December 17, 2011

ELECTRICAL TECHNOLOGY ECE JNTU previous years question papers

ELECTRICAL TECHNOLOGY JNTU previous years question papers

 Time: 3 hours Max. Marks.80

Answer any Five questions

All questions carry equal marks

1.a) Explain briefly the essential functions of armature and field coils in a dc machine.
b) Develop an expression for EMF in a dc machine.
c) A 4 pole, long shunt, lap wound generator supplies 25 Kw at a terminal voltage of 500 V. The armature resistance is 0.03 O, series field resistance is 0.04O and shunt field resistance is 200O. The brush drop is IV. Determine the emf generated. [16]

2.a) Discuss the various methods of speed control of a D.C motor?
b) A 2- pole, D.C. shunt motor operating from a 200 V supply takes a full load current of 35 Amps drawn from the supply. The no load current being 2 Amps. The field resistance is 500O and the armature resistance is 0.6O. Calculate the efficiency of the motor on full load. [8+8]

3.a) Explain the principle of operation of transformer
b) Obtain the approximate equivalent circuit of a given 200/2000 V single phase 30kVA transformer having the following test results.
O.C test: 200 V, 6.2 A. 360 W on Lv side
S.C. test: 75 V, 18 A, 600 W on hv side. [8+8]

4.a) Derive the condition for maximum efficiency of a single phase transformer.
b) A 20 kVA, 2200/220 V, 50 Hz transformer is tested for efficiency and regulation as follows:
O.C. test: 220 V, 4.2 A, 148 W (LV side)
S.C test: 86 V, 10.5 a, 360 W (HV side)
i. Efficiency at full load and 0.8 pf lag and
ii. Regulation at ¾ full loads 0.8 pf lead. [16]

5.a) Derive the expression for develop torque in a 3 phase induction motor and find the condition for maximum torque.
b) The starting and maximum torques of a 3 phase induction motor is 1.5 times and 2.5 times its full load torque. Determine the percentage change in rotor circuit resistance to obtain a full load slip of 0.03. Neglect stator impedance

6. a) Derive EMF equation of Alternator.
b) A 3- phase, 2.5 MVA, 6.6 KV synchronous generator gave the following data for open circuit test at synchronous speed.
If (A) 16 20 25 32 45
Voc (line) V 4400 5500 6600 7700 8800
with armature short circuited and full load current flowing the field current is 18A. Find the field current and voltage regulation when the machine is supplying full load current at 0.8 P.F log by at rated voltage. Neglect armature resistance use M.M.F method. [8+8]

7. a) Explain the methods of starting and principle of operation of single phase induction motor?
b) Explain the operation of a shaded pole type motor. [8+8]

8. With neat sketch explain the Basic principle of Moving iron instrument



Post a Comment

Get Syllabus in your Mail


Accenture Admission Notice - 2010 Admission Notification Anna University Anna University Chennai Anna University Question Papers Anna University Trichy Apparel Technology and Management Aptitude Questions Arts and Science Colleges Biomedical Engineering C and CPP Ebooks Calicut University CBSE Question papers Civil Engineering Civil Service Exams Colleges in India Colleges Result Computer Science Engineering Core Jobs CS R2008 CSE CSIR NET EBooks Download ECE EEE EIE Electives Electrical and Electronics Engineering Electronics and communication Electronics and Instrumentation Engineering Engineering Engineering Colleges in Maharashtra Engineering Colleges in TamilNadu Engineering Admissions Engineering Colleges Engineering Colleges in Karnataka Engineering Jobs Engineering Syllabus Entrance Exam Dates Entrance Exam Results Entrance Examination Exam Time Table Experiencer First Year Syllabus Freshers Full Time Jobs Government jobs in india Hardware and Networking Jobs Hotel Management and Catering Technology IGNOU Information Technology INTEVIEW QUESTIONS IT Jobs JNTU Question Papers Jobs in Bangalore Jobs in Chennai Jobs in Coimbatore Jobs in Delhi Jobs in Hyderabad Jobs in India Jobs in Kerala Jobs in Noida Jobs in Tamilnadu Jobs in TATA Karnataka Educations Lab Manuals Mechanical Engineering Medical Colleges Placement Papers Plus 2 Preparation for exams Private Jobs in India Question Papers Question Papers Download Results Announcement Semester 1 Semester 2 Semester 3 Semester 4 Semester 5 Semester 6 Semester 7 Semester 8 Syllabus Syllabus Download Tamil Movie TCS Placement Papers Teaching Jobs TECH MAHINDRA Textile Technology Top colleges University Results UPSC VICEVESVARAYA TECHNOLOGICAL UNIVERSITY waec Walk-in Interview Web Designers



Anna university Engineering Syllabus

Earn Money From Online

Government jobs in india

Admission Notification

Total Pageviews


Privacy Policy use third-party advertising companies to serve ads when you visit our website. These companies may use information (not including your name, address, email address, or telephone number) about your visits to this and other websites in order to provide advertisements about goods and services of interest to you. If you would like more information about this practice and to know your choices about not having this information used by these companies, click here.