Industrial Electronics - Dec 2012

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.

Solve any five of the following:-

1 (a) Once SCR is triggered, the gate loses its control. Why?(4 marks) 1 (b) Explain why cyclo converters are suitable only for low frequency only?(4 marks) 1 (c) Why open loop configuration of OPAMP is not used for linear applications?(4 marks) 1 (d) Design a circuit using basic gates to implement the following Boolean equation.
Y = AB + A'B(4 marks) 1 (e) Write a program for loading a number 29H in register C and then displaying the same number in output port 01.(4 marks) 1 (f) Why RC triggering is preferred over resistance triggering process?(4 marks) 2 (a) Explain single phase full wave half controlled bridge rectifier (asymmetric configuration) with the help of circuit diagram and waveforms. Also explain why a separate FWD is not required in this case.(10 marks) 2 (b) Explain the regenerative action of SCR with the help of two transistor analogy.(10 marks) 3 (a) Explain the working of Modified Series Inverter with the circuit (which has two capacitors and two inductors) and waveforms. Also explain its advantage over simple series inverter.(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) Explain the block diagram of armature control method of speed control of DC shunt motor.(10 marks) 5 (a) Discuss the overload and over voltage protection of DC motor using SCR.(10 marks) 5 (b) Explain comparator circuit using OPAMP.(5 marks) 5 (c) Draw a neat circuit diagram of differentiator using OPAMP and derive the input output voltage relation.(5 marks) 6 (a) Realize Ex-or gate by
(i) Basic gates.
(ii) NAND gate.(10 marks) 6 (b) Which gates are called as universal gates? Why?(5 marks) 6 (c) Explain Demorgan's theorem.(5 marks) 7 (a) Explain the architecture of 8085 Microprocessor with block diagram.(10 marks) 7 (b) Explain 555 timer as monostable multivibrator.(10 marks)