4A Power Engineering - Unit 9: Energy Plant Instrumentation and
Controls UPDATED ACTUAL Questions and CORRECT Answers
Question: A _________ controls the flow of air through ducts or wall openings
Correct Answer: Select one: a. damper b. control valve c. fan d. pilot: a
Question: In a simple control system a process variable is measured and
Correct Answer: Select one: a. compared with a set point value b. compared with normal operating trends
c. charted in a graph d. charted in the CPU: a
Question: This type of PLC cannot be expanded
Correct Answer: Select one: a. field transmitter b. modular c. monolithic d. programmable: c
Question: Glass stem thermometers are also known as
Correct Answer: Select one: a. thermowells b. thermocouples c. liquid in glass thermometers d. filled
system thermometers: c
Question: The difference between the actual value of the measured variable and the set point is a
Correct Answer: Select one: a. disturbance b. composition c. deviation d. divination: c
Question: This type of thermostat is equipped with an open-contact switch or a snap switch
Correct Answer: Select one: a. on-off control b. two position c. modulating d. multipositon: a
Question: It is common for _________ to be attached to a pen mechanism of a chart recorder
Correct Answer: Select one: a. helical and spiral capillary tubes b. helical and spiral bourdon tubes c.
helical and spiral dampeners d. helical and spiral pig tails: b
Question: A two-terminal variable resistor used for varying current in a circuit is known as a
Correct Answer: Select one: a. potentiometer b. rheostat c. thermistor d. photoresistor: b
Question: The _________ network connects numerous controllers with the HMI consoles
Correct Answer: Select one: a. CPU b. DCS c. PCS d. ABB: b (distributed control system)
Question: For programming a HMI you must
Correct Answer: Select one: a. add a card to the HMI b. reconfigure the hard drive c. manually restart the
HMI d. plug a laptop into the HMI: d
Question: This method of flow measurement consists of a length of pipe in which the cross sectional area
converges to a minimum, then diverges to the original pipe size
Correct Answer: Select one: a. pilot tube b. venturi tube c. flow nozzle d. orifice plate: b
Question: The atmospheric gas mixture has a mass that exerts a pressure of approximately _________ on
the earth■s surface at sea level
Correct Answer: Select one: a. 99.3 b. 101.3 c. 103.1 d. 100.3: b
Question: This type of control system responds to changes in conditions regardless of whether an operator
is present
Correct Answer: Select one: a. open loop b. variable loop c. feedback loop d. closed loop: d
,Question: These can be either normally closed or normally open
Correct Answer: Select one: a. stepper valves b. drive valves c. modulating valves d. solenoid valves: d
Question: HMIs restrict operator access to
Correct Answer: Select one: a. visual/search interaction only b. start-stop operating parameters c. less
critical operating parameters d. only critical operating parameters: c
Question: In this type of control mode the control output signal is set by the human operator
Correct Answer: Select one: a. manual mode b. automatic mode with local set point c. automatic mode
with remote set point d. automatic/hand mode: a
Question: The metal bellows type and the piston type are the two types of
Correct Answer: Select one: a. electric damper operators b. pneumatic damper operators c. hydraulic
damper operators d. pilot damper operators: b
Question: The mechanism basic to all pneumatic transmitters is the
Correct Answer: Select one: a. flapper and nozzle b. nozzle and relay c. flapper and relay d. flapper and
bar: a
Question: A _________ is a device that controls large amounts of energy with small amounts of energy
Correct Answer: Select one: a. delay b. relay c. micro switch d. controller: b
Question: In this type of control mode the set point is determined locally by a human operator
Correct Answer: Select one: a. manual mode b. automatic mode with local set point c. automatic mode
with remote set point d. automatic/hand mode: b
Question: HMI is an acronym for
Correct Answer: Select one: a. human machine interaction b. human micro-processing interface c. human
machine internet d. human machine interface: d
Question: In this type of detection, the presence of the process material is detected at predetermined levels
Correct Answer: Select one: a. continuous b. single point c. uninterrupted d. sensor: b
Question: A _________ is a device that converts one form of energy into another form of energy
Correct Answer: Select one: a. transducer b. converter c. inverter d. transponder: a
Question: When the _________ and _________ are at different temperatures, the thermocouple produces a
voltage
Correct Answer: Select one: a. measuring junction / fixed junction b. measuring junction / reference
junction c. sensing junction / reference junction d. sensing junction / fixed junction: b
Question: Variable voltage signals are useful for transmitting signals
Correct Answer: Select one: a. long distances b. short distances c. near adjacent conductors d. near
flammable materials: b
Question: This measures the relative humidity of air in a room or in an air duct
Correct Answer: Select one: a. humidiscope b. humidistar c. humidistat d. humidiprobe: c
Question: PLC■s designed to be used as primary burner safeguard systems require the following
,Correct Answer: Select one: a. all control devices must fail-safe b. all listed answers c. BNS system and
program must be designed by a competent person d. must have a hard-wired watchdog timer: b
Question: This can be linked to the plant management computers, which calculate overall plant costs and
efficiencies
Correct Answer: Select one: a. the programmable computer network b. the central computer network c. the
control computer network d. the operations computer network: c
Question: Reset action, resets or returns the process variable to set point whenever error occurs in this type
of controller
