Prof.

Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
MODULE- 1 [PART-B]
Short answer type questions ( Each question carries 5 mark):
1. Define the terms Industry, Automation and control? Describe the need of Automation in industry. 3+2
2. What are the functional elements of Industrial Automation system? Briefly describe with schematic diagrams. 5
3. What are the different types of control used in industry? Briefly describe with schematic diagrams. 5
4. What is automation pyramid? Describe the Automation pyramid with schematic diagram. 1+4
5. What are the different variables associated with regulatory continuous process control loop? Describe with an example. 5
6. Describe the functional elements of a measurement system or instrument with schematic. 5
7. What is accuracy and precision of a measuring instrument. What are the difference between them? Explain with an
example. 2+1+2
8. Describe the frequency response performance characteristics of a dynamic system. What does it mean by random
characteristics of an instrument? 3+2
9. What is inverse transducer? Give example. Explain the advantages of Electrical transducers. Describe the conditions to be
considered in selecting a transducer for a specific measurement. 1+2+2
10. What is resolver? Explain the principle of operation of resolver with schematic diagram.
11. What is the basic difference between LVDT and RVDT? Explain the operation of RVDT with schematic diagram. What
are the applications of RVDT? 1+3+1
12. Describe the operation of fiber optic displacement sensor with schematic diagram. 5
13. Explain the operation of non-metallic diaphragm pressure gauge with schematic diagram. What are the advantages and
disadvantages of diaphragm pressure gauge? 3+2
14. Explain the different elastic type pressure sensors used in industry.
15. Explain the operation of proving Ring as a force sensor with schematic diagram. 5
16. Explain the operation of cantilever. Beam as a force sensor with schematic diagram. 5
17. How ultrasonic sensors works? Explain the operating principle and configuration of a ultrasonic sensor. Mention the
application of ultrasonic sensor.
18. What are the roles of signal conditioning circuits in a measurement system? Explain briefly with relevant schematic
diagram. 5
19. Explain the capacitance amplifier circuit act as half bridge and determine the output voltage of the amplifier. 5
20. a) Name five kinds of transducers in respect of energy conversion for the force measurement.
b) Draw a free hand sketch of the scheme for any one of the same. 3+2
21. A resistance wire strain gauge with a gauge factor of 2 is bonded to a steel structure subjected to a stress of 100MN/m 2.
The modulus of elasticity of that structure is 200GN/ m 2. Calculate the percentage change in the value of the gauge
resistance due to the applied stress.
22. How can strain developed on a strain gauge be measured by using full-bridge configuration? Derive the sensitivity
relation between quarter bridge, half-bridge & full-bridge configurations. 2+3
23. What is piezo-resistive effect? Why the linearity & sensitivity of a POT are conflicting to each other? 2+3
24. a) What are bimorphs?
b) A quartz crystal having a thickness of 2mm. and voltage sensitivity of 0.055v-m/N is subjected to
a pressure of 1.5MN/ m2.Calculate the output voltage. If the permittivity of quartz is 40.6 x 10 -12 F/m. Calculate the
charge sensitivity. 2+3
25. When is non linearity introduced in the performance of a resistance potentiometer? Comment on the
linearity & sensitivity of this transducer. 2+3
26. What is a piezoelectric transducer ? Give its equivalent ckts. Derive an expression for the output
voltage by making suitable assumptions. 1+1+2
27. Discuss the use of platinum in metal resistance thermometric sensor. 5
21. Compare digital transducer with analog? What are the suitable materials for piezoelectric transducer? 3+2

Long answer type questions ( Each question carries 15 mark):

