Yashwantrao Chavan Maharashtra Open University 2006 Certification TES Instrumentation - II - Question Paper

TES112/EE/20070814
Instrumentation - II
Time : 180 minutes Marks : 100
Instructions for the students :
1. All ques. are compulsory.
2. “Long ans kind ques. (LAQ)” is a supply kind ques. of 20 marks,
which require typical ans of about 60-80 lines in about 32-40 minutes.
3. “Short ans kind ques. (SAQ)” is a supply kind ques. of five marks,
which require typical ans of about 15-20 lines in about 08-10 minutes.
4. Use of non-programmable kind of scientific calculator is allowed.
5. Draw neat diagrams wherever necessary.
6. presume suitable data if necessary.

Long ans kind ques. (LAQ’s)

1. (a) describe the subsequent terms for SCR.
i) Maximum forward current
ii) Peak reverse voltage
iii) Trigger voltage
iv) Trigger current
v) Holding current
(b) With a neat sketch, discuss the working of a continuous
operation paper thickness controlling system using
mechanical final control elements.


2. (a) define the various elements in ladder diagram with a
symbol.
(b) define proportional control mode giving improper
example.


3. (a) With a block schematic, discuss data logging system using a
commuter.
(b) discuss the subsequent parameters related to control system.
i) fault
ii) Control Lag
iii) Dead time
iv) Cycling
v) Controller modes

4. (a) Justify the statement “Cascade control often provides better
control than direct methods” with a suitable example.
(b) Write a short note on universal process control business.


Short ans kind ques. (SAQ’s)
5. A stepper motor has 100 per step and must rotate at 250 rpm.
What input pulse rate, in pulses per second, is needed ?

6. discuss integral control mode. 5
7. Design an alarm that provides a logic high of 5V when a liquid
level exceeds 4.2 m. The level has been linearly converted to a
0-10 V signal for a 0-5.0 m level.

8. What is the stability criteria for control loop ?

Earning:   Approval pending.