AR BAS Building Automation
Contractor Exam Questions And
Correct Answers (Verified Answers)
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1.Which protocol is commonly used for communication in building
automation systems?
A. HTTP
B. BACnet
C. FTP
D. SMTP
Rationale: BACnet is the standard protocol designed specifically for
building automation and control networks.
1. What is the main function of a programmable logic controller (PLC) in
a BAS?
A. To supply electrical power
B. To monitor weather conditions
C. To control HVAC, lighting, and other building systems
D. To provide internet connectivity
Rationale: PLCs are used to automate and control mechanical and
electrical systems in buildings.
2. Which sensor type measures occupancy in a room?
A. Temperature sensor
B. Pressure sensor
C. Motion sensor / Occupancy sensor
D. Humidity sensor
Rationale: Occupancy sensors detect movement to determine if a
space is occupied and adjust systems accordingly.
,3. What does the acronym VFD stand for in BAS?
A. Variable Frequency Device
B. Variable Frequency Drive
C. Variable Flow Detector
D. Voltage Flow Drive
Rationale: A VFD adjusts motor speed by varying the frequency of
the electrical supply.
4. Which of the following is an advantage of integrating lighting controls
into BAS?
A. Reduces system reliability
B. Increases energy consumption
C. Optimizes energy usage and occupant comfort
D. Increases maintenance complexity
Rationale: Integrated lighting control allows automated adjustments
based on occupancy, daylight, and schedules.
5. In a building automation system, what is the purpose of a control loop?
A. To provide Wi-Fi
B. To maintain a process variable at a desired setpoint
C. To supply backup power
D. To log security events
Rationale: Control loops continuously monitor and adjust variables
like temperature or pressure to maintain desired conditions.
6. What is the primary function of a thermostat in a BAS?
A. Measure humidity
B. Control lighting levels
C. Regulate temperature
D. Detect motion
Rationale: Thermostats are devices that measure temperature and
control heating/cooling accordingly.
7. Which component converts analog sensor signals into digital signals for
the BAS controller?
A. Actuator
B. Relay
C. Analog-to-digital converter (ADC)
D. Transformer
Rationale: ADCs allow the controller to process sensor signals in
digital form.
, 8. What is the function of an actuator in a BAS?
A. To sense temperature
B. To move or control a device, such as a damper or valve
C. To monitor network traffic
D. To provide data storage
Rationale: Actuators receive control signals and adjust mechanical
devices accordingly.
9. Which BAS component is responsible for sending commands to
actuators based on sensor input?
A. Relay
B. Controller
C. Transformer
D. Sensor
Rationale: Controllers interpret sensor data and generate output
signals to actuators.
10. What is the standard communication protocol used for energy
management systems in buildings?
A. HTTP
B. Modbus
C. FTP
D. SMTP
Rationale: Modbus is widely used for industrial and building energy
management communications.
11. Which type of HVAC control strategy adjusts output based on
outside air temperature?
A. Setpoint control
B. Outdoor reset control
C. Proportional control
D. On/off control
Rationale: Outdoor reset adjusts heating/cooling based on outdoor
temperature for efficiency.
12. What is the purpose of trend logging in BAS?
A. To reset sensors
B. To record historical data for analysis
C. To supply power to devices
D. To encrypt communications
Contractor Exam Questions And
Correct Answers (Verified Answers)
Plus Rationale2026 Q&A| Instant
Download Pdf
1.Which protocol is commonly used for communication in building
automation systems?
A. HTTP
B. BACnet
C. FTP
D. SMTP
Rationale: BACnet is the standard protocol designed specifically for
building automation and control networks.
1. What is the main function of a programmable logic controller (PLC) in
a BAS?
A. To supply electrical power
B. To monitor weather conditions
C. To control HVAC, lighting, and other building systems
D. To provide internet connectivity
Rationale: PLCs are used to automate and control mechanical and
electrical systems in buildings.
2. Which sensor type measures occupancy in a room?
A. Temperature sensor
B. Pressure sensor
C. Motion sensor / Occupancy sensor
D. Humidity sensor
Rationale: Occupancy sensors detect movement to determine if a
space is occupied and adjust systems accordingly.
,3. What does the acronym VFD stand for in BAS?
A. Variable Frequency Device
B. Variable Frequency Drive
C. Variable Flow Detector
D. Voltage Flow Drive
Rationale: A VFD adjusts motor speed by varying the frequency of
the electrical supply.
4. Which of the following is an advantage of integrating lighting controls
into BAS?
A. Reduces system reliability
B. Increases energy consumption
C. Optimizes energy usage and occupant comfort
D. Increases maintenance complexity
Rationale: Integrated lighting control allows automated adjustments
based on occupancy, daylight, and schedules.
5. In a building automation system, what is the purpose of a control loop?
A. To provide Wi-Fi
B. To maintain a process variable at a desired setpoint
C. To supply backup power
D. To log security events
Rationale: Control loops continuously monitor and adjust variables
like temperature or pressure to maintain desired conditions.
6. What is the primary function of a thermostat in a BAS?
A. Measure humidity
B. Control lighting levels
C. Regulate temperature
D. Detect motion
Rationale: Thermostats are devices that measure temperature and
control heating/cooling accordingly.
7. Which component converts analog sensor signals into digital signals for
the BAS controller?
A. Actuator
B. Relay
C. Analog-to-digital converter (ADC)
D. Transformer
Rationale: ADCs allow the controller to process sensor signals in
digital form.
, 8. What is the function of an actuator in a BAS?
A. To sense temperature
B. To move or control a device, such as a damper or valve
C. To monitor network traffic
D. To provide data storage
Rationale: Actuators receive control signals and adjust mechanical
devices accordingly.
9. Which BAS component is responsible for sending commands to
actuators based on sensor input?
A. Relay
B. Controller
C. Transformer
D. Sensor
Rationale: Controllers interpret sensor data and generate output
signals to actuators.
10. What is the standard communication protocol used for energy
management systems in buildings?
A. HTTP
B. Modbus
C. FTP
D. SMTP
Rationale: Modbus is widely used for industrial and building energy
management communications.
11. Which type of HVAC control strategy adjusts output based on
outside air temperature?
A. Setpoint control
B. Outdoor reset control
C. Proportional control
D. On/off control
Rationale: Outdoor reset adjusts heating/cooling based on outdoor
temperature for efficiency.
12. What is the purpose of trend logging in BAS?
A. To reset sensors
B. To record historical data for analysis
C. To supply power to devices
D. To encrypt communications
