Download Unit 1 QN Questions Marks Unit No. BLOOMS Level (1

Unit 1
QN
Questions
1.
Write short note on
1. Process control principle.
2. Human aided control system
3. Automatic Control
4. Servo mechanism
5. Supervisory Control
6. DDC
7. Smart sensors
How a control system is evaluated and what are the
objectives of typical control system?
2.
4 or 6
each
1
BLOOM
S Level
(1-6)
2
6
1
Marks
Unit
No.
CO
1
Definition:1
Figure: 1 or 2
Explanation: 2
or 4
2
1
Evaluation
criteria: 2
Explanation:
Figure: 2
Explanation:
Figure: 2
Explanation:
Definition:2
Explanation:
3.
Explain the concept of stability in control system.
6
1
1
1
4.
How a control system is evaluated to ensure stability?
6
1
2
1
5.
Explain analog control and digital control with relation
to automation
6
1
1
1
Define automation and explain the architecture of
automation.
Explain reasons for automation along with advantages,
disadvantages.
6
1
1
1
6
1
1
1
8.
Define automation and explain types of automation.
6
1
1
1
9.
What are the effects of modern developments on Global
competitiveness?
The tank in fig. below has relationship between flow and
6.
7.
10.
level given by
Qout  K h
where h is in feet and
K=1.156(gal/min)/ft2. Suppose the input flow rate is
2gal/min. At what value of h will the level stabilize from
self regulation?
3
3
1
Marking
Scheme
3
1
4
4
4
4
Definition:2
Explanation: 4
Reasons: 2
Advantages:2
Disadvantages:2
Definition:2
Explanation: 4
Explanation: 6
Stepwise
answer is
expected
Unit 2
BLOOM
S Level
(1-6)
1
Marks
Unit
No.
Explain need for signal transmission in
automation.
Explain electrical transmission systems along
with advantages and disadvantages.
4
2
3.
Explain current telemetry. What is advantage of
current telemetry over voltage telemetry?
6
2
2
2
4.
Explain voltage transmission of signals along
with advantages and disadvantages.
6
2
2
2
5.
Explain 2- wire and 3- wire transmitters in detail.
6
2
2
2
6.
What is significance of pneumatic signal
transmission?
How the pneumatic signal is transmitted?
Explain any one pneumatic signal transmission
technique
Write short notes on
1. DPT
2. Electronic DP cell
3. Smart transmitters
4. Digital sensors
What is sensor compensation and linearization
technique? Why it is necessary?
A temperature sensor, thermocouple, gives a
voltage proportional to temperature with a
sensitivity 0.5 mv/oC. The sensor has an output
resistance of 2.0 kΩ. If the sensor is connected to
an amplifier with an input resistance of 5 kΩ and
gain of 200, find the amplifier output for a
temperature of 100oC,
a. Neglecting the loading effects.
b. Taking loading effects into account.
The resistance of sensor varies from 5 kΩ to 20
kΩ for a dynamic variable over a range. If the
sensor is connected in a divider circuit with
constant resistance of 15 kΩ and supply voltage
10V, then find
a. The minimum and maximum of output
voltage,
b. The range of output impedance,
c. The range of power dissipated by the
sensor.
A Wheatstone bridge circuit has resistance of
R1= R2= R3=5.00 KΩ and R4= 5.5 KΩ and a
10.00 V power supply. If a galvanometer with a
100 Ω internal resistance is used for a detector,
find the offset current.
A current balance bridge, as shown in figure
below, has resistors R1= R2= 15 KΩ and R3=2
KΩ, R4=1.5KΩ. Assuming the impedance of the
null detector very high, find the current required
4
2
2
2
8
2
2
2
QN
Questions
1.
2.
7.
8.
9.
10.
11.
12.
13.
8
CO
Making
Scheme
2
Explanation: 4
2
Explanation: 4
Advantages:2
Disadvantages:2
Figure: 2
Explanation: 3
Advantages:1
Figure: 2
Explanation: 2
Advantages:1
Disadvantages:1
Figure: 2
Explanation: 4
Explanation: 4
Explanation: 4
Figure:2
Types:2
Definition:1
Figure: 1 or 2
Explanation: 2
or 4
4 or 6
each
2
1
1
6
2
2
1
Explanation: 4
Necessity:2
6
2
3
1
Stepwise
answer is
expected
6
2
2
1
Stepwise
answer is
expected
6
2
2
1
Stepwise
answer is
expected
6
2
2
1
Stepwise
answer is
expected
QN
Questions
Marks
Unit
No.