1. What are the types of Industrial automation used in manufacturing processes? Briefly describe the overview of these
Automation techniques. 3+12
2. a) What is called static characteristics of a measurement system. Define the major static characteristics parameters of
measurement system.
b)What is dynamic characteristics of a measuring instrument? Explain with an example. 2+6+7
3. a) What is transducer? What are the fundamental elements exist in a transducer? Describe the operation of transducer with
schematic diagram. What are the basic requirements of transducers?
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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
b) How can we classify the transducers? Describe this classification with example of different transducers. 2+2+3+2+6
4. Explain the operation of potentiometer as a Displacement transducer. Determine the characteristic and error curve due to
loading effect in potentiometer. What is the sensitivity of the potentiometer? 5+7+3
5. Derive the expression for error of a resistance potentiometer when connected across a load of finite resistance. Draw typical
curves to show the variation of errors with input displacement for different values of load resistance. 9+6
6. Explain the operation and output characteristic of LVDT as an inductive transducer. What are the advantages and
disadvantages of LVDT? Identify some applications of LVDT. 6+4+5
7. Describe the principle of operation of capacitive transducer as a linear and angular displacement measurement. Explain the
characteristics and sensitivity of the transducer using change in area of different types of capacitor. 7+8
8. a) Describe the operation, characteristic and sensitivity of capacitive transducer using change in distance between plates.
b) Explain advantages, disadvantages and applications of capacitive transducer. 8+7
9. Explain the operation and characteristic of capacitive transducer for displacement measurement using change in dielectric
content between plates. Determine the sensitivity of the differential arrangement of that capacitive transducer. 8+7
10. a) What are the different types of diaphragm used in pressure measurement? Explain the operation of metallic diaphragm
with schematic diagram.
b) Explain the operation of bellows type pressure sensor with schematic. What are the advantages and disadvantages of
Bellows element? 2+4+5+4
11. Explain the operation of C-type Bourdon tube with schematic diagram. What are the types of adjustment and material used
in Bourdon tube? What are the advantages and disadvantages of Bourdon tube used in industry? 7+4+4
12. a)What is strain gauge? What are the types of strain gauge? Describe the working principle of strain gauge and determine
the relation between gauge factor (G) and Poisson’s ratio.
b) What are the circuits used to measure the resistance of strain gauge? Explain the operation of most efficient measuring
circuit. 1+2+5+2+5
13. a) What are the different Wheatstone bridge measuring circuits are used in stain gauge? Explain the operation of most
sensitive bridge circuit and determine its output sensitivity.
b) What are the different types of stain gauges according to design? Describe the construction of most common types of
stain gauges with schematic diagram. 2+5+3+5
14. a) Describe the characteristic of strain gauge for satisfactory operation. What are the advantages and applications of strain
gauges?
b) What is load cell? What are the common types of load cell? Describe the construction and working principle of strain
gauge type load cell? 3+4+2+6
15. a) What are different commonly used temperature transducers used in industry. Compare those transducers with their
temperature operating range. 5
b) What is cold junction compensation in thermocouple? Describe the techniques used for this compensation? 2+8
16. Discuss the working principle construction and characteristic of industrial RTD. Depending upon the material what are the
different types of RTD? Describe their characteristics and operating range. What are the advantages and disadvantages of
RTD? 5+4+6=15
17. What are the different lead wire compensation techniques used in RTD? Explain the operation of that compensation
techniques. What are the advantages of this technique? 2+10+3=15
18. a) What is the operating range of thermistor? What are the different types of thermistor? Discuss the principle of operation
and characteristics of thermistor. Compare the characteristic of thermistor with RTD. 1+1+4+2
b)What is the principle of operation of the thermocouple? Discuss about different types and characteristics of thermocouple.
What are the advantages and disadvantages of thermocouple? 2+3+2
19. What are multiple thermocouple configurations used in industry? Describe these configurations with relevant diagram.
What are the utilities of these configurations? 4+8+3
20. a) What is meant by gauge factor? Derive the expression.
b) What is dummy gauge?
c) A strain gauge having nominal resistance of 350 Ω is subjected to strain of 500microstrain. Find
the change in the value of resistance neglecting piezoresistive effect.
d) What are the advantages of semiconductor strain gauge over metallic strain gauge. 2+4+2+5+2
21. a) Explain how the magnitude and direction of the displacement of core of a LVDT can be detected. What are the reasons
behind the residual voltage of LVDT?
b) Draw the schematic diagram of LVDT and explain its electro-mechanical transfer characteristics. 5+3+3+4
22. a)How can angular displacement be measured with the help of a wire wound resistive POT? Draw the characteristic curve.
Find the expression for sensitivity. How can resolution be increased?
b) A linear resistance POT is 10 cm. long and is uniformly wound with a wire of total resistance of 10KΩ. Under normal
condition the slider is at the centre of the POT. Determine the linear displacement when the resistance of the
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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
potentiometer as measured by a Wheatstone bridge is 3900 Ω. 5+2+2+1+5
23. a) What are the different materials used in resistance potentiometer wire?
b) How is strain gauge affected by temp. change? In case of a load cell, derive the output voltage in terms of applied load.
4+5+6
24. a)Derive the expression of output of the resistance potentiometer when connected to a meter.
b)Total resistance of the POT is 20 KΩ and the length of the potentiometer resistance is 8mm. The power rating is 40mW.
Determine the output voltage when the displacement of the wiper is 2.4 mm. assuming the maximum permissible excitation
voltage. Also calculate the accuracy at 50% full scale travel of the wiper with a meter having a resistance twice the resistance
of the POT.
c) What is dummy gauge? How can strain developed on a strain gauge be measured by using Full bridge configuration?
Derive the sensitivity relation between quarter bridge, half-bridge and full- bridge configuration of strain gauge measurement.
5+5+1+1+3
25. a) How the capacitive transducer can be used to measure the level of non-conducting liquid? What special arrangement
should be done while measuring conducting fluid.
b) Explain the Wheatstone bridge method and find the output voltage in strain gauge. 5+5+5
26. Derive the expression for impulse response of piezoelectric transducer and sketch the response curve. What are bimorph
and multimorph? Give some examples of natural and synthetic PZT materials. 7+6+2
27. State the basic principle of capacitive transducer. How the capacitance changes with overlapping area, distance between
the parallel plates and the dielectric medium. Also find out the respective sensitivities. Draw the respective curves. Mention
the ranges of measurement. 2+9+4
28. Short notes: (Each question carries 5 marks)
➢ bonded type strain gauges,
➢ unbounded type strain gauges,
➢ foil type strain gauges,
➢ semiconductor type strain gauges,
29. a) What is thermoelectric effect and electrothermic effect? On which principle amongst these two a thermocouple can
work? Mention the name, composition and operating range of five commonly used thermocouples.
b) What is CJC? Why is this necessary? Explain the software technique of CJC. 4+1+5+1+1+3
30. Describe the working and construction of resistance thermometer. Describe the materials used for RTDs along with their
properties. Sketch their typical characteristics. 5+7+3
31. Draw the characteristic of different RTDs. Explain 2-wire, 3-wire and 4-aire RTD. 3+12
32. Explain the working principle of pneumatic and piezoelectric type load cell. 8+7
33. State the basic principle of capacitive transducer. How the capacitance changes with overlapping area, distance between
the parallel plates and the dielectric medium. Also find out the respective sensitivities. Draw the respective curves.
Mention the ranges of measurement. 2+9+3+1
34. Explain the working principle of pneumatic load cell with proper diagram. Also deduce the transfer function. 8+7
35. What are the disadvantages of capacitive transducers? With circuit diagram explain how to linear the
capacitive transducer. How parallel capacitor works? 3+8+4
36. What is unbalanced D.C Wheatstone Bridge? Explain operation, characteristics and sensitivity of unbalanced D.C bridge
with one arm act as resistive sensing element. 2+12
37. What is push pull configuration of unbalanced D.C bridge. Discuss the operation and output of a resistive push pull
unbalanced D.C bridge. What is the advantages of this bridge configuration?
38. Discuss the unbalanced A.C bridge with push pull configuration for inductive sensors and capacitive sensors. Derive the
input output relation of this bridge. What is the difference between inductive sensor bridge and capacitive sensor bridge?
What is the purpose of phase sensitive device in inductive and capacitive sensors? 5+5+2+3=15
39. What is calibration of an instrument. Describe briefly the different calibration techniques of measuring instruments. 2+8
40. Describe the limiting error of an instrument with example. Discuss the least square curve fitting technique for n no of
observed data in a straight line expressed as y = a0 + a1 x . 5+10
41. a)Prove that the most probable value of a set of dispersed data is the arithmetic mean. Consider n no of observed data
x1 , x2 ,......xn and control value is X. 5
b) Define the terms mean value, deviation, mean of deviation and variance. State the relation between variance (V ) and
standard deviation (T ) . 10
42. What is the purpose of data conversion device in sensor signal conditioning circuits? Briefly describe the common data
conversion devices. 3+12=15

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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
43. a) What are the different sensor protection circuits used for high current and high voltage protection? Explain briefly the
operation of that protection circuits. 4+5
b) What are the advantages of instrumentation amplifier used in signal conditioning circuits? Determine the input-output
relation of the given instrumentation amplifier. 6

MODULE- 2 [PART-B]
Short answer type questions ( Each question carries 5 mark):

1. Explain the difference between open and closed- loop control. 5

2. What is Reset action? Prove that P.B = 100/Kc , where symbols have their usual meaning. 1+4
3. Where an on-off controller is recommended? How its performance is affected by the process dead time? 5
4. Derive the expression of “P” controller and determine its parameter. 5
5. Derive transfer function of P, PI, PD, PID control action and show the controller output curve with standard error
input. 5
6. Discuss with reasoning, how “P” controller is used as a On-Off controller? 5
7. Explain graphically what will be the controller output if we adopt “ P” control , “I” control and “PI” control
independently. 5+5
8. Define reverse and direct actions of a controller. In what way single speed floating control is different from ON-OFF
control. 3+2
9. Describe with schematic diagram the relation between proportional band ( PB ) , proportional gain ( K p ) , controller
output and offset of P controller. What are the applications of P controller? 3+2
10. a)Why “I” control is known as “Reset” control?
b) Why derivative control is known as anticipatory control? 3+2
11. Error curve rises linearly to 1% in 0.5 min and remains fixed at 1% . K P =2 , Kd =Td = 1 min, Ki = Ti = 0.5/min.
Steady sate value of controller at zero deviation is 0%. Find the controller output at t= 0, 0.5 min. , 1min when the
controller is i) PD ii)PI 5+5

