Industrial Electronics - May 2013

Mechanical Engineering (Semester 4)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks. 1 (a) Draw VI characteristics of SCR with and without gate control and mark holding current and latching current? Explain the difference between holding current and latching current?(4 marks) 1 (b) Explain why cyclo converters are suitable only for low frequency applications?(4 marks) 1 (c) Explain the meaning of following instructions
(i) LDA address.
(ii) MVI M, 12H.(4 marks) 1 (d) Realize Ex-OR gate by NAND gate.(4 marks) 1 (e) Why RC triggering is preferred over resistance triggering process?(4 marks) 2 (a) Explain single phase full wave fully controlled bridge rectifier with the help of circuit diagram and waveforms.(10 marks) 2 (b) Explain the UJT relaxation circuit to trigger SCR along with appropriate waveform.(10 marks) 3 (a) Explain with block diagram the armature control method of speed control of a DC shunt motor.(10 marks) 3 (b) What is the difference between Natural and Forced commutation? Explain any two forced commutation techniques of SCR with waveforms.(10 marks) 4 (a) Explain any two circuits using SCR for the speed control of single phase induction motor.(10 marks) 4 (b) Draw the circuit diagram and explain the working of Jones chopper.(10 marks) 5 (a) Discuss the thyristerised overload and over voltage protection of DC motor.(10 marks) 5 (b) Explain important characteristics of OPAMP.(5 marks) 5 (c) Draw a neat schematic diagram for OPAMP in inverting and non-inverting mode?(5 marks) 6 (a) Which gates are called as universal gates? Why?
Using K-map reduce following Boolean function and implement it using NAND gate.
f(A,B,C)=Σm(0,1,3,4,5,6)(10 marks) 6 (b) Explain the various interrupts of 8085.(5 marks) 6 (c) Explain DeMorgan's theorem.(5 marks) 7 (a) Explain architecture of 8085 microprocessor with block diagram.(10 marks) 7 (b) Explain 555 timer as astable multivibrator.(10 marks)