CBCP CBCP Building Automation & Control Systems 2

Question 1

What is the purpose of a 'trend log' in a BAS during commissioning?

Accepted Answer

Logging historical data of control variables over time to verify system performance

Answer

Trend logs capture time-stamped data for sensors and control outputs, allowing commissioning agents to verify proper system behavior over time.

Question 2

A VAV (Variable Air Volume) box fails to modulate during FPT. Which BAS component should the commissioning agent check first?

Accepted Answer

The DDC controller output signal to the VAV actuator

Answer

The DDC controller output signal drives the VAV actuator, so verifying this signal is the logical first diagnostic step.

Question 3

Which ASHRAE guideline specifically addresses the commissioning process for HVAC&R systems?

Accepted Answer

ASHRAE Guideline 0

Answer

ASHRAE Guideline 0 defines the commissioning process for new and existing buildings across all systems.

Question 4

What does the term 'sequence of operations' refer to in a BAS?

Accepted Answer

A written description of how control systems respond to various inputs and conditions

Answer

The sequence of operations is the narrative description of how the BAS controls equipment under various conditions and modes.

Question 5

An AHU economizer damper is found fully closed during a 40°F outdoor air temperature condition when free cooling should be available. Which BAS parameter should be reviewed?

Accepted Answer

Economizer changeover (enable) setpoint

Answer

The economizer changeover setpoint determines the outdoor air temperature or enthalpy threshold at which economizer mode is enabled.

CBCP - Certified Building Commissioning Professional Practice Test

CBCP - Certified Building Commissioning Professional Practice Test

CBCP CBCP Building Automation & Control Systems 2