12. a) Find the transfer function a PID controller which has proportional band of 75, reset time of 5 seconds and rate of 7
seconds. 3
b) What do you mean by Rate time and Reset rate of a PID controller? 2
13. For a single speed floating control, a process error lies within the neutral zone with controller output (m) = 20%. At t =
0, the error falls below the neutral zone. If the rate constant K f = ± 3% per second, find the time when output
saturates. 5
14. What is the controller output for a PD controller initially and 2 sec after the error begins to change from zero error at
the rate of 1.2%/S ? The controller has a set point of 50%, K P =4 and KD = 0.4%s/%. 5
15. An Integral controller is used for level control with a set point of 11 m within the range of 10 to 16 m. Controller
output is 20% at set point. The constant KI is 0.16% per second per percent error. If the level jumps to 14 m. calculate
the controller output after 3 seconds. 5
16. A PI controller is used to control the pressure in a tank which varies from 30 psi to 130 psi. Desired pressure is 95 psi.
Controller output is to change by 100% upon 30 psi pressure deviation. Reset rate is ¼ repeats per minutes and
controller output at zero error is 40%. Calculate the controller output at the end of 2 minutes, when pressure of the
tank becomes 85 psi. 5
17. What will be the controller output of a PID controller having K P as 4%/% , KD as 0.5%s/% , KI as 0.6%/%s , a set
point output of 50% and subject to the error change in fig. Below, -
(a) immediately the change starts to occur and (b)2 sec after it starts? 5

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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
18. What is proportional band? Explain the working principle of time-proportional control. How is time proportional
control different from ON-OFF control? 1+3+1
19. what is meant by tuning of controller? What are the basic criteria of tuning of controller? What are the different
methods of tuning of controllers? 1+3+1
20. Define the pneumatic controller . How pneumatic controller can be designed. Compare between different pneumatic
controller design technique. 1 + 1+ 3
21. Design an electronic “P” controller and calculate the proportional gain. 5
22. Design an electronic integral controller and calculate T i as parameter of Integral controller. 5
23. An integral controller with a value of KI of 0.10%/%S has an output 40% at the set point , what will be the controller
output after (a) 1 sec ; (b) 2 sec; if there is a sudden change to a constant error of 20%? [Calculate the controller o/p in
terms of mA ]. 5
24. Design an electronic “D” controller and calculate the gain. 5
25. A derivative controller has a set point of 50% and derivative constant K D of 0.4%S/% . What will be the controller
output when the error (i) change at 1%/Sec and (ii) is constant at 4%. 5
26. Explain an Electronic ON-OFF controller with differential gap using OPAMP as Schmitt trigger circuit and define the
on and off condition. 5
27. Implement an electronic PI controller using operational amplifier, having proportional gain of 4.7 and reset time of 3
sec. 5
28. What is reset rate? What is integral wind up ? What are the applications of PI control action? 5
29. Why D control action is called anticipatory control action? Discuss about the PD controller output for different
standard inputs? 5
30. Discuss the output response of PID controller for standard error inputs. 5
31. Describe the electronic P-controller and determine the controller gain? 5
32. Describe the electronic PI-controller and determine the controller gain? 5
33. Describe the electronic PD-controller and determine the controller gain? 5
34. Describe the electronic PID-controller and determine the controller gain? 5
35. Describe the electronic D-controller and determine the controller gain? 5
36. Describe the electronic I-controller and determine the controller gain? 5

Long answer type questions ( Each question carries 15 mark):

1. (a) Explain the major problem of proportional(P) controller when set point is changed?
(b) Discuss analytically the problem of proportional controller in a first-order process.
(c) Explain how the problem can be eliminated using proportional integral (PI) Controller. 4+7+4
2. What is integral control action? How can you define integral gain? Describe the characteristics and output of integral
controller with a step input? Explain why integral control can not be used alone? 10+5
3. What is derivative control action? How you can define the derivative gain? Why derivative controller cannot be used
alone? Show the derivative controller output for different rate of error input? Discuss about the characteristics of D
control mode? Compare the benefits and drawbacks of P, I and D control modes? 2+2+2+4+5
4. What are different composite modes of control action? Discuss about the PI controller output for different standard
inputs? What are the characteristics of PI control actions? 3+6+6
5. a) Describe the integral windup with an example. What are the prevention techniques of integration windup?
b) What is the Bump less transfer of PID controller? How it is implemented? 5+5+5
6. What are the Fundamental components used in a pneumatic controller? Describe the operation of that’s units. 2+8=10
7. What is controller tuning? What are the basic criteria of controller tuning? What are the different techniques of
controller tuning? 2+4+4=10
8. Describe the Ziegler-Nichols close loop PID controller tuning techniques. What are the major drawbacks of this
technique? 10+5
9. What is process reaction curve method of controller tuning? What are the parameters required to be determined from
PRC used in controller tuning equations? Discuss the procedure of Cohen Coon open loop controller tuning technique.
2+5+8=15
10. (a) Draw the block diagram of a feedback control loop. Assuming the transfer functions of the final control element
and the measurement device to be unity, Show that for a first order process under P-action, a change in load leads to
offset. Also prove that introduction of integral action eliminates this
offset.

