EI 1251 ELECTRICAL MEASUREMENTS AND INSTRUMENTS 3 1 0 100
AIMTo provide adequate knowledge in electrical measurements and instrumentation.
OBJECTIVES
To make the students to gain a clear knowledge of the basic laws governing the
operation of electrical instruments and the measurement techniques.
i. Emphasis is laid on the meters used to measure current & voltage.
ii. To have an adequate knowledge in the measurement techniques for power and energy, power and energy meters are included.
iii. Elaborate discussion about potentiometer &
instrument transformers.
iv. Detailed study of resistance measuring methods.
v. Detailed study of inductance and capacitance measurement.
1. MEASUREMENT OF VOLTAGE AND CURRENT 9
Galvanometers – Ballistic, D’Arsonval galvanometer – Theory, calibration, application – Principle, construction, operation and comparison of moving coil, moving iron meters, dynamometer, induction type & thermal type meter, rectifier type – Extension of range and calibration of voltmeter and ammeter – Errors and compensation.
2. MEASUREMENT OF POWER AND ENERGY 9
Electrodynamometer type wattmeter – Theory & its errors – Methods of correction – LPF wattmeter – Phantom loading – Induction type KWH meter – Calibration of wattmeter, energy meter.
3. POTENTIOMETERS & INSTRUMENT TRANSFORMERS 9
DC potentiometer – Basic circuit, standardization – Laboratory type (Crompton’s) – AC potentiometer – Drysdale (polar type) type – Gall-Tinsley (coordinate) type – Limitations & applications – C.T and V.T construction, theory, operation, phasor diagram, characteristics, testing, error elimination – Applications.
4. RESISTANCE MEASUREMENT 9
Measurement of low, medium & high resistance – Ammeter, voltmeter method – Wheatstone bridge – Kelvin double bridge – Ductor ohmmeter – Series and shunt type ohmmeter – High resistance measurement – Megger – Direct deflection methods – Price’s guard-wire method – Loss of charge method – Earth resistance measurement.
5. IMPEDANCE MEASUREMENT 9
A.C bridges – Measurement of inductance, capacitance – Q of coil – Maxwell Bridge – Wein’s bridge – Hey’s bridge – Schering bridge – Anderson bridge – Campbell bridge to measure mutual inductance – Errors in A.C. bridge methods and their compensation – Detectors – Excited field – A.C. galvanometer – Vibration galvanometer – Introduction to cable fault and eddy current measurement.
L = 45 T = 15 Total = 60
TEXT BOOKS
1. E.W.Golding & F.C.Widdis, ‘Electrical Measurements & Measuring Instruments’, A.H.Wheeler & Co, 1994.
2. A.K. Sawhney, ‘Electrical & Electronic Measurements and Instrumentation’, Dhanpath Rai & Co (P) Ltd, 2004.
REFERENCE BOOKS
1. J.B.Gupta, ‘A Course in Electronic and Electrical Measurements and Instrumentation’, S.K. Kataria & Sons, Delhi, 2003.
2. S.K.Singh, ‘Industrial Instrumentation and control’, Tata McGraw Hill, 2003.
3. H.S.Kalsi, ‘Electronic Instrumentation’, Tata McGraw Hill, 1995.
4. Martia U. Reissland, ‘Electrical Measurement’, New Age International (P) Ltd., 2001.