JNTU ,B.Tech I-Semester,
Instrumentation Components, November 2008
(Electronics & Control Engineering)
1. (a) What is the coupling mechanism with operation of a cluch in an automotive?
(b) In what way are different from chain and belt drives?
(c) Enumerate the applications of friction drives.
2. (a) What is integral windup.
(b) Explain how it affects the controller performance.
3. Explain how d.c potentiometers are used for error detection and give the transfer
characteristic of potentiometers.
4. (a) With a neat diagram explain the working of 3-? stepper motor.
(b) A three- phase variable stepper motor has the following parameters.
Average Phase winding Resistance = 1 ohm
Average phase winding Inductance = 30mH
Rated winding current = 3A.
Design a simple uni polar drive circuit, such that the electrical time constant
is 2 mSec at Phase turn-on and 1 mSec. At turn-off. The stepping rate is 300
steps per second.
5. (a) Describe the important specifications of a resistor.
(b) Write short note on the following:
i. Linear resistor.
ii. Non-linear resistor.
(c) What are the different types of fixed resistors? Give the range of wattage for
6. (a) Draw the pin configuration of 725 IC and explain each pin
(b) List the applications and specifications of 725 IC
(c) Draw the configuration of 723 IC and explain the purpose of each pin.
7. (a) What is the essential difference between principle of operation of normal p-n
diode and a LED.
(b) Describe the working principle of light emitting diode with neat diagram.
(c) Draw the schematic representation of an optocoupler and explain its working
8. (a) Discuss the spectral transmittance characteristics of an absorption filter.
(b) What are the parameters to be observed in the design of grating.
(c) Give two types of mounting of grating and explain the importance of mount
in the grating.