PROCESS ENGINEERING
SECTION-I
Q1. (a) A mercury bulb thermometer showing a steady state temperature of 25°C is suddenly immersed into a hot bath at 120°C. If the time constant of thermometer is 8 sec. find:
I. Thermometer reading after 8 sec
II. Time required to read 90°C on thermometer
III. III. Time required for 75% response.
(b) Discuss the incentives for chemical process control
Q2. (a) Discuss the characteristics of underdamped response and plot the graph of overshoot and decay versus damping factor ξ
(b) Derive the transfer function of two tank interacting system.
Q3. (a) Define P, I and D controller and derive their transfer function. Discuss their open loop and closed loop response with diagram.
(b) Consider a second order system with following transfer function.
Gs = (s)/(s) = 1/s2 + s + 1 Introduce a step change of magnitude 1 into the system and find
i. Percent overshoot
ii. Decay ration
iii. Ultimate value of Y (t)
iv. Rise time
Q4. (a) Sketch the root locus for the following transfer function
Gs = k/s2(s2 + 2s + 2)
(b) Using Routh-Hurwitz criteria. Check the stability of system described by following equation.
s3 + 6s2 + 11s + 6 = 0
Q5. Define controller turning and discuss the following turning methods.
1) Cohen Coon technique
2) Time Integral performance criteria
3) One-quarter decay ration
SECTION - II
Q6. (a) Sketch the Bode plot
Gs = 1/ 2s + 1 (5s + 1)
(b) Derive the response of general First order system to Sinusoidal input. Define amplitude and phase lag.
Q7. (a) Explain Gain Margin and Phase margin with a neat sketch
(b) Sketch the Bode Plot for PI controller
(c) Sketch the Nyquist Plot for PD controller
Q8. (a) Explain Ratio Control with a neat sketch.
(b) Explain with a neat sketch Inverse Response system
Q9. (a) Explain the control instrumentation of cascade control for a jacketed CSTR
(b) Draw a neat sketch and explain
1) Feed-back control action
2) Feed-forward control action.
Q10. (a) Explain the reconstruction of continuous time signals from discrete time signal by using hold element.
Q11. (a) Explain in detail the role of digital computer in process control.
(b) What is Plant Wide control? Explain with a suitable example.
DIGITAL ELECTRONICS
SECTION 1
Q1. What is the effect of a derivative controller on peak overshoot of a second order undamped system?
Q2. List the advantages of PID controller.
Q3. What is aliasing?
Q4. State the effects of adding zeros to a system.
Q5. List any two properties of z-transform.
Q6. Define state variable.
Q7. Draw the basic structure of digital control system.
Q8. What is peak overshoot?
Q9. List some applications of digital control system.
Q10. What is data acquisition?
SECTION 2
Q11. (a) Discuss with block diagram PI, PD and PID controllers on transient response of a second order system.
(b)(i) Consider the system with G(s) = 10-4 /(s2 -1.21) and H(s) = 1. Design a proportional plus derivative controller Gc(s)=kp(I+kds) such that the damping ration is 0.7 and the undamped natural frequency is 0.5 rad/sec for the closed loop system.
(ii) Explain the need for controllers.
Q12. (a) (i) Describe the operation of zero-order and first-order hold with necessary expression.
(ii) Draw the diagram of sampler and Zero-order hold and drive the transfer function.
(b) (i) Explain the factors limiting the choice of sampling rate.
(ii) Define sampling theorem. Explain the frequency domain considerations in sampling and reconstruction.
Q13. (a) Obtaining the state variable model for the transfer function using first comparison and second Also draw the state diagram.
G(s) = (s+3)/(s3 +9s2 +24s+20)
(b) (i) Explain the procedure, necessary conditions and sufficient conditions for Jury's stability test.
(ii) Determine the pulse transfer function of linear discrete-time system in z-domain.
Q14. (a) The closed loop transfer function of a unity feedback digital control system is Y(z)/R(z) = (z+0.5)/3(z2 -z+0.5); T= 1 sec.
Find the open loop transfer function Gh0G(z). Construct the Bode the Bode diagram for GhoG(w) on w-plane. Determine gain margin, phase margin, resonant peak and bandwidth of the system.
