PO Instrumentation & Measurement 3

Question 1

In a 4–20 mA instrumentation loop, what percentage of the process range does a signal of 12 mA represent?

Accepted Answer

50%

Answer

25%

Answer

60%

Answer

75%

Question 2

What does HART stand for in the context of industrial instrumentation communication?

Accepted Answer

Highway Addressable Remote Transducer

Answer

High Accuracy Remote Transducer

Answer

Hybrid Analog Relay Technology

Answer

High-speed Automated Remote Transmitter

Question 3

What is 'dead band' as it applies to process instrumentation and control?

Accepted Answer

A range of input change over which the instrument produces no change in output

Answer

The maximum allowable measurement span of a transmitter

Answer

The signal level below which an instrument automatically powers down

Answer

A physical safety exclusion zone established around high-pressure instruments

Question 4

What type of pressure measurement references local atmospheric pressure as its zero baseline?

Accepted Answer

Gauge pressure

Answer

Absolute pressure

Answer

Differential pressure

Answer

Vacuum pressure

Question 5

What is the purpose of impulse lines (sensing lines) connecting a process tap to a pressure instrument?

Accepted Answer

To physically transmit process pressure or fluid from the process connection to the instrument

Answer

To carry electrical power from the control room to the field transmitter

Answer

To provide the HART digital communication path between field devices

Answer

To drain condensate away from control valve actuators

Question 6

What is the primary function of a solenoid valve in a process instrumentation and control system?

Accepted Answer

To provide on/off control of fluid flow using an electromagnetic coil

Answer

To measure the volumetric flow rate of a process fluid

Answer

To continuously throttle flow in proportion to a 4-20 mA control signal

Answer

To convert process pressure into an electrical milliamp signal

Question 7

Which action should an operator take first when an instrument reading appears suspect or inconsistent with other process indicators?

Accepted Answer

Verify the instrument by cross-checking with an independent measurement or secondary indicator

Answer

Immediately adjust the process setpoint to compensate for the reading

Answer

Replace the instrument transmitter without further investigation

Answer

Shut down the process unit to prevent a potential hazard