BLOOM
S Level
(1-6)
CO
Making
Scheme
to null the bridge if R3 changes by 5Ω. The
supply voltage is 10V.
14. A current balance bridge, shown in figure beloe
has R1= R2= 5 KΩ and R3=2 KΩ, R4=1800Ω,
R5=200Ω and a high impedance null detector.
Fond the current required to null the bridge if R3
changes by 5Ω. The supply voltage is 10V.
6
2
2
1
Stepwise
answer is
expected
15. Temperature is to be measure in the range of
250oC to 450oC with an accuracy of +2oC. The
sensor is a resistance that varies linearly from
280Ω to 1060Ω for this temperature range.
Power dissipated in the sensor must be kept
below 5mW. Develop a analog signal
conditioning that provides a voltage varying
linearly from -5 to+5V for this temperature
range. The load is a high impedance recorder.
16. A process signal varies from 4 to 20 mA.
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
The set point is 9.5 mA. Use a current-tovoltage converter and summing amplifier to
get a voltage error signal with a scale factor
of 0.5V/mA.
17. Sensor resistor varies from 25 to 1.5kΩ as a
variable changes from 𝐶𝑚𝑖𝑛 to 𝐶𝑚𝑎𝑥 . Design a
signal conditioning system that provides an
output voltage varying from -2 to +2V as the
variable changes from min to max. Power
Dissipation in the sensor must be kept below
2.5mW.
18. A pressure sensor output s a voltage varying
as a 100 mA/psi and has 2.5 kΩ output
impedance. Develop a signal conditioning to
provide 0 to 2.5 V as the pressure varies 50
to 150 psi.
19. Temperature is measured by a sensor with an
output of 0.02V/oC. Determine the required
ADC reference and word size to measure 0o to
100oC with 0.1oC resolution.
20. A measurement of temperature using a sensor
that outputs 6.5mV/oC must measure to 100oC. A
6-bit ADC with a 10V reference is used.
a. Develop a circuit to interface the sensor
and the ADC.
b. Find the temperature resolution.
6
2
BLOOM
S Level
(1-6)
3
21. Pressure from 50 to 400psi is converted to
voltage
by
the
relation
1/ 2
V  0.385[ P]  2.722 This is input to an
ADC with 5V reference, which provides 00H to
FFH over the pressure range. A program uses
instruction DV=UDF(1) to input data from the
ADC as base 10 number DV that varies from 0 to
255 over the pressure range. Develop a
linearization equation to give a quantity p, in the
program that is equal to the actual pressure.
22. A sensor provides temperature data as
360μV/oC. Develop a comparator circuit that
goes high when the temperature reaches
530oC.
23. A DAS has an ADC of 8 bits with a 0 to 2.5 V
range of input for 00H to FFH output (i.e. , FEH
to FFH occurs at 2.50V). Inputs are temperature
from 20oC to 10020oC scaled at 40mV/oC,
pressure from 1 to 100 psi scaled at 100mV/psi,
and flow from 30 to 90 gal/min scaled at 150
mV/(gal/min). Develop a block diagram of the
required signal conditioning so that each of these
can be connected to the DAS and so that the
indicated variable range corresponds
to 00H
to FFH. Specify the resolution of each in terms
of the change in each variable that corresponds
to an LSB change in the ADC output.
24. A digital control systems is to provide regulation
of pressure within 1.2kPa in the range of 30 to
780 kPa. How many bits must be used for the
data acquisition?
25. A type-K TC with 20oC reference will be used to
measure temperature from 200oC to 280oC in a
computer controller application. The data
acquisition hardware and software make the
actual measure voltage, in a mV, available in
software as a variable VTC. Devise a flowchart
and/or program in the language of your choice
that makes the reference correction and performs
linearization by table look-up interpolation. Use
table values in 5oC increments for a type K TC
with a 0oC reference.
26. A pressure sensor outputs 2.5mV/kPa, but there
is 60Hz noise of a steady peak 55mV on the line.