(b) Write short notes on:
(i) Discrete integrator
(ii) Discrete differentiator
Q15. (a) With neat block diagram explain the interfacing of stepping motor drive circuits with microcontroller.
(b) (i) Derive the expression for PID control algorithm.
(ii) Explain the interface for temperature feedback with microprocessor.
MANAGEMENT OF ENERGY
Q1 (A) Describe the principles of energy management.
(B) Explain how energy can be saved in welding equipments.
Q2 (A) Explain different approaches of energy management.
(B) Methods of calculating deprecitions.
Q3 (A) Explain energy conservation by energy balance.
(B) Write a short note on energy storage.
Q4 (A) Explain how energy conservation can be achieved by energy balance
(B) Explain the term conservation of energy.
Q5 (A) How energy can be energy co-ordinary?
(B) How employees can be useful to conserve energy?
Q6 (A) Explain energy conservation in different sectors/ areas.
(B) Methods of calculating depreciations.
MEASUREMENT ENGINEERING
Q1. (A) The inductance of moving iron ammeter in micro henry is given by expression:
L=20+5θ-2θ2
Where θ is deflection in radians from the zero position. Determine the angular in radians for a current of 10A if the for a current of 5A is 300.Also determine the spring constant.
(B) Derive the general torque equation for a MI instruments?
Q2. (A) Explain the wattmeter errors in brief?
(B) For a certain electrodynamometer ammeter the mutual inductance M varies with the deflection of θ as M=-6cos(θ+300)Mh. Find the deflecting torque produced by the direct current of 50mA corresponding to the deflection of 600.
Q3. (A) A 220V,10A dc energy meter is tested at its marked ratings. The resistance of pressure coil is 9900ohm and that of current coil is 0.5ohm.Calculate the power consumed when testing the meter with
(i) Direct loading arrangements
(ii) Phantom loading with current circuit excited by a 6V battery
(B). Draw the Maxwell's bridge and give the balance equation.
Q4. Power in a dc circuit is calculated as the product of current and voltage if the value of current and voltage are given by 6.3A and 110.2V and the uncertainities involved in their measurement being 0.06A and 0.1V.Calculate the power dissipated by the loads and the uncertainity involved in measurement.
Q5. (A). Explain the measurement of pressure using transducer.
(B).Explain the method use to measure high resistance.
MICROCONTROLLER & MICROPROCESSORS
SECTION 1
Q1. Draw the diagram for organization of typical microcomputer system.
Q2. What are the advantages of microcontroller over microprocessor?
Q3. Classify the instruction set of 8085 microprocessor, and explain any one of them with example.
Q4. Write an assembly program to multiply a number by 8 using the rotate instruction
Q5. What are the ports available in 8255? What is the advantage of the third port?
Q6. What are the segments are available in 8086? Mention the use of each segments?
Q7. What are the devices required to interface 7 segment display with 8085? Mention the need of the devices used to interface?
Q8. Briefly explain the term "Co-processor".
SECTION 2
Q9. (a) (i) With a neat diagram explain the pin configuration of 8085 processor.
(ii) Mention the general specifications of a microprocessor.
(b) (i) What is the need of interfacing memory with a microprocessor? Explain the interfacing of memory mapped I/O in detail.
(ii) Write an assembly language program in 8085 with a subroutine to add two 16 bit numbers.
Q10. (a) (i) Draw the timing diagram of any one three byte instruction and explain the same in details
(ii) What is called as immediate addressing modes? Give examples.
(b) Draw the functional block diagram of 8279 an explain how the same is useful to interface and control its corresponding I/O devices.
Q11. (a) (i) Write an assembly language program in 8086 to add N one byte binary numbers stored from location X + 1 where N is stored at location X, store the result in location Y and Y+1.
(ii) Classify and explain the addressing modes of 8086.
(b) (i) Briefly explain the interrupts and its handling methods in 8086.
(ii) How much is the maximum memory can be interfaced with 8086?
Q12. (a) (i) Compare the Motorola 68000 with Intel 8085 microprocessor and mention the application of 68000.
(ii) What are the advantages of using microprocessor in a washing machine?
(b) Write an algorithm and assembly language program in 8086 to implement the digital clock.
Section 3
Explain with the hardware and software details required for interfacing and control the speed and direction of a steeper motor.