Building Automation Systems Flashcards
7 cards from real HVAC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Building Automation Systems flashcards as text
Which communication protocol is most commonly used for BAS integration with lighting control systems?
Answer: BACnet
BACnet is the dominant open protocol for BAS integration across HVAC, lighting, and other building systems.
In a BAS, what does a PID controller stand for?
Answer: Proportional-Integral-Derivative
PID stands for Proportional-Integral-Derivative, a feedback control algorithm that minimizes error between setpoint and measured value.
What is the primary function of a supervisory controller in a BAS hierarchy?
Answer: Coordinate multiple field controllers and enforce global strategies
Supervisory controllers coordinate field-level DDC controllers and implement global optimization strategies like demand limiting.
An HVAC technician notices a BAS trend log shows supply air temperature oscillating rapidly around setpoint. What is the most likely cause?
Answer: PID loop with too-high proportional gain
Excessive proportional gain causes hunting or oscillation around setpoint in a PID control loop.
What BACnet object type is used to represent a physical analog input such as a temperature sensor?
Answer: Analog Input
The BACnet Analog Input object type represents a physical analog measurement such as temperature or pressure.
Which topology is most commonly used for BACnet MS/TP field-level networks?
Answer: Daisy-chain (bus)
BACnet MS/TP uses a daisy-chain bus topology where all devices share a single twisted-pair cable segment.
In BAS programming, what is a 'setback' schedule typically used for?
Answer: Relaxing temperature setpoints during unoccupied periods to save energy
Setback schedules relax HVAC setpoints during unoccupied periods, reducing energy consumption while maintaining acceptable conditions.