Deck 27: Instrumentation

Question 1

What is a possible equipment impact of adjusting leaking control valve packing?

A) Shutdown of process unit
B) Damage to motor
C) Valve may not open, close, or operate properly
D) Possible damage to downstream equipment due to higher flows and pressures

Answer 1

C
Explanation: A) Incorrect. Adjusting leaking control valve packing may cause the valve to not open, close, or operate properly.
B) Incorrect. Adjusting leaking control valve packing may cause the valve to not open, close, or operate properly.
C) Correct. Adjusting leaking control valve packing may cause the valve to not open, close, or operate properly.
D) Incorrect. Adjusting leaking control valve packing may cause the valve to not open, close, or operate properly.

Question 2

What is a measurement of the chemical or physical properties of a substance?

A) Remote
B) Process variable
C) Analytical variable
D) Transducer

Answer 2

C
Explanation: A) Incorrect. A remote is instrumentation that is located away from the process (e.g., in a control room) and is controlled by the DCS or other panel board mounted controller.
B) Incorrect. A process variable is a varying operational condition that is associated with a processing operation such as temperature, pressure, flow rate, level, and composition.
C) Correct. An analytical variable is a measurement of the chemical or physical properties of a substance.
D) Incorrect. A transducer is the control loop component that converts one instrumentation signal type to another type (e.g., electronic to pneumatic).

Question 3

Which of the following is an instrument used to document variables such as pressure, speed, flow, temperature, level, and electrical units?

A) Sensor
B) Indicator
C) Recorder
D) Controller

Answer 3

C
Explanation: A) Incorrect. A sensor is an element in direct contact with the process variable to be measured that senses a change and provides a signal to the transmitter.
B) Incorrect. An indicator shows the current condition of a process variable, usually through a visual representation such as a needle on a scale in a gauge or a digital readout.
C) Correct. A recorder is an instrument used to document variables such as pressure, speed, flow, temperature, level, and electrical units.
D) Incorrect. The controller receives information from the transmitter in the form of a pneumatic or electronic signal, compares that input signal to the reference set point, and sends a corrective output signal to the final control element, typically a control valve.

Question 4

Which of the following is a common flow-sensing element that creates a difference in pressure that can be measured by a D/P cell?

A) Rotating piston
B) Oval gear
C) Orifice plates
D) Rotating vane meters

Question 5

What is the difference between the set point and the current process variable value called?

A) Error
B) Excess
C) Oversight
D) Set point

Question 6

What component of process control instrumentation systems converts one instrumentation signal type into another type?

A) Alarm
B) Control valve
C) Transducer
D) Valve positioner

Question 7

What is a varying operational condition that is associated with a processing operation such as temperature, pressure, flow rate, level, and composition?

A) Remote
B) Process variable
C) Analytical variable
D) Transducer

Question 8

What system uses light frequency signals and is gaining popularity in industry use?

A) Fiber optics
B) Pneumatic signals
C) Compression signals
D) Hydraulic signals

Question 9

What is the most common pressure measurement found in the US process industry?

A) Differential pressure (psid)
B) Pounds per square inch (psi)
C) Inches of mercury (inHg)
D) Pounds per square inch absolute (psia)

Question 10

What is the main signal for process instrumentation lines and control loop instruments?

A) Hydroelectric power
B) Electricity
C) Solar power
D) Pneumatic power

Question 11

What type of control element can only be on or off?

A) Discrete
B) Modulated
C) Valve control
D) Continuous

Question 12

What type of signal is a continuously variable representation of a process variable?

A) Analog signal
B) Process signal
C) Digital signal
D) Automatic signal

Question 13

Which of the following is an element in direct contact with the process variable to be measured that senses a change and provides a signal to the transmitter?

A) Sensor
B) Indicator
C) Recorder
D) Controller

Question 14

Which of the following improper operations could most likely lead to hand and/or back injuries?

A) Bypassing alarms
B) Failure to respond to an alarm
C) Adjusting leaking control valve packing
D) Attempting to open a motor controlled valve manually

Question 15

Which of the following improper operations will not cause equipment shutdown?

A) Bypassing alarms
B) Failure to respond to an alarm
C) Partially opening a bypass valve around a working control valve
D) Turning off air supplies to control devices

Question 16

Which of the following is an example of instrumentation that could be programmed to begin each step in the process upon completion of the previous one?

A) Filter backwash
B) Dryer regeneration
C) Regeneration of a catalyst bed
D) All of the above

Question 17

Which of the following is a temperature-sensing instrument?

A) Thermistors
B) Manometers
C) Radar gauges
D) All of the above

Question 18

What uses air pressure, or a gas such as nitrogen, as a power source traveling through copper or stainless tubes?

A) Analog signal
B) Digital signal
C) Hydraulic instruments
D) Pneumatic instruments

Question 19

What common component of a DCS system is a data highway that connects the systems?

A) Network
B) Workstations
C) Central processor
D) Supervisory computers

Question 20

What common component of a DCS system are computers accessed by engineers and management at the programming level to monitor production targets?

A) Network
B) Workstations
C) Central processor
D) Supervisory computers

Question 21

Which of the following is a symbol for remotely mounted instrumentation?

A)
B)
C)
D)

Question 22

Which of the following is the symbol for a hydraulic signal?

A)
B)
C)
D)

Question 23

Which of the following is the symbol for a pneumatic signal?

A)
B)
C)
D)

Question 24

Which of the following is a symbol for panel mounted instrumentation?

A)
B)
C)
D)