Process Control and Instrumentation Subcategories

Process Control and Instrumentation

All the thermocouples used for temperature measurement use dissimilar metal ________________?

A. Strips
B. Bars
C. Wires
D. Beads

Degree to which an instrument indicates the changes in measured variable without dynamic error is called its ___________________?

A. Speed of response
B. Reproducibility
C. Fidelity
D. Static characteristics

The characteristic equation for the control system with a closed loop transfer function G1/1 + G2 is given by 1 + G2 = 0. The characteristic equation for the control system_________________?

A. Depends only upon the open loop transfer function
B. Determines its stability
C. Is the same for set point or load changes
D. All A , B & C.

Accurate temperature measurement performance of a radiation pyrometer cannot be affected, if the ?

A. Enhancement or attenuation of radiation occurs in the sighting path
B. Object and surrounding are at almost the same temperature
C. Object has varying emissivity
D. Object is transparent

The response of two tanks of same size and resistance in series is __________________?

A. Under damped
B. Critically damped
C. Over damped
D. None of the above

A sinusoidal variation in the input passing through a linear first order system _________________?

A. Becomes more oscillatory (frequency increases)
B. Becomes less oscillatory (frequency decreases)
C. Gets amplified (magnitude increases)
D. Gets attenuated (magnitude decreases)

Magnetic flowmeters are generally not used for the velocity/flow measurement of hydrocarbons due to their ?

A. Low thermal conductivity
B. Low electrical conductivity
C. High viscosity index
D. Low flash point

Which of the following is not a second order instrument ?

A. Mercury in glass thermometer with covering
B. Bare mercury in glass thermometer
C. Pressure gauge with one bellow, two tubes and a tank
D. None of these

Conversion formula for converting amplitude ratio (AR) into decibels is ________________?

A. Decibel = 20 log10 (AR)
B. Decibel = 20 loge (AR)
C. Decibel = 20 log10 (AR)0.5
D. Decibel = 20 loge (AR)0.5

A photo electric device in which the resistance of the metal is directly proportional to the light striking on it, is known as photo-conductive cell. Photoelectric transducers are used for the measurement of those parameters, which can be used to produce variation in_______________?

A. Light intensity
B. Current
C. Flux density
D. Voltage