 150 turns, and it has coil resistance of 20 ohms. The flux spread inthe air gap is done at density of 100mWb/m². Then calculate,i. Control torque produced by the coil, when it measures 15 A.ii. Spring constant, when it measures 15 A and deflects by an angle of 30°ii.Deflection torque exerted on the pointer, when it measures 20 A.Analyze the relationship between the area of moving coil and deflectiontorque produced in a PMMC instrument.iv.

The deflecting Torque Td for a PMMC instrument is given as: Td=BINA where, B is the magnetic flux, I…

PMMC Ammeter has a coil of effective depth of 5 cm and a width of 20m il has about 150 turns, and it has coil resistance of 20 ohms. The flux sp e air gap is done at density of 100mWh'm'. Then calculate, Control torque produced by the coil, when it measures 15 A. Spring constant, when it measures 15 A and deflects by an angle of 3 Deflection torque exerted on the pointer, when it measures 20 A. Analyze the relationship between the area of moving coil and det torque produced in a PMMC instrument.

PMMC Ammeter has a coil of effective depth of 5 cm and a width of 20m il has about 150 turns, and it has coil resistance of 20 ohms. The flux sp e air gap is done at density of 100mWh'm'. Then calculate, Control torque produced by the coil, when it measures 15 A. Spring constant, when it measures 15 A and deflects by an angle of 3 Deflection torque exerted on the pointer, when it measures 20 A. Analyze the relationship between the area of moving coil and det torque produced in a PMMC instrument.

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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