Process Control and Instrumentation MCQs

Question 1

Dead zone is the

Accepted Answer

Maximum change in the variable that does not change the reading of the instrument

Answer

Same as time constant

Answer

Same as transportation lag

Answer

None of these

Question 2

__________ temperature scale assigns 0° to the 'ice point' and 80° to the 'steam point'.

Accepted Answer

Reumur

Answer

Celcius

Answer

Rankine

Answer

Farenhite

Question 3

In a shell and tube heat exchanger, the outlet temperature of heating/cooling fluid is the __________ variable.

Accepted Answer

Controlled

Answer

Load

Answer

Manipulated

Answer

None of these

Question 4

Pressure of 0.01 psi (absolute) can be measured by __________ gauge.

Accepted Answer

Mcloid

Answer

Ionisation

Answer

Pirani

Answer

None of these

Question 5

Which of the following instruments is not used for measuring sub-zero (<0°) temperatures?

Accepted Answer

Radiation pyrometer

Answer

Platinum resistance thermometer

Answer

Mercury in glass thermometer

Answer

Vapor pressure thermometer

Question 6

Response of a linear control system for a change in set point is called

Accepted Answer

Servo problem

Answer

Frequency response

Answer

Transient response

Answer

Regulator problem

Question 7

Typical specifications for design stipulates the gain margin and phase margin to be respectively

Accepted Answer

> 1.7 and > 30°

Answer

< 1.7 and > 30°

Answer

< 1.7 and < 30°

Answer

> 1.7 and < 30°

Question 8

Volumetric expansion is the working principle of the __________ thermometers.

Accepted Answer

Mercury in glass

Answer

Constant volume gas

Answer

Vapor pressure

Answer

Bimetallic

Question 9

A bimetallic thermometer as compared to industrial mercury in glass thermometer has almost the same

Accepted Answer

All of the above

Answer

Temperature measuring range (- 40°C to 450°C)

Answer

Accuracy (± 1% of span)

Answer

Speed of response