Pressure in the range 0.0 to 70kPa must be
converted by an ADC and presented to a
computer. The resolution must be at least
0.2kPa.
a. Design a system of filter, signal
6
2
6
QN
Questions
Marks
Unit
No.
CO
Making
Scheme
1
Stepwise
answer is
expected
3
1
Stepwise
answer is
expected
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
6
2
3
1
Stepwise
answer is
expected
QN
Questions
conditioning, and ADC specifications to
satisfy this requirement.
b. Suppose the pressure suddenly changed
from 20 to 50kPa. How long would it be
before the ADC presented the correct
digital signal for this pressure to the
computer?
27. A system is presented in fig. below to provide
computer temperature control. The heater
requires a voltage from 0.0 to 5.0V for OFF
(0%) to full ON (100%). The following
algorithm
will be used by the computer to
determine the heater setting:
Marks
6
Unit
No.
2
BLOOM
S Level
(1-6)
CO
3
1
Making
Scheme
Stepwise
answer is
expected
Unit 3
QN
Questions
Marks
Unit
No.
3
BLOOM
S Level
(1-6)
2
CO
1.
Explain PID controller in detail
8
2.
3.
What is Integral windup?
What is proportional controller? What are its
advantages and disadvantages?
4
6
3
3
2
2
1
1
4.
What is PI controller? What are its advantages and
disadvantages?
6
3
2
1
5.
What is PD controller? What are its advantages
and disadvantages?
6
3
2
1
6.
7.
Why derivative controller is not use alone?
What are the tuning methods of PID controller?
2
8
3
3
2
3
1
1
8.
What is digital PID? Explain in detail with
algorithm
8
3
2
1
9.
What is analog PID? Explain in detail with
appropriate circuit diagram
8
3
2
1
10.
Explain cascade control with suitable example.
8
3
2
1
11.
Explain Microprocessor based
suitable examples.
with
8
3
2
1
12.
An 8-bit DAC has a Vref of 10 V. The binary input
is 10011011. Find the analog output voltage.
4
3
2
1
Stepwise
answer is
expected
13.
Explain PAC in detail.
8
3
2
1
14.
Explain different types of mechanical switches
6
3
1
1
15.
Explain VFD along with energy conservation
8
3
2
1
6 each
3
2
1
Definition:2
Figure: 2
Explanation: 4
Explanation: 2
Advantages:2
Disadvantages:2
Figure: 2
Explanation: 4
Energy
conservation:2
Definition:1
Figure: 2
Explanation: 3
8
3
2
1
Principle: 2
Explanation: 4
Examples:2
4
3
3
1
Stepwise
answer is
expected
control
1
Marking
Scheme
scheme through VFD
16.
Write short notes on
1. Stepper Motor
Definition:2
Figure: 2
Explanation: 4
Explanation: 4
Explanation: 2
Advantages:2
Disadvantages:2
Explanation: 2
Advantages:2
Disadvantages:2
Explanation: 2
Advantages:2
Disadvantages:2
Explanation: 2
Explanation: 4
Types:4
Definition:2
Figure: 2
Explanation: 4
Definition:2
Figure: 2
Explanation: 4
Definition:2
Figure: 2
Explanation: 4
Definition:2
Figure: 2
Explanation: 4
2. Servo motor
3. BLDC motor
17.
On what principle pneumatic actuators work?
Explain pneumatic actuators with suitable examples
18.
Suppose a force of 400N must be applied to open a
valve. Find the diaphragm area if a control gauge
pressure of 70KPa (~10psi) must provide this force.
Questions
Marks
Find the working force resulting from 200N applied
4
3
BLOOM
S Level
(1-6)
3
6
3
3
QN
19.
Unit
No.
CO
Marking
Scheme
1
Stepwise
answer is
expected
1
Stepwise
answer is
expected
to a 1 cm radius forcing piston (a) If the working
piston has a radius of 6 cm. Then (b) find the
hydraulic pressure.
20.
A spring-loaded single-acting cylinder has a
diameter of 2 in. and a stroke of 2 in. The return
spring has a spring constant of 3 lb/in. The available
air pressure is 30 psi. What force can this cylinder
supply to a load at the end of its stroke?