Low Voltage Tech Exam Questions & Answers 2026 (11–20)

Question 1

What is the function of an access control panel (also called an access controller)?

TheoryPractice · Accepted Answer

To process credential data and make access decisions. The access control panel (controller) is the brain of the system. It receives credential data from readers, compares it to its database, and makes a grant or deny decision, then sends the appropriate signal to the door hardware.

Question 2

In biometric systems, what does the term 'False Acceptance Rate' (FAR) measure?

TheoryPractice · Accepted Answer

The percentage of unauthorized users incorrectly granted access. FAR (False Acceptance Rate) is the frequency at which an unauthorized person is incorrectly accepted by the biometric system. A lower FAR means higher security. It is paired with FRR (False Rejection Rate), which measures how often authorized users are denied.

Question 3

Which biometric modality is generally considered the most accurate and difficult to spoof?

TheoryPractice · Accepted Answer

Iris recognition. Iris recognition has one of the highest accuracy rates among biometric modalities due to the unique and stable pattern of the iris. It is also difficult to spoof compared to fingerprints or facial recognition.

Question 4

In a standard 26-bit Wiegand card format, how many bits are allocated to the card number?

TheoryPractice · Accepted Answer

16 bits. In the 26-bit Wiegand format, 16 bits are used for the card number, 8 bits for the facility code, and 2 bits for parity. The 16-bit card number allows for card numbers ranging from 0 to 65,535.

Question 5

A magnetic lock (maglocks) releases when power is removed. What is the typical holding force of a standard single-door maglock?

TheoryPractice · Accepted Answer

1,200 lb (approximately 545 kg). A standard single-door electromagnetic lock has a holding force of approximately 1,200 lb (545 kg). Double-door versions and higher-security units can achieve higher holding forces, while lighter-duty locks may hold less.

Question 6

Which hardware component monitors whether a door is physically open or closed and reports that status to the access control panel?

TheoryPractice · Accepted Answer

Door position switch (DPS). A door position switch (DPS), typically a magnetic contact, monitors the physical open/closed state of the door and reports it to the controller. This allows detection of forced entry or doors held open too long.

Question 7

What is the purpose of a Request-to-Exit (REX) device in an access control system?

TheoryPractice · Accepted Answer

To signal the controller that someone legitimately wants to exit, suppressing a door-forced alarm. A REX device (motion sensor, push button, or bar) detects legitimate egress and tells the controller to suppress the door-forced alarm and/or unlock the door for exit. Without it, the system would trigger an alarm every time someone exits.

Question 8

Most access control panels and door hardware operate on which voltage?

TheoryPractice · Accepted Answer

12 VDC or 24 VDC. Access control panels and most door hardware (strikes, maglock, readers) are designed to operate on 12 VDC or 24 VDC supplied by a power supply with battery backup. This low-voltage DC design keeps installers under low-voltage licensing requirements.

Question 9

In access control software, an 'access level' defines:

TheoryPractice · Accepted Answer

Which doors a credential holder can access and during what time periods. An access level (also called an access group or access profile) combines a list of doors with time schedules and assigns this combination to credential holders. It answers: 'Who can get into which doors and when?'

Question 10

What function in access control software allows a credential to unlock a door for a set period of time, after which normal time-schedule restrictions resume?

TheoryPractice · Accepted Answer

Temporary access override (extended grant). A temporary access override or extended grant allows a manager to grant a credential holder temporary access beyond normal schedule restrictions for a defined period, after which normal rules automatically resume.

Low Voltage Tech Exam Questions & Answers 2026 (11–20)

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