Measurement of Resistance:
Wheatstone’s bridge, sensitivity, limitations. Kelvin’s double bridge. Earth resistance measurement by fall of potential method and by using Megger.
Measurement of Inductance and Capacitance:
Sources and detectors, Maxwell’s inductance and capacitance bridge, Hay’s bridge, Anderson’s bridge, Desauty’s bridge, Schering bridge. Shielding of bridges. Problems.
Measurement of Power, Energy, Power Factor and Frequency:
Torque expression, Errors and minimization, UPF and LPF wattmeters. Measurement of real and reactive power in 3 phase circuits. Errors, adjustments and calibration of single and three phase energy meters, Problems. Construction and operation of single-phase and three phase dynamometer type power factor meter. Weston frequency meter and phase sequence indicator.
Extension of Instrument Ranges:
Desirable features of ammeters and voltmeters. Shunts and multipliers. Construction and theory of instrument transformers, Desirable characterises, Errors of CT and PT. Turns compensation, Illustrative examples, Silsbee’s method of testing CT.
Magnetic measurements:
Introduction, measurement of flux/ flux density, magnetising force and leakage factor.
Electronic and Digital Instruments:
Introduction. Essentials of electronic instruments, Advantages of electronic instruments. True rms reading voltmeter. Electronic multimeters. Digital voltmeters (DVM) - Ramp type DVM, Integrating type DVM and Successive - approximation DVM. Q meter. Principle of working of electronic energy meter (with block diagram), extra features offered by present day meters and their significance in billing.
Display Devices:
Introduction, character formats, segment displays, Dot matrix displays, Bar graph displays. Cathode ray tubes, Light emitting diodes, Liquid crystal displays, Nixes, Incandescent, Fluorescent, Liquid vapour and Visual displays.
Recording Devices:
Introduction, Strip chart recorders, Galvanometer recorders, Null balance recorders, Potentiometer type recorders, Bridge type recorders, LVDT type recorders, Circular chart and recorders. Digital tape recording, Ultraviolet recorders. Electro Cardio Graph (ECG)
Course Outcomes:
At the end of the course the student will be able to:
• Measure resistance, inductance and capacitance using bridges and determine earth resistance.
• Explain the working of various meters used for measurement of Power, Energy & understand the adjustments, calibration & errors in energy meters.
• Understand methods of extending the range of instruments & instrument transformers.
• Explain the working of different electronic instruments.
• Explain the working of different display and recording devices.
Question paper pattern:
• The question paper will have ten questions.
• Each full question is for 20 marks.
• There will be 2 full questions (with a maximum of three sub questions in one full question) from each module.
• Each full question with sub questions will cover the contents under a module.
• Students will have to answer 5 full questions, selecting one full question from each module.
Text Books
1 Electrical and electronic Measurements and Instrumentation A.K. Sawhney Dhanpat Rai and Co 10th Edition
2 A Course in Electronics and Electrical Measurements and Instrumentation J. B. Gupta Katson Books 2013 Edition
Reference Books
1 Electrical and electronic Measurements and Instrumentation R.K. Rajput S Chand 5th Edition, 2012
2 Electrical Measuring Instruments and Measurements S.C. Bhargava BS Publications 2013
3 Modern Electronic Instrumentation and Measuring Techniques Cooper D and A.D. Heifrick Pearson First Edition, 2015
4 Electronic Instrumentation and Measurements David A Bell Oxford University 3rd Edition, 2013
5 Electronic Instrumentation H.S.Kalsi Mc Graw Hill 3rd Edition,2010