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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
(b) Explain the effects of PI, PD, and PID control actions on the process response. Explain why I, D
actions alone cannot improve the plant response. 3 +6+ 6
11. Describe the liquid level control system using ON-OFF controller. What are the advantage, disadvantage and
applications of ON-OFF controller? 8+7=15
12. Discuss the different functional blocks of a closed loop control system with examples. 15
13. Write mathematical equation for a PID action. Derive the transfer function of such a control action. Give a comparative
study of P, I, PI , PD, PID actions in details with necessary graphical representations. 4+4+7
14. Explain Integral rate and Derivative rate of controller ? Find an expression for the
transfer function of PID controller. What will be transfer function of a PI controller when it has a proportional band
(P.B) of 50% and Integral time of 2 seconds? 5 +3+4
15. (a) Describe the flapper nozzle system for transduction between pressure and mechanical motion.
(b) Describe I/P converter using flapper nozzle system . 8 +7
16. (a) Mention different tuning parameters of PID controller.
(b) Describe Ziegler- Nichols closed-loop tuning techniques to tune the PID controller.
(c) What are the advantages and disadvantages of this method? 2 + 8+5
17. (a) Write down the equation of a PID controller and explain the terms used.
(b) Implement an electronic P+I controller using operational amplifiers, having proportional gain of 9.4 and
reset time of 6 seconds.
(c) Differentiate between the principles of operation and application areas of a proportional controller and
an ON-OFF controller. Define proportional band and Show that On-OFF control can be considered as a
narrow proportional band controller using electronic circuit. 4+6+5
18. (a) Discuss pneumatic P-I and P-D controller with a schematic.
(b) Explain an Electronic PD controller and derived its control equation from its circuit diagram. 10+5
19. (a) Discuss pneumatic PID controller with a schematic.
(b) Explain an Electronic P-I controller and derived its control equation from its circuit diagram. 7+8
20. Why controller tuning is required? Explain the different controller tuning techniques (Open and close loop
Tuning technique). 3 + 12
21. Mention different tuning parameters of PID controller. Describe Ziegler-Nichols closed-loop tuning
technique to tune the PID controller. What are the advantages and disadvantages of this method. 3 +7+5
22. a) Explain the PRC method of controller tuning developed by Cohen and Coon. What are the required parameters from
PRC used for controller tuning? Write the Cohen and Coon tuning equation. 4+3+3
b) In Ziegler-Nichols controller tuning method, the Ultimate gain (Ku) was found to be 4.2, and Ultimate
period (Pu) of oscillation was 2.21 min. What will be standard setting for PID control. 5
23. a) How digital PID controller is implemented? Describe the common algorithms used to implement digital
PID controller. 5+6
b) Derive the difference equation of u(k) in terms of y(k) and r(k) for PID controller using backward rectangular rule.
Reference input is constant. 4
MODULE- 3 [PART-B]
Short answer type questions ( Each question carries 5 mark):

1. What is ratio control, and why it is useful in process control? Give three specific examples. 5
2. How do you select the desired value of the ratio in a ratio control system? Explain with example. 5
3. Why cascade control gives better response than simple feedback system? Explain 5
4. What types of controllers would you use for two controllers of a cascade control system? 5
5. Discuss the different measured and manipulated variables in different drum level control in a boiler
[1,2,3 element drum level control]. 5

Long answer type questions ( Each question carries 15 mark):

1. Discuss ratio control system with different configurations. Configure a ratio

Control with cascade control and show that the ratio of two variables is constant. Take the
controller as P controller. 8 +7
2. (a) Explain with a neat sketch how cascade control is implemented for temperature control of a heat
exchanger or CSTR and why it is more effective than simple feedback control.
(b) Why feed-forward control is referred to as anticipatory control? Explain
(c) An equal percentage valve has a maximum flow of 50m 3/hr and a minimum flow of 2m3/hr. if the
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 Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
full stem travel is 3 cm, find the flow through the valve for a stem travel of 1cm. what is the
rangeability of the valve? 5 +5 +5
3. Define ratio control system? Discuss such a control system with a specific process. Is it possible to adopt ratio on
control system for controlling the ratio between three elements. Justify your answer.
2+6+7
4. What is cascade control system? Draw the block diagram of such system. Explain this control scheme with a suitable
example. What are the constraints of this type of scheme? 2+5+6+3

MODULE- 4 [PART-B]
Short descriptive type question (Marks of each question is (5):

1. Why positioners are used with actuators? 5

2. Write short note on “ Pneumatic actuators” . 5
3. What are the different types of actuators? What are the functions of an actuator on a control valve. 2+3
4. Write short note on “ Stepper motor actuators” . 5
5. What is the role of CV in valve selection and sizing? 5
6. What do you mean by double seated valve? Why is it advantageous over single seated valve? 3+2
7. “Actuator power required for a single seated valve is greater than the double seated valve.”Justified the statement with
proper diagram. 3
8. Explain the operation of I-P converter? 5

Long answer type questions ( Each question carries 15 mark):

1. (a)A 1.5 inch control valve has the following specifications. At 30% valve opening , C v = 0.9 ; at 40%opening
C v = 1.5, and at 80 % valve opening, C v =9.25. calculate C v at 90% valve opening when the control valve has equal
percentage and linear valve characteristics.
(b) A heating furnace requires a control valve passing 10 gpm preheated light oil (S G =0.8) at full load and
only0.2 gpm at the smallest heating load. The pressure difference at wide open is 20 Psi. Calculate (i)Turn
Down (T) (ii) Rangeability (R ) (iii) CV and (iv) KV 5+2+2+2+2+2

2. (a) Describe the purpose of actuator in final control operation.

(b) Describe the principle operations of pneumatic and hydraulic actuators.
(c) Describe with block diagram of a servo loop.
(d) Alcohol is pumped through a pipe of 10 cm diameter at 2m/s flow velocity. Find the volume flow rate. 4+6+3+2
3. (a) Describe the flapper nozzle system for transduction between pressure and mechanical motion.
(b) Describe I/P converter using flapper nozzle system .
(c) Suppose a force of 400N must be applied to open a valve. Find out the diaphragm
area if the gauge pressure of 70KPa must provide this force. 5+5+5
4. (a) What is the necessity of control valve sizing? What are the factor that should be
known for selecting a valve?
(b) Water flow is controlled by 2 in. butterfly valve with a 4 psi differential. What is
the maximum flow rate? What will be the flow for glycerine (= 1.26gm/cc)?

Valve 0.25 0.50 1 1.5 2 3 4 6 8

size in
inches
Cv 0.3 3 14 35 55 108 174 400 725

(c) What is the necessity of a final control element in a process loop? How do you select it? 2+4+4+ 5

5. a)Discuss the different control valve characteristics with schematic of plug contour.
b)Why control valve sizing is required? Discuss the methodology of control valve sizing. 7+8
6. What are different types of actuators? Describe the working of a pneumatic spring actuator and label its
different parts. What are the forces that affect the performance of the pneumatic actuator? How the effect can
be minimized? 3+7+3+2
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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
7. a) Define Cv factor for valve sizing and draw the valve characteristics.
b) How is valve selection made?
c) Why cavitation occurs in a control valve ?
d) A 2.5 inch control valve has the following specifications
At 40% valve opening Cv = 0.8 ; at 50% valve opening Cv = 1, and at 70% valve Opening, Cv= 6.5 .
Calculate Cv at 80% valve opening when the control valve has Equal percent characteristics. 2+5+4+4

MODULE- 5,6 [PART-B]

Short answer type questions ( Each question carries 5 mark):

