Chemical Engineering - Process Control and Instrumentation
Exercise :: Process Control and Instrumentation - Section 5
1.
Time constant is the
A.
time taken by the controlled variable to reach 63.2% of its full change. B.
same as transportation lag. C.
same as dead time. D.
time required by the measured variable to reach 63.2% of its ultimate change.
Answer: Option A
Explanation:
2.
Mercury manometer (U-tube type) exemplifies a __________ order system.
Answer: Option C
Explanation:
3.
Emf developed by a thermocouple while measuring a temperature of 400°C is 22 mV. The type of thermocouple used is
A.
chromel-alumel B.
iron-constantan C.
platinum-rhodium D.
platinum-platinum+rhyodium
Answer: Option B
Explanation:
4.
Bode stability method uses __________ loop transfer function.
A.
open B.
closed C.
either (a) or (b) D.
neither (a) nor (b)
Answer: Option A
Explanation:
5.
Working principle of bimetallic thermometers is difference in linear co-efficient of thermal expansion of two strips of different metals welded together. Which of the following has the maximum thermal co-efficient of linear expansion?
Answer: Option B
Explanation: