C7 Testing & Commissioning Procedures 2 — Questions and Answers
Question 1: During commissioning of a fire alarm system, which test verifies that all notification appliances activate within the required decibel threshold?
- Continuity test
- Sound pressure level test (Correct answer)
- Ground fault test
- Insulation resistance test
Correct answer: Sound pressure level test
A sound pressure level test uses a calibrated meter to confirm notification appliances meet the minimum 15 dB above ambient (or 70 dB minimum) per NFPA 72.
Question 2: When commissioning a CCTV system, what is the primary purpose of performing a back-focus adjustment?
- To set the iris aperture for proper exposure
- To ensure the image remains sharp across the zoom range (Correct answer)
- To calibrate the pan-tilt unit speed
- To align the camera housing to true north
Correct answer: To ensure the image remains sharp across the zoom range
Back-focus adjustment aligns the imaging sensor with the lens focal plane so the image stays sharp at both wide and telephoto zoom positions.
Question 3: A C7 contractor is testing an access control door strike. The door fails to unlock when the credential is presented. Which component should be tested first?
- The door closer spring tension
- The power supply output voltage at the strike (Correct answer)
- The card reader antenna frequency
- The door frame alignment
Correct answer: The power supply output voltage at the strike
Verifying supply voltage at the strike confirms whether the fault is in power delivery before checking control logic or credential hardware.
Question 4: What does a time-domain reflectometer (TDR) measure during cable commissioning?
- Signal frequency response along the cable
- Distance to a cable fault or impedance discontinuity (Correct answer)
- Total cable capacitance per foot
- Crosstalk between adjacent pairs
Correct answer: Distance to a cable fault or impedance discontinuity
A TDR sends a pulse down the cable and measures the time for reflections to return, identifying the distance to faults or impedance changes.
Question 5: During commissioning of a nurse call system, which test confirms that a call initiated at a patient station correctly annunciates at the central console?
- End-to-end functional test (Correct answer)
- Isolation transformer test
- Loop resistance test
- Harmonic distortion test
Correct answer: End-to-end functional test
An end-to-end functional test activates each station individually and verifies the correct zone and priority display at the master console.
Question 6: What California code governs the testing and acceptance of fire alarm systems installed under a C7 license?
- California Electrical Code Article 760
- NFPA 72 and the California Building Code Chapter 9 (Correct answer)
- California Mechanical Code Section 904
- Title 24 Part 6 Energy Standards
Correct answer: NFPA 72 and the California Building Code Chapter 9
NFPA 72 (adopted by reference in the California Building Code Chapter 9) provides the testing and acceptance requirements for fire alarm systems.
Question 7: When testing an intrusion detection system, a walk test is performed primarily to verify what?
- Battery backup runtime under full load
- Proper detection coverage and zone assignment of motion sensors (Correct answer)
- Communication latency to the central monitoring station
- Panel firmware version compatibility
Correct answer: Proper detection coverage and zone assignment of motion sensors
A walk test has a technician move through each sensor's detection zone while the panel logs activations, confirming coverage patterns and correct zone labeling.
C7 Testing & Commissioning Procedures 2
During commissioning of a fire alarm system, which test verifies that all notification appliances activate within the required decibel threshold?