1. Describe the basic functional blocks of a PLC. 5

2. What is ‘TIME ON” delay ? Mention its done bit (DN), Timer enable (EN) bit and timer timing bit(TT) set condition
and remain set until condition in form of table. (1+4)
3. What is ‘TIME OFF” delay ? Mention its done bit (DN), Timer enable (EN) bit and timer timing bit(TT) set condition
and remain set until condition in form of table. (1+4)
4. Develop a ladder program with I/O detail and timing diagram for the following conditions.
Start push button switch starts motor 1, after 10 second motor 2 start. Stop switch stops motor 1,
after 15 second motor 2 stop. 5
5. Draw the ladder diagram with I/O detail and timing diagram where start switch starts motor 1 and 2 . stop switch stops
motor1 . After 15 second motor2 stops. 5
6. Describe the DDC structure with schematic? What are advantages and disadvantaged of DDC System.
7. What is meant by HART protocol? Describe the typical HART architecture with principal
technical Data of HART. (1+4)
8. Describe the PROFIBUS architecture with different features of PROFIBUS DP and PROFIBUS PA.
9. What are the different transmission mediums used for data Highway. Show the comparative study
according to relative features of different data Highway transmission medium. (1+4)
10. What is meant by data highway? Why is fiber optic more attractive for data highway design? (2+3)
11. Draw the block diagram of Fuzzy Logic control (FLC) system and briefly explain the functions of
different block elements.
12. Describe with schematic of current DCS topology with different I/O buses interfacing. (5)
13. Discuss with comparison about the different features of different field buses used in DCS system. (5)
14. Discuss about the different type of display commonly used is DCS. (5)
15. Describe the token passing procedure using in Token ring network with the help of flow chart. (5)
16. Describe the token ring priority scheme with example. (5)
17. Describe the operation of CSMA in network access. (5)
18. What is the difference persistence strategy for sensing busy medium a network. (5)
19. Describe the CSMA/CD procedure with the help of flow chart. (5)
20. Discuss the polling selecting process between a primary station and secondary station. (5)
21. Describe the token passing procedure with the help of flow chart. (5)
22. What is meant by HART protocol ? Describe the typical HART architecture with principle technical
data of HART. (5)

Long answer type questions ( Each question carries 15 mark):

1. What is the function of I/O module in a PLC? How many types of I/O modules are
available in PLC. Briefly describe any one type of input module and output module. 3+2+10
2. What are the different types of Timers in a PLC? What are the parameters of PLC timer? Describe in form of Table the
different status bits set condition and remain set until condition for different types of Timer in PLC. 2+3+10
3. a)Define PLC? What are the advantages of PLC in control system? How many types of PLC are available in market?
b) Develop a ladder to fulfill the following condition:-
Level switch (LS1) turns On when the level is greater than high level (L1) . Start
switch turns On the system. When level is below L1, pump is to be turned on. When level is
above L2, pump has to be switched off. 2+3+3+7

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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering

4. a) What are the different data files are available in PLC? Briefly describe the
function of each data file in PLC?
b) When the system is turned ON , motor is to alternate rotation clockwise(CW) and
then counter clockwise (CCW). Continuously as the shaft extension contacts the
two limit switches RLS(Right limit switch) and LLS(Left limit switch). Prepare
ladder diagram with I/O detail to provide the motion. 3+4+8

5. (a)Described the FOUNDATION field bus architecture with different features of Foundation field bus HI and Foundation
field bus HSE.
(b) Describe the Ethernet TCP/IP architecture of PROFIBUS DP as control network. Discuss the main features of the
network. 8+7=15
6. (a) Explain the ISO-OSI communication model in the context of the field bus user.
b) Explain the function of each layer with example of standards/Realizations for field bus. 8+7=15
7. (a) Describe with schematic of the different components of DCS system, showing its physical structure.
(b) Describe with schematic of the functional components of a DCS system. 5+5=10
8. (a) Discuss with schematic of CIP data communication hierarchy of a production industry.
(b) Discuss the serial transmission and parallel transmission along with PIA adaptor with
schematic diagram. 7+8=15
9. (a) Discuss the serial transmission and parallel transmission along with PIA adaptor with schematic diagram used in
process control application.
(b) What is the purpose of field bus in DCS network? Briefly describe about the different
field bus protocols used in DCS system. 7+2+6
10. What is Shared BUS or BUS topology used in DCS network ? Briefly describe this topology in the contest of DCS
network with schematic. What are the main advantages of this topology over other network topology. What are the
different communication relationship supported by Bus topology. 2+6 +2+5=15
11. What is CSMA/CD protocol? Why this protocol is preferred over other network access protocol in MULTIDROP type
DCS. Discusses with schematic. 2+8
12. What is STAR topology used in DCS network ? Briefly describe the topology in the contest of DCS network with
schematic? What are the drawbacks of this topology ? How drawbacks can be overcome. 2+4+2+2 [Estimated time :
6 min ]

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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
13. What is RING topology used in DCS network? Briefly describe this topology in the contest of DCS network with
schematic? What are the drawbacks of this topology ? How drawbacks can be overcome. 2+4+2+2

[PART-C]
MODULE- 1 [PART-C]
1. a) Explain the terms sensor and transducer? Name the components of a transducer? What is electrical pick up?
2+2+1 [Estimated time: 5mins]
b) State the different types of transducers? Give one example of each type. 5 [Estimated time: 5mins]
2. State the different types of errors incorporated in a sensor? Explain the same. Describe the different criteria for
selection of transducers for a particular application. 5+5 [Estimated time: 10mins]
3. Explain the terms accuracy, resolution and sensitivity. 6 [Estimated time: 5mins]
4. a) Define power? How it is related to the sensitivity and resolution of a potentiometer? Which one is more accurate
between carbon film and wire wound types? Why this is called potential divider? 1+2+1+1 [Estimated time: 5mins]
b) Define resistivity? How resistance is changed with the change in dimension for strain gauge?
What is young’s modulus and Poisson’s ratio? 1+1+3 [Estimated time: 5mins]
5. a) Is the voltage sensitivity dependent on gauge factor? 5 [Estimated time: 5mins]
b) How the sensitivity of a full bridge is maximum over others. Explain. 5 [Estimated time: 7mins]
6. Name different base and adhesive materials. State an industrial application of strain gauge. 3+2 [Estimated time:
8mins]
7. a) Explain the four terms of LVDT. What is the frequency range of input signal given to it?4+1[Estimated time:
5mins]
b) The material of the core of LVDT is laminated. Explain why. What is the name of the circuit connection in the
secondary? Why the residual voltage is not zero? 2+1+2 [Estimated time: 5mins]
8. a)Why the core of the LVDT is laminated? Why the core is made of high permeability material? If a dc voltage is
given to the primary of the LVDT what will happen? 1+1+2 [Estimated time: 5mins]
b) A 0-15A Ammeter has an accuracy of ±0.8%. What is its accuracy when measuring of
current 5A? 4 [Estimated time: 4mins]
9. a) A strain gauge bridge comprises of two fixed 120Ω resistors and one is an active gauge & one unstrained
temperature compensating gauge. The two gauges have an unstrained resistance value of 120Ω each. The gauge
factor is 2.2. Find the strain which would represent by 100KΩ calibration resistance shunting one arm of bridge. 5
[Estimated time: 8mins]
b) Two strain gauges attached to the surface of a cylindrical pressure vessel, one in axial and one in circumferential
direction gave the strain values of 0.00018 and 0.00072 respectively. Calculate the hoop and the longitudinal stress
values if the cylinder is of steel having a modulus of elasticity of 200GN/m 2 and Poisson’s ratio=0.29.
5 [Estimated time: 6mins]
10. a) How does the resistivity of a gauge material having Poisson’s ratio 0.4 and gauge factor 2 changes with strain? If
Young’s modulus of the material is 2x106kg/cm2. 3 [Estimated time: 3mins]
b) For a 100 turn POT, if once the 50 th wire is only contacted while at the next instant, 50th and
51st wires are shorted by the jockey, what would be the %loss in resolution in the second case if
the supply voltage is 10V? 6 [Estimated time: 5mins]
11. a) A unity ratio quarter bridge strain measuring circuit produces an output of 5 mV for a strain of 800microstrain
when the bridge excitation is 9V. Determine the gauge factor of the element.
5 [Estimated time: 4mins]
b) The output voltages of the two secondaries of a LVDT are 12V (rms) respectively for a
displacement of 24x10-4 cm. The output is measured by a 7V voltmeter which has a scale with
100 divisions. What will be the sensitivity. Also find out the resolution. 5
[Estimated time: 5mins]
12. A 350Ω No-Cr strain gauge with G=2 working at 2000microstrain. What is the output level for quarter bridge excited
at 20V? 4 [Estimated time: 3mins]
13. A strain gauge is bonded to a steel beam 0.1m long and has a cross-sectional area 4cm2. Young’s modulus for steel is
207GN/ m2. The strain gauge has an unstrained resistance of 240 Ω and a gauge factor of 2.2. When a load is applied,
the resistance of gauge changes by 0.013 Ω. Calculate the force applied to the beam. 5 [Estimated time: 7mins]

