Electrical Instruments and Measurements PDF

A COURSE IN ELECTRICAL AND ELECTRONIC ~/IEASUREMENTS AND INSTRUMENrATIC>N.. ·.... By A. K. SAWHNEY M.Sc. (E11gg.) Professor of Electric...

A COURSE IN ELECTRICAL AND ELECTRONIC ~/IEASUREMENTS AND INSTRUMENrATIC>N.. ·.... By A. K. SAWHNEY M.Sc. (E11gg.) Professor of Electrical E11gineeri11g Tbapar Engineering College, PATIA LA DHANPAT RAI & SONS EDUCATIONAL AND T}tCHNICAL PUBLISHERS 1682,.Nai Sara~, Delhi-U0006 Phone : 265367 ~-· @All rights rese,frcd by, the author. No parts of this publication may be reproduced', stored in re;rieval.$ystem., ot· transmitted, ibany.form or by a~y ~eans, elect~onic, mecha6ical, photocopying, recording, or o herwise, wi~h~~t the prior wri~ten permissio.1 of the autho~.anJ the publisher.. , ·. ·. "· By tbe Same ~uthor 1. A Course in Electrical Machine Design. 2. A Course in Mechanical Measurements and Instrumentation. First. E.aitjfn, 1 : 1973 I S,etond F.d!tfon :.1976 Reprint. : 1978 \Rtprint. : 1979 Reprint : 1980.Third B/iition : 1981 (Modified and Enlarged). Repriri/ : 1982 Fburtij Editfon : '1983· Reprinted· 1984 , Reprint ,i'1 ·· 1'85 I Compile~ b)' : Smt. ~hand~r Sawhney Pl,lblished by : J.C. Kapur', fqr Dhanpat Rai & Sons, Delbi"l10006 (H.o. JuUundur).. ctmposed by : Karan P1ibtio1·Sr.cv'ice, Subhash Park, Shahdara, Delhi·l1Qo3f. Printed at 1. D.R., Prilltloj Service, Panch.sheeJ Garden, ShahdAta, DeJhH 10032/  Preface to the· Fourtn 1:arc1on. 'The author i~ pleased to brfogi out the Fourth Editiori of the book a.ncf is _fhankful t~· both· teachers and students for their affecfi-0nate and warm receptio:n to the thlfd ed1t~n of the boo~ whJ9h has been sold out in a period of less than one year. The present edit.ion retai~s essentially the same subjectmatter as the third edition. However, the typographical and (\ther.errors, which had crept in earlier edition, have been corre.cted. The book is intended as a stand~rd text for students studying for their first de8ree i. Electrical, Electronics and lhstrumentation Engineering at ~ndian Universities (}nd abroad, qd· also for those appearing for A.M.l.E. section Band other profession~l examinations. The book is equally useful for postgraduate students as well as practising engineers involved in ihe iel4A of Measurements and Instrumentation. 1 · There have been significant changes in curriculum of almost all the upiversities in recent years. Electrical and Electronic In,strumentation is now offered· as separate paper in maay universitks. This has been necessitated on account of latest technological advances which put greater emphasis and reliance on Electronic Instrumentation... The contents of the book have been· drastically modified,.re-arrange~ an9 updated t9 · acquaint the reader of modern trends in the field: pf_ Measurements and Instrumeµtation. _. , The bobk has b.een divided into two parts. -i Part I d~aJs with Mea.surements.and Measuriq Instruments and Part II takes care of the Instrmnentat1on. There 1s an extensive coverage 4f Electrical and Electronic Instrumentation in this edition of the book as compared with the earlier ones. The coverage of Instrumentation portion is about 500 pages · out of a total of nearly 1200 pages. The subject of ·Instrumentation has been developed in logical steps. Separate ahapteu are devoted to topics like Generalized Measurement Systems, Transducers, Signal Conditioning, Data Transmission and Telemetry, Display Devices and Recorders, Measurement of Non· electrical, Quantities and Data Acquisition Systems. Also there are additional chapters on static and dynamic characteristics of Measurement Systems. There is an increased emphasis on digital instrumftlnts and instrumentation which is constant with the present trends. ·.· There are.three Appendices in the book. Appendix A deals with Number Systems, Appendix B with Logic gates and Appendix C with conversions from various system~ of units to S.I. The significant additions to the measurements· portion are Transformer ratio bridges (wliich are fast replacing the conventional four arm a.c. bridges), spectrum analyzer, vector impedance meter, vector meter, digital maximum demand indicator and Hall effect multiplier to name a few..The book ,in fact covers a very wide spectrum of the_Jield of Electrical and Electro1io Measurements ?.nd Instrumentation and.is a conlplete reference in. itself. Another outstanding feature of the book is the i~clusion Qf over 400 1solveQproblems which· ill addition to linking the theory with actual applications gives an insight of the industrial practieo. Also about 300 unsolved problems (with answers) have been included to give the students practiee in solving problems.. The author considers the inclusion of problems on Instrumentation (both· ''solved and uB.l ~~ved) as a speciality of this book. This is a pioneering effort which is the outcome of cuthor's, experience of teaching the subject for almost two decades. The book though voluminous, covers two papers, i.e., first on Electrical and Ele~tronie: Measurements and Instruments and second on Electrical and Electronic Instrull_1entat\Qn.arid thus fully justifies its volume. SI units have been uniformly used in.the book throughout. 1 · The autho'r will feel highly obliged to·all the readers for their constructive suggestions aQd healthy criticism of the book which will go a long way in the improvement of the text. - ,· The author is thankful to his wife, Chander J for render,ing assistance in the compilation Qd editing of the work. · · ··.. ' · The author is grateful to his brothers, Ravish a~d Ajay, for their constant help durinatlae: p~eparatiQn of tqe text. - ·· · I To... aut~or;s parents who have ~~en~ s~urce of encourascment and guidance. PATIALA 26-9-1.984 ' ~. A..K. S.A.WQlf -· -- _.,.,,.,, >"'  ' '