Correct Answer: Select one: a. proportional b. proportional plus integral c. multi-position d. proportional
plus integral plus derivative: b
Question: The differential pressure transmitter can be used for _________ and _________ measurement
Correct Answer: Select one: a. temperature / flow b. temperature / level c. level / flow d. pressure / level: c
Question: Low pressure controllers measure and control low pressure or vacuums, measured in
Correct Answer: Select one: a. mm of light oil b. kN or mm of mercury c. mm of water d. kPa or mm of
mercury: c
Question: Programs that need occasional modifications are stored in
Correct Answer: Select one: a. EPROM b. ROM c. RAM d. EPRAM: a
Question: Hard controls on a HMI communicate with the PLC as_________ if they are not hardwired
Correct Answer: Select one: a. timer codes b. discrete or analog inputs c. field transmitters d. contact
inputs: b
Question: This is a metal sheath used to house temperature sensors
Correct Answer: Select one: a. thermometer b. thermosheild c. thermoelement d. thermowell: d
Question: Discrete digital signals are a type of
Correct Answer: Select one: a. current signal b. resistor signal c. voltage signal d. fibre optic signal: c
Question: The most common form of _________ transmission involves transmitting light along a cable
Correct Answer: Select one: a. wireless signal b. electrical signal c. pneumatic signal d. fibre optic signal:
d
Question: A pigtail _________ maintains a water seal between the steam in a boiler and the bourdon tube
in a pressure gauge
Correct Answer: Select one: a. siphon b. diaphragm c. bellows d. dampener: a
Question: This part of a control system network contains simple devices such as switches, pushbuttons, and
proximity sensors
Correct Answer: Select one: a. device bus b. field bus c. sensor bus d. smart bus: c
Question: Larger, more complex PLC■s tend to be
Correct Answer: Select one: a. modular b. monolithic c. CPU■s d. field transmitters: a
, Question: A _________ thermostat operates like an on-off type, however it has two or more switches that
operate in sequence
Correct Answer: Select one: a. modulating b. multi-position c. two position d. aquastat: b
Question: The _________ is the part of a control valve that moves the valve stem
Correct Answer: Select one: a. inlet b. bonnet c. actuator d. yoke: c
Question: Manual control is also known as
Correct Answer: Select one: a. operator control b. human contol c. forced control d. hand control: d
Question: This component of an electrical control system interrupts or diverts electrical power supply
Correct Answer: Select one: a. transmitter b. switch c. controller d. actuator: b
Question: These may receive process information via discrete voltage signals, through contact closure
inputs
Correct Answer: Select one: a. control system managers b. control system permissives c. control system
transmitters d. control system computers: d
Question: The control systems dedicated to combustion safety and operator assistance in the starting and
stopping of fuel preparation and burning equipment and for preventing misoperation of and damage to fuel
preparation and burning equipment, is the definition for
Correct Answer: Select one: a. burner management systems b. fuel management systems c. burner control
systems d. fuel control systems: a
Question: A __________ analyzes the components of a gaseous mixture or a liquid in vapor form
Correct Answer: Select one: a. chromanalyzer b. chromadectector c. chromatograph d. chromalogic: c
Question: A _________ is a change in a process that cannot be predicted
Correct Answer: Select one: a. process deviation b. process composition c. process offset d. process
disturbance: d
Question: The variable area meter is also known as a
Correct Answer: Select one: a. nutating disc meter b. rotometer c. velocometer d. Doppler meter: b
Question: This part of a control loop is used to adjust the manipulated variable
Correct Answer: Select one: a. final control element b. transmitter c. indicator d. controller: a
Question: This type of controller produces infinitely variable control output signals based on error between
process variables and set points
Correct Answer: Select one: a. non-modulating b. modulating c. non-cascading d. cascading: b
Question: These are typically variable current or variable voltage signals from pressure, level, temperature,
flow or other transmitters
Correct Answer: Select one: a. discrete inputs b. analog inputs c. pneumatic inputs d. hydraulic inputs: b
Question: A _________ is a central computer that holds a collection of data and software programs
Correct Answer: Select one: a. controller b. workstation c. server d. DCS: c
Question: These are used as electromechanical actuators in industrial control applications
Controls UPDATED ACTUAL Questions and CORRECT Answers
Question: A _________ controls the flow of air through ducts or wall openings
Correct Answer: Select one: a. damper b. control valve c. fan d. pilot: a
Question: In a simple control system a process variable is measured and
Correct Answer: Select one: a. compared with a set point value b. compared with normal operating trends
c. charted in a graph d. charted in the CPU: a
Question: This type of PLC cannot be expanded
Correct Answer: Select one: a. field transmitter b. modular c. monolithic d. programmable: c
Question: Glass stem thermometers are also known as
Correct Answer: Select one: a. thermowells b. thermocouples c. liquid in glass thermometers d. filled
system thermometers: c
Question: The difference between the actual value of the measured variable and the set point is a
Correct Answer: Select one: a. disturbance b. composition c. deviation d. divination: c
Question: This type of thermostat is equipped with an open-contact switch or a snap switch
Correct Answer: Select one: a. on-off control b. two position c. modulating d. multipositon: a
Question: It is common for _________ to be attached to a pen mechanism of a chart recorder
Correct Answer: Select one: a. helical and spiral capillary tubes b. helical and spiral bourdon tubes c.