17
Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
14. If the air-gap between the teeth of the two electrodes of a serrated type capacitive transducer is 0.1cm and the active
tooth length is 1cm. What is the sensitivity factor of the sensor? Assume constant term as 4. 5
[Estimated time: 5mins]
15. a) If the diaphragm diameter is 2.8m (in a diaphragm type capacitive sensor), separation between the fixed and
movable plate is 0.4cm in normal condition & the diaphragm is kept out with a tension of 4kg/ cm 2. What is the
change in capacitance for an input differential pressure of 1kg/ cm2? 5 [Estimated time: 5mins]
b) A capacitive transducer has two plates of area 10cm2 each, separated by an air gap of 4mm.
What will be the displacement sensitivity (in pF/cm) due to gap change? 5 [Estimated time: 5mins]
16. A quartz crystal having a thickness of 2mm and voltage sensitivity of 0.55V-m/N is subjected to a pressure of 1.5mN/
m2. If permittivity 40.6 x 10-12F/m, what will be the output voltage? 5 [Estimated time: 5mins]
17. A piezoelectric crystal type 60MPa full scale pressure sensor with built in electronics has a sensitivity of
200mV/MPa. If this sensor is subjected to a static pressure of 20MPa then what will be its output? 5 [Estimated time:
5mins]
18. A quartz crystal ( young’s modulus, E=9x1010N/ m2) with piezoelectric properties has a diameter of 100mm and
thickness of 4mm. Its voltage sensitivity constant is 4800V/μm. If the voltage output is 129.6V, what is the applied
load? 5 [Estimated time: 5mins]
19. a) Why 3-wire is advantageous over 2-wire. 5 [Estimated time: 6mins]
b) State the different materials of thermistor? Explain sintering process? 2+3 [Estimated time: 5mins]
20. Why thermistor is more sensitive than RTD? Explain. Draw the characteristic of thermistor. What is temperature
range of it? What are PGT and NGT? 4+3+1+2 [Estimated time: 12mins]
21. What is thermocouple? Explain the three thermocouple laws? 2+6 [Estimated time: 10mins]
22. a) What is thermo-well? Why this is used? What are the materials of this? What is compensating cable?
1+1+1+2 [Estimated time: 5mins]
b) What are the different types of CJC? 2 [Estimated time: 5mins]
c) A PRT has a resistance of 100Ω at 25˚C. The temperature coefficient of resistance of Pt is
0.004/˚C. What is the resistance at 125˚C? 3 [Estimated time: 4mins]
23. a) For a certain thermistor, β=3140K and the resistance at 27˚C is known to be 1050Ω. The thermistor is used for
temperature measurement and the resistance measured is given by 2330Ω. Find the measured temperature.
4 [Estimated time: 5mins]
b) A PRT has a resistance of 140.5 and 100Ω at 100 and 0˚C respectively. If its resistance
becomes 305.3Ω when it is in contact with a hot gas, determine the temperature of the gas. The
temperature coefficient of Pt is 0.0039/˚C. 3 [Estimated time: 3mins]
c) A PRT has a resistance of 100Ω at 25oC. The temperature coefficient of resistance of platinum
is 0.004/ oC . What is the value of resistance at 125 oC? 3 [Estimated time: 4mins]

MODULE- 2 [PART-C]

