CML Security Systems Installation & Maintenance 2 — Questions and Answers
Question 1: When installing a door contact sensor for an alarm system, where should the magnet component be mounted?
- On the door frame
- On the moving door or window (Correct answer)
- On the wall adjacent to the door
- On the floor threshold
Correct answer: On the moving door or window
The magnet is mounted on the moving door or window while the sensor switch is mounted on the fixed frame, so movement separates them and triggers the alarm.
Question 2: A customer reports their access control card reader beeps twice but does not unlock the door. What is the most likely cause?
- Card is demagnetized
- The credential is valid but access is denied by schedule or permission settings (Correct answer)
- The reader needs to be replaced
- Power supply failure
Correct answer: The credential is valid but access is denied by schedule or permission settings
Two beeps on most systems indicate the card was read successfully but access was denied due to time schedule restrictions or insufficient access level permissions.
Question 3: Which wire gauge is most commonly specified for low-voltage alarm system wiring runs up to 500 feet?
- 22 AWG (Correct answer)
- 14 AWG
- 10 AWG
- 6 AWG
Correct answer: 22 AWG
22 AWG is the industry standard for most alarm sensor wiring over typical residential and commercial distances up to 500 feet.
Question 4: What does EOL (End of Line) resistor supervision in an alarm loop detect?
- Power surges on the panel
- Both open circuit (cut wire) and short circuit (wire bridging) tamper conditions (Correct answer)
- Battery backup status
- Motion sensor range limits
Correct answer: Both open circuit (cut wire) and short circuit (wire bridging) tamper conditions
EOL resistors allow the panel to monitor the loop for both opens (tamper/break) and shorts (defeat attempt) by measuring the resistance value of the circuit.
Question 5: A glass break detector is being installed in a room with heavy drapes. Where should it be positioned for best performance?
- Behind the drapes, directly on the glass
- On the ceiling or wall with a clear acoustic path to the protected glass (Correct answer)
- On the floor pointing upward
- Inside the window frame
Correct answer: On the ceiling or wall with a clear acoustic path to the protected glass
Glass break detectors rely on acoustic sensing and must have an unobstructed sound path to the glass; drapes and other soft materials absorb the high-frequency break sound.
Question 6: When programming a new credential in an access control system, which data field uniquely identifies each cardholder record?
- Card format
- Facility code only
- Card number or badge ID (Correct answer)
- Access group assignment
Correct answer: Card number or badge ID
The card number or badge ID is the unique identifier for each cardholder, while facility code and format apply to all cards in a site.
Question 7: A magnetic lock (magloc) fails to release when the exit button is pressed. What is the first component to test?
- The power supply voltage
- The maglock holding force
- The output relay wiring from the access control panel or timer relay (Correct answer)
- The door frame alignment
Correct answer: The output relay wiring from the access control panel or timer relay
The exit button signals the panel or relay to cut power to the maglock; a failed output relay or broken wiring in that circuit is the most common cause of release failure.
CML Security Systems Installation & Maintenance 2
When installing a door contact sensor for an alarm system, where should the magnet component be mounted?