Low Voltage Tech practice questions and answers 2026. Tap an option to test yourself — you'll see the correct answer and a plain-English explanation for every question. Free, no login.
Q1What is the primary purpose of an access control system?
✓ Correct answer: C. To restrict entry to authorized individuals while denying access to unauthorized persons
Access control systems are designed to allow only authorized individuals to enter specific areas while keeping out unauthorized persons. This protects assets, personnel, and sensitive information.
Topic: Access Control
Q2Which type of credential stores data on a microchip embedded in the card?
✓ Correct answer: A. Smart card
Smart cards contain an embedded microchip that stores and processes data. Unlike magnetic stripe or barcode cards, smart cards can hold more data and support cryptographic operations for enhanced security.
Topic: Access Control
Q3A proximity card reader typically operates at which frequency?
✓ Correct answer: B. 125 kHz
Traditional proximity cards operate at 125 kHz (low frequency). This distinguishes them from high-frequency smart cards (13.56 MHz) used in more modern contactless systems.
Topic: Access Control
Q4Which of the following is an example of a biometric credential?
✓ Correct answer: D. Fingerprint scan
Biometric credentials are based on unique physical or behavioral characteristics of an individual, such as fingerprints, iris patterns, or facial recognition. PINs, cards, and key fobs are not biometrics.
Topic: Access Control
Q5In access control terminology, what does 'authentication' refer to?
✓ Correct answer: A. Verifying that a person is who they claim to be
Authentication is the process of verifying identity—confirming that the person presenting credentials is indeed who they claim to be. Authorization (granting access) is a separate step that follows authentication.
Topic: Access Control
Q6An electric strike holds the door closed when de-energized and releases when energized. This configuration is known as:
✓ Correct answer: B. Fail-safe
Fail-safe (also called fail-open) means the lock releases when power is lost, allowing free egress—important for life-safety reasons. Fail-secure means the lock remains locked when power is removed.
Topic: Access Control
Q7What device is used to prevent 'tailgating' (piggybacking) at a secured entrance?
✓ Correct answer: C. Mantrap (or airlock vestibule)
A mantrap (security vestibule/airlock) uses two interlocked doors so only one person can enter at a time, preventing tailgating. The second door will not open until the first closes and the individual is verified.
Topic: Access Control
Q8The three factors of authentication are 'something you know,' 'something you have,' and:
✓ Correct answer: D. Something you are
The three classic authentication factors are: (1) something you know (PIN, password), (2) something you have (card, token), and (3) something you are (biometric characteristic). Multi-factor authentication uses two or more of these.
Topic: Access Control
Q9What wire gauge is commonly used for access control reader wiring runs under 500 feet?
✓ Correct answer: A. 22 AWG
22 AWG (American Wire Gauge) multi-conductor cable is the standard for access control reader data and power runs up to approximately 500 feet. Heavier gauges (lower AWG numbers) are used for longer runs or higher current loads.
Topic: Access Control
Q10What does 'HID' stand for in the access control industry?
✓ Correct answer: B. HID Global (formerly Hughes Identification Devices)
HID stands for HID Global, originally Hughes Identification Devices. HID is one of the leading manufacturers of access control credentials, readers, and related technology.
Topic: Access Control
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