1. Explain the objectives of automatic control system? 2 [Estimated time : 3 min ]

2.Explain the difference between open and closed- loop control. 3 [Estimated time : 4 min ]
3.Discuss an example of a close loop control system, mentioning the different variables. 4
[Estimated time : 4 min ]
4.Explain Servo operation and Regulatory operation? 5 [Estimated time :6 min ]
5.Define manipulated variable? Give an example with practical process. 3 [Estimated time : 3 min ]
6.Define Controlled variable? Give an example with practical process. 3 [Estimated time : 3 min ]
7.Define Load variable? Give an example with practical process. 3 [Estimated time : 3 min ]
8.Consider a transport lag process with a transfer function The process is controlled by a purely integral
controller with transfer function in a unity feedback configuration. The value of Kj for which the
closed loop plant has a pole at s = -1, is ______ . 2 [GATE 2014] [Estimated time : 3 min ]
9. Explain the ON-OFF controller characteristics with differential gap. 3 [Estimated time : 3 min ]
10. Define offset of a process output ? Show the effect of P controller for a unity feedback close loop system (Taking
K
plant as a simple first order lag process with Transfer function ) on time response and generation of offset.
1+ S
1+4 [Estimated time : 6 min ]
11.What are the different techniques for minimizing offset of process controlled variable. 3
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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
[Estimated time : 4 min ]
2
12.The transfer functions of a first order plant G ( s ) = . It is used in a unity feedback system with a proportional
1 + 2S
controller of proportional band 50%. Find the steady state error for a unit step input, and the time constant of the
closed loop system. 5 [Estimated time :5 min ]
1
13. A second order process transfer function given by G(S ) = is consider for unity negative
(1s + 1)( 2 s + 1)
feedback operation. A proportional (P) and proportional-derivative(PD) controller are considered separately , having
transfer function GC ( S ) = K P and GC ( S ) = K P (1 + Td S ) respectively . Compare their time response and
stability. 3+4 [Estimated time : 10 min ]
14. Describe the effect of I control and PI control separately on time response for close loop 1 st order lag process having
 k 
T.F=   with unity gain negative loop feedback system. 5 [Estimated time : 6 min ]
 1+ s 
15.Discuss the effect of P control and PD control separately on time response of a close loop second order process with
 1 
T.F=  2 
with unity gain negative loop feedback system. 5 [Estimated time : 5 min ]
 JS 
16.What is meant by reset time and rate time of a PID controller? Find the transfer function of a PID controller which has
proportional band of 50%, reset time is 3 seconds. and rate time is 2 seconds. 1+4
[GATE: 2004] [Estimated time : 5 min ]
17. What is process reaction curve? How it can be obtained for a particular process. 2+1 [Estimated time : 2 min ]
18.What performance criterion should be used for the selection and tuning of controller? 3 [Estimated time : 2 min ]
19.*From S curve of a process which parameters are required to calculate for controller tuning. 4 [Estimated time : 3 min ]
20.Define ultimate gain of a controller. 2 [Estimated time : 2 min ]
21.Define One-quarter decay ratio. 2 [Estimated time : 2 min ]
22.What are the basic elements of pneumatic controller? 2 [Estimated time : 2 min ]
23. What is pneumatic relay? What are the different types of pneumatic relay? 1 +1 [Estimated time : 2 min ]
24.Explain the reason for integral (I) action in pneumatic controller. How gain can be varied? 3+1Estimated time: 4 min ]
25.Explain the reason of proportional (P) action in pneumatic controller. How gain can be varied? 3+1
[Estimated time : 4 min ]
26.Explain the reason of Derivative (D) action in pneumatic controller. How gain can be varied? 3+1
[Estimated time : 4 min ]
27.How Schmitt trigger circuit act as ON/OFF controller. How ON and OFF condition is set. 4+1 Estimated time : 4 min ]
28. Around a single op-amp, design an on-off controller with neutral zone of 4V and central voltage of 3.2V. Vsat =10V
.Find the voltages corresponding to VUTP and VLTP . Assume output is – Vsat when Vin is very high. 4
[Estimated time : 3 min ]
29. An op-amp 741 configured as Schmitt trigger is supplied with a measure and varying sinusoidaly around 2V with
peak to peak variation of 2V.Design the circuit to realize on-off controller with neutral zone of +0.2V around 2V.
4 [Estimated time : 3 min ]
30.Why the electronic controller preferred over pneumatic controller? 3 [Estimated time : 2 min ]
31.How the output range is selected for a flapper nozzle system? 3 [Estimated time : 3 min ]
32.How the controller gain varied for electronics P+I controller. 3 [Estimated time : 3 min ]
33.How the controller gain varied for electronics P+D controller. 3 [Estimated time : 3 min ]
The temperature range of a temperature controller is 225 °C to 500 °C. Set point is kept at 350 °C. Find the percent of
span error when the temperature is a) 350 °C b) 400 °C c) 450 °C. . Calculate the measured value as percentage of
measurement range. 5 [Estimated time : 5 min ]
34. It is desire to check experimentally the calibration of a PD controller. Input is subjected to a linear change of
10%/min. The corresponding output is observed to undergo an initial step change of 5% followed by a gradual
change of 2%. Determine the gain KP and KD. 5 [Estimated time : 5 min ]
35.a) A PI controller indicates an output of 14 mA when the error is zero. Set point is suddenly increased to 18 mA and
the controller output is recorded and is given below . Find Kp and TI. 5 [Estimated time : 5 min ]
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Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
Time (t, sec) 0 10 20 30
Output (mA) 18 20 22 24
b) Suppose the error signal shown in Fig. is applied to a PD controller with K p = 10, KD =0.6 and m0 = 20% . Draw
the graph of the resulting controller output. 5 [Estimated time : 5 min ]

36.A proportional controller has a transfer

function of 15%/% and a set point of 50%
output. It outputs to a valve which at the set
point allows a flow of 200m3/sec . The valve
changes it output by 4m3/sec for each percent of controller output. What will be the controller output and offset error
when the flow has to be changed to 240m3/sec? 5 [Estimated time : 5 min ]
37. Explain the Electronic ON/OFF controller using comparator as basic element. How ON and OFF condition is set
and differential gap can be varied. 5 [Estimated time : 5 min ]
38.Design a motor speed control system with a proportional band of 45%. Speed varies from 100-150 rpm and the
controller output is (0-5)V for this range. A speed transducer linearly changes its output from (2-5)Vover the same
speed range. Set point of 125 rpm is desired. 5 [Estimated time : 5 min ]
39. Design an ON-OFF controller around a single op-amp with natural zone of 4V and central voltage of 3.2V, V sat=10 V
. Find the voltage corresponding to VUTP and VLTP. 5 [Estimated time : 5 min ]
40.Explain process reaction curve(PRC) for a physical process? ? Sketch the S-curve and mention different parameters of
PRC. 2+ 6 [Estimated time : 5 min ]

MODULE- 3 [PART-C]
1.Define ratio control. Discusses how different way ratio control can be achieved. 2 + 4
[Estimated time : 6 min ]
2.Describe the main features of cascade control. 3 [Estimated time : 3 min ]
3.Describe the thumb rule for designing and tuning of cascade control. 3 [Estimated time : 4 min ]
4. Explain the feedforward control scheme of distillation column with P & I diagram. 5
[Estimated time : 10 min ]
5.Describe generalize design procedure for feedforward control with unity transfer function for measuring and final
control element. 4 [Estimated time : 6 min ]
6. Describe generalize design procedure for feedforward control with measuring device and final control element. 4
[Estimated time : 6 min ]
7.Explain the control strategy of a liquid mixing process using ratio control. 5 [Estimated time : 6 min ]
8. Explain the control strategy using ratio control for wastewater neutralization. 5 [Estimated time : 8 min ]
9.When cascade control will give improved performance than conventional feedback control?
Describe with an example. 4 [Estimated time : 6 min ]
10.*Draw the diagram of cascade control loop. How it is differ from feedback control loop. 3 [Estimated time : 4 min ]
11. Explain how cascade control differ from feedback control ? 3 [Estimated time : 4 min ]
12.Explain the purpose of cascade control for heat exchangers with schematic? 4 [Estimated time : 7 min ]
13.Define Multivariable Control? Describe multivariable control using in CSTR. 1+ 4 [Estimated time : 8 min ]
14. Develop a process model for multivariable system analysis without and with process disturbance. 5 [Estimated time : 8
min ]
15.a) Explain the difference between feed-back and feed-forward control.
b) Explain the feed-forward control with an example. 3+5=8
16.What is Multivariable Control? Give an example of a Multivariable control using in a Process. 2+5=7
17.Explain 3-element boiler drum level control as multiloop control. 5