helical and spiral dampeners d. helical and spiral pig tails: b
Question: A two-terminal variable resistor used for varying current in a circuit is known as a
Correct Answer: Select one: a. potentiometer b. rheostat c. thermistor d. photoresistor: b
Question: The _________ network connects numerous controllers with the HMI consoles
Correct Answer: Select one: a. CPU b. DCS c. PCS d. ABB: b (distributed control system)
Question: For programming a HMI you must
Correct Answer: Select one: a. add a card to the HMI b. reconfigure the hard drive c. manually restart the
HMI d. plug a laptop into the HMI: d
Question: This method of flow measurement consists of a length of pipe in which the cross sectional area
converges to a minimum, then diverges to the original pipe size
Correct Answer: Select one: a. pilot tube b. venturi tube c. flow nozzle d. orifice plate: b
Question: The atmospheric gas mixture has a mass that exerts a pressure of approximately _________ on
the earth■s surface at sea level
Correct Answer: Select one: a. 99.3 b. 101.3 c. 103.1 d. 100.3: b
Question: This type of control system responds to changes in conditions regardless of whether an operator
is present
Correct Answer: Select one: a. open loop b. variable loop c. feedback loop d. closed loop: d
,Question: These can be either normally closed or normally open
Correct Answer: Select one: a. stepper valves b. drive valves c. modulating valves d. solenoid valves: d
Question: HMIs restrict operator access to
Correct Answer: Select one: a. visual/search interaction only b. start-stop operating parameters c. less
critical operating parameters d. only critical operating parameters: c
Question: In this type of control mode the control output signal is set by the human operator
Correct Answer: Select one: a. manual mode b. automatic mode with local set point c. automatic mode
with remote set point d. automatic/hand mode: a
Question: The metal bellows type and the piston type are the two types of
Correct Answer: Select one: a. electric damper operators b. pneumatic damper operators c. hydraulic
damper operators d. pilot damper operators: b
Question: The mechanism basic to all pneumatic transmitters is the
Correct Answer: Select one: a. flapper and nozzle b. nozzle and relay c. flapper and relay d. flapper and
bar: a
Question: A _________ is a device that controls large amounts of energy with small amounts of energy
Correct Answer: Select one: a. delay b. relay c. micro switch d. controller: b
Question: In this type of control mode the set point is determined locally by a human operator
Correct Answer: Select one: a. manual mode b. automatic mode with local set point c. automatic mode
with remote set point d. automatic/hand mode: b
Question: HMI is an acronym for
Correct Answer: Select one: a. human machine interaction b. human micro-processing interface c. human
machine internet d. human machine interface: d
Question: In this type of detection, the presence of the process material is detected at predetermined levels
Correct Answer: Select one: a. continuous b. single point c. uninterrupted d. sensor: b
Question: A _________ is a device that converts one form of energy into another form of energy
Correct Answer: Select one: a. transducer b. converter c. inverter d. transponder: a
Question: When the _________ and _________ are at different temperatures, the thermocouple produces a
voltage
Correct Answer: Select one: a. measuring junction / fixed junction b. measuring junction / reference
junction c. sensing junction / reference junction d. sensing junction / fixed junction: b
Question: Variable voltage signals are useful for transmitting signals
Correct Answer: Select one: a. long distances b. short distances c. near adjacent conductors d. near
flammable materials: b
Question: This measures the relative humidity of air in a room or in an air duct
Correct Answer: Select one: a. humidiscope b. humidistar c. humidistat d. humidiprobe: c
Question: PLC■s designed to be used as primary burner safeguard systems require the following
,Correct Answer: Select one: a. all control devices must fail-safe b. all listed answers c. BNS system and
program must be designed by a competent person d. must have a hard-wired watchdog timer: b
Question: This can be linked to the plant management computers, which calculate overall plant costs and
efficiencies
Correct Answer: Select one: a. the programmable computer network b. the central computer network c. the
control computer network d. the operations computer network: c
Question: Reset action, resets or returns the process variable to set point whenever error occurs in this type
of controller
Correct Answer: Select one: a. proportional b. proportional plus integral c. multi-position d. proportional
