ABSA 3B1 Practice Questions With Complete Solutions
469. An oxygen analyzer can also be provided to indicate the
excess oxygen in the flue gas, assisting the operator to control
the excess air and increasing boiler _______.
a. load
b. firing
c. temperature
d. efficiency
d. efficiency
470. Combustion regulation is a function of:
a. Steam drum pressure
b. Fuel flow
c. Air flow
d. Fuel-air ratio
e. Feed water flow
a. Steam drum pressure
471. A pressure modulating control (pressuretrol):
a. Maintains a constant firing rate
b. Will vary fuel and air supply according to steam pressure
c. Cannot be adjusted
d. Can vary fuel and air supply separately
e. Starts and stops the burner at predetermined settings
b. Will vary fuel and air supply according to steam pressure
472. Direct combustion control measures and responds to:
a. Air flow and steam pressure
,b. Air flow and fuel flow
c. Steam pressure only
d. Steam pressure and fuel flow
e. Steam pressure and steam flow
c. Steam pressure only
473. On a coal fired unit using a stoker and obtaining good
combustion efficiency we would probably use:
a. Steam flow-air flow control
b. Fuel flow-air flow control
c. Air flow-fuel flow control
d. Direct control
e. Positioning control
a. Steam flow-air flow control
474. By measuring and comparing the steam and the ________,
it is possible to obtain efficient combustion in a boiler by
maintaining a proper steam to airflow ratio.
a. feedwater
b. fuel
c. airflow
d. drum level
c. airflow
475. In coal fed to furnaces, the airflow is measured and
maintained in a predetermined ratio with the steam flow.
a. True
b. False
a. True
,476. The furnace pressure controller will adjust the boiler
______ dampers to keep the pressure constant at all boiler loads.
a. outlet
b. inlet
c. air
d. burner
a. outlet
477. In a fuel flow-airflow combustion control system, the fuel
and airflows are measured directly and are converted to
_________ signals by means of square root extractors.
a. digital
b. parallel
c. proportional
d. output
c. proportiona
478. In a fuel flow-airflow combustion control system, the fuel
flow signal makes the final adjustment to the ____.
a. feedwater
b. fuel
c. airflow
d. drum level
c. airflow
479. When increasing the firing rate manually it is best to:
a. Increase air flow before fuel flow
b. Increase fuel flow before air flow
c. Increase air and fuel together
, d. It really doesn't matter
e. Decrease fuel flow before increasing air flow
a. Increase air flow before fuel flow
480. Before making adjustments or altering the fuel-air ratio of a
combustion control system, we would:
a. Measure fuel flow
b. Analyze flue gas
c. Increase air flow
d. Decrease firing rate
e. Measure steam flow
b. Analyze flue gas
481. When master controller output goes directly to a fuel valve
and a modulating relay we have:
a. Multi-element control
b. Air flow-fuel flow control
c. Fuel flow-air flow control
d. Steam flow-air flow control
e. Positioning Control
c. Fuel flow-air flow contro
482. In a airflow-fuel flow combustion control, airflow signal
becomes the set point of the ____ controller.
a. feedwater
b. fuel
c. airflow
d. drum level
b. fuel
469. An oxygen analyzer can also be provided to indicate the
excess oxygen in the flue gas, assisting the operator to control
the excess air and increasing boiler _______.
a. load
b. firing
c. temperature
d. efficiency
d. efficiency
470. Combustion regulation is a function of:
a. Steam drum pressure
b. Fuel flow
c. Air flow
d. Fuel-air ratio
e. Feed water flow
a. Steam drum pressure
471. A pressure modulating control (pressuretrol):
a. Maintains a constant firing rate
b. Will vary fuel and air supply according to steam pressure
c. Cannot be adjusted
d. Can vary fuel and air supply separately
e. Starts and stops the burner at predetermined settings
b. Will vary fuel and air supply according to steam pressure
472. Direct combustion control measures and responds to:
a. Air flow and steam pressure
,b. Air flow and fuel flow
c. Steam pressure only
d. Steam pressure and fuel flow
e. Steam pressure and steam flow
c. Steam pressure only
473. On a coal fired unit using a stoker and obtaining good
combustion efficiency we would probably use:
a. Steam flow-air flow control
b. Fuel flow-air flow control
c. Air flow-fuel flow control
d. Direct control
e. Positioning control
a. Steam flow-air flow control
474. By measuring and comparing the steam and the ________,
it is possible to obtain efficient combustion in a boiler by
maintaining a proper steam to airflow ratio.
a. feedwater
b. fuel
c. airflow
d. drum level
c. airflow
475. In coal fed to furnaces, the airflow is measured and
maintained in a predetermined ratio with the steam flow.
a. True
b. False
a. True
,476. The furnace pressure controller will adjust the boiler
______ dampers to keep the pressure constant at all boiler loads.
a. outlet
b. inlet
c. air
d. burner
a. outlet
477. In a fuel flow-airflow combustion control system, the fuel
and airflows are measured directly and are converted to
_________ signals by means of square root extractors.
a. digital
b. parallel
c. proportional
d. output
c. proportiona
478. In a fuel flow-airflow combustion control system, the fuel
flow signal makes the final adjustment to the ____.
a. feedwater
b. fuel
c. airflow
d. drum level
c. airflow
479. When increasing the firing rate manually it is best to:
a. Increase air flow before fuel flow
b. Increase fuel flow before air flow
c. Increase air and fuel together
, d. It really doesn't matter
e. Decrease fuel flow before increasing air flow
a. Increase air flow before fuel flow
480. Before making adjustments or altering the fuel-air ratio of a
combustion control system, we would:
a. Measure fuel flow
b. Analyze flue gas
c. Increase air flow
d. Decrease firing rate
e. Measure steam flow
b. Analyze flue gas
481. When master controller output goes directly to a fuel valve
and a modulating relay we have:
a. Multi-element control
b. Air flow-fuel flow control
c. Fuel flow-air flow control
d. Steam flow-air flow control
e. Positioning Control
c. Fuel flow-air flow contro
482. In a airflow-fuel flow combustion control, airflow signal
becomes the set point of the ____ controller.
a. feedwater
b. fuel
c. airflow
d. drum level
b. fuel