MODULE- 4 [PART-C]
1.Discusses the purpose of actuators in process control application? 3
[Estimated time : 5 min ]
2.*How does flow rate affect the differential pressure drop across the control valve. Explain with pressure profile across
the valve. 4 [Estimated time : 6min ]
20
Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
3. Compare the sensitivities of the three valve characteristics 4. [Estimated time : 5 min ]
4. Determine the flow characteristic equation and draw the characteristic curve for Equal % valve. What is the plug type
for this type of valve. 4+1 [Estimated time :6 min ]
5.Explain differences between inherent and installed valve characteristic. 4 [Estimated time : 5 min ]
6.Explain the operation of relay type electric motor actuator with diagram. 4 [Estimated time : 6 min ]
7.Explain the basic function of pneumatic actuator with schematic. 5 [Estimated time : 6 min ]
8.Explain the function of electric actuator with schematic. 5 [Estimated time : 8 min ]
9. Discusses about different types of control valves according to their construction? 5 [Estimated time : 10 min ]
10.Explain the purpose of valve positioner in a control valve with schematic. 4 [Estimated time : 6 min ]
11.Discusses about the different characteristics of control valve? 4 [Estimated time : 6 min ]
12.Explain the types of plugs according to valve flow characteristic. 5 [Estimated time : 8 min ]
13.Define “Linear” control valve. 2 [Estimated time : 2 min ]
14.Define “equal percentage” in the equal percentage valve? 2 [Estimated time : 2 min ]
15.Define the “quick opening” control valve. 2 [Estimated time : 2 min ]
16.Explain the need of I/P converter in a control system? 2 [Estimated time : 4 min ]
17.*Describe the operation of I/P converter with schematic. 4 [Estimated time : 8 min ]
18.Explain basic operation of rotating shaft type control valves? 3 [Estimated time : 4 min ]
19.Discusses about the use of single seated valve and double seated valve? 4 [Estimated time : 5 min ]
20.What is pneumatic relay? How many types of pneumatic relay are used in pneumatic controller? Describe with net
sketch any one type of pneumatic relay. 1 + 2 +4=7
21.Give a labeled neat sketch of a single seated and double seated control valve. 5
22.An equal percentage valve has a maximum flow of 50m 3/hr and a minimum flow of 2m3/hr. if the full stem travel is
3 cm, find the flow through the valve for a stem travel of 1cm. what is the rangeability of the valve? 5

MODULE- 5,6 [PART-C]

14. Define PLC according to NEMA. 2 [Estimated time : 2 min ]
15. Discusses about the different types of PLC? 3 [Estimated time : 3 min ]
16. *Discusses Central Processing Unit (CPU) part of PLC with schematic? 5 [Estimated time : 8 min ]
17. Define the SCAN time of PLC ? What is the unit of scan rate? 1+1 [Estimated time : 2 min ]
18. What type of programmable language used in PLC? Why this kind of programming developed?
1 + 2 [Estimated time : 3 min ]
19. Describe the function of different file or bit storage unit of PLC memory. 5[Estimated time : 8 min ]
20. Discusses about the different types of Timers in a PLC? 4 [Estimated time : 6 min ]
21. Discusses about the different types of counters in a PLC? 3 [Estimated time : 5 min ]
22. Discusses about the basic difference between PLC and DCS? 2 [Estimated time : 4 min ]
23. What are the different memory available in a PLC? 2 [Estimated time : 3 min ]
24. Draw the ladder logic of logic gate NAND, NOR, X-OR , X-NOR . 5 [Estimated time : 8 min ]
25. Draw the ladder logic of 4:1 Multiplexer with I/Os detail. 5 [Estimated time : 6 min ]
26. Draw the ladder logic with I/Os detail of 4:1 Multiplexer implemented with two 2:1 MUX and a OR gate. 5
[Estimated time : 6 min ]
27. Develop the ladder program with I/Os detail for the following conditions:
A railway station has 3 platform A,B and C. A train is coming into the station. It has to be given entry to platform A if
platform A is empty. If both platform A and B are occupied then it has to be given entry to platform C. If all the
platforms are full then the train has to wait until any platform without any train. 5 [Estimated time : 6 min ]

28. Develop ladder program with I/Os detail and timing diagram for the following condition:
Start push button starts motor1, after 10 sec. motor1 off and motor2 on. Stop switch stops motor2. 5
[Estimated time : 6 min ]
29. Develop ladder program with I/Os detail and timing diagram for the following condition:
Motor1 (M1) starts as soon as start switch is on. After 10 sec. M1 goes off and M2(motor2) starts after 5 sec. M2 goes
off and M3(motor3) starts. After 10 sec. M3 off and M1 starts and repeat the cycle. 5 [Estimated time : 6 min ]
30. Describe the different stages of PLC executive software with the help of flowchart. 5 [Estimated time : 6 min ]

21
Prof. Jayjeet Sarkar
Dept. of Electronics & Communication Engineering
31. There are three machines, each with its won start and stop switch (both are push button type switch).Only two of three
machines can run at a time. Draw the ladder program with appropriate interlocking .Mention input output details for the
ladder program. 5 [Estimated time : 6 min ]
32. What are the different memory available in a PLC and mention their purpose? Describe the processor section of a PLC
with relevant diagram. 4+6 [Estimated time : 10 min ]
33. Develop a ladder program – Stacking 5 boxes and bonding then with a wrapper.
(a) From box preset signal , count 5 boxes(I:0/1)
(b) Turn ON the wrapper master control relay (O:0/1) for 5 second.
(c) Go to step (a) . 5 [Estimated time : 6 min ]
34. Develop a ladder program for a circuit that flashes two lights alternatively 5 second ON and 5 second OFF continuously.
Mention I/Os and functions detail used in Ladder program. Show the timing diagram of I/Ps and O/Ps with status bit of
timer functions. 5 [Estimated time : 10 min ]
35. [Estimated time : 10 min ]
36. Compare between different communication mode of Master-Slave , Token passing and random access. 5 [Estimated time
: 6 min ]
37. What are the different communication infrastructure on the area control network supports as a data highway design in
DCS system. 5 [Estimated time : 10 min ]
38. Describe the DCS I&C with schematic with different operating areas. 10 [Estimated time : 10 min ]
39. What is the baasic purpose of data link layer in a OSI model. Describe the different regulating access used by the data
link layer. 1+6 [Estimated time : 10 min ]

_______________________________
Prepared by
Prof. Jayjeet Sarkar, (Subject Teacher)

22