plus integral plus derivative: b
Question: The differential pressure transmitter can be used for _________ and _________ measurement
Correct Answer: Select one: a. temperature / flow b. temperature / level c. level / flow d. pressure / level: c
Question: Low pressure controllers measure and control low pressure or vacuums, measured in
Correct Answer: Select one: a. mm of light oil b. kN or mm of mercury c. mm of water d. kPa or mm of
mercury: c
Question: Programs that need occasional modifications are stored in
Correct Answer: Select one: a. EPROM b. ROM c. RAM d. EPRAM: a
Question: Hard controls on a HMI communicate with the PLC as_________ if they are not hardwired
Correct Answer: Select one: a. timer codes b. discrete or analog inputs c. field transmitters d. contact
inputs: b
Question: This is a metal sheath used to house temperature sensors
Correct Answer: Select one: a. thermometer b. thermosheild c. thermoelement d. thermowell: d
Question: Discrete digital signals are a type of
Correct Answer: Select one: a. current signal b. resistor signal c. voltage signal d. fibre optic signal: c
Question: The most common form of _________ transmission involves transmitting light along a cable
Correct Answer: Select one: a. wireless signal b. electrical signal c. pneumatic signal d. fibre optic signal:
d
Question: A pigtail _________ maintains a water seal between the steam in a boiler and the bourdon tube
in a pressure gauge
Correct Answer: Select one: a. siphon b. diaphragm c. bellows d. dampener: a
Question: This part of a control system network contains simple devices such as switches, pushbuttons, and
proximity sensors
Correct Answer: Select one: a. device bus b. field bus c. sensor bus d. smart bus: c
Question: Larger, more complex PLC■s tend to be
Correct Answer: Select one: a. modular b. monolithic c. CPU■s d. field transmitters: a
, Question: A _________ thermostat operates like an on-off type, however it has two or more switches that
operate in sequence
Correct Answer: Select one: a. modulating b. multi-position c. two position d. aquastat: b
Question: The _________ is the part of a control valve that moves the valve stem
Correct Answer: Select one: a. inlet b. bonnet c. actuator d. yoke: c
Question: Manual control is also known as
Correct Answer: Select one: a. operator control b. human contol c. forced control d. hand control: d
Question: This component of an electrical control system interrupts or diverts electrical power supply
Correct Answer: Select one: a. transmitter b. switch c. controller d. actuator: b
Question: These may receive process information via discrete voltage signals, through contact closure
inputs
Correct Answer: Select one: a. control system managers b. control system permissives c. control system
transmitters d. control system computers: d
Question: The control systems dedicated to combustion safety and operator assistance in the starting and
stopping of fuel preparation and burning equipment and for preventing misoperation of and damage to fuel
preparation and burning equipment, is the definition for
Correct Answer: Select one: a. burner management systems b. fuel management systems c. burner control
systems d. fuel control systems: a
Question: A __________ analyzes the components of a gaseous mixture or a liquid in vapor form
Correct Answer: Select one: a. chromanalyzer b. chromadectector c. chromatograph d. chromalogic: c
Question: A _________ is a change in a process that cannot be predicted
Correct Answer: Select one: a. process deviation b. process composition c. process offset d. process
disturbance: d
Question: The variable area meter is also known as a
Correct Answer: Select one: a. nutating disc meter b. rotometer c. velocometer d. Doppler meter: b
Question: This part of a control loop is used to adjust the manipulated variable
Correct Answer: Select one: a. final control element b. transmitter c. indicator d. controller: a
Question: This type of controller produces infinitely variable control output signals based on error between
process variables and set points
Correct Answer: Select one: a. non-modulating b. modulating c. non-cascading d. cascading: b
Question: These are typically variable current or variable voltage signals from pressure, level, temperature,
flow or other transmitters
Correct Answer: Select one: a. discrete inputs b. analog inputs c. pneumatic inputs d. hydraulic inputs: b
Question: A _________ is a central computer that holds a collection of data and software programs
Correct Answer: Select one: a. controller b. workstation c. server d. DCS: c
Question: These are used as electromechanical actuators in industrial control applications
