Which function keeps a door unlocked for a preset duration after authentication?

Which function keeps a door unlocked for a preset duration after authentication?

• A. Momentary unlock
• B. Constant unlock
• C. Permanent access
• D. Auto unlock on schedule

Answer: (A)

When a credential is verified, the door is released only for a short, predefined period—that’s the momentary unlock. It’s controlled by a timer on the access control relay, so after the person authenticates, the lock energizes briefly and then returns to the locked state. This gives convenient entry while preserving security, because the door can’t stay open indefinitely. Other options don’t fit because they describe different behaviors: a constant unlock would keep the door open forever once authenticated, a permanent access implies ongoing unrestricted entry, and auto unlock on schedule would open at set times regardless of who is present or authenticated.

When a credential is verified, the door is released only for a short, predefined period—that’s the momentary unlock. It’s controlled by a timer on the access control relay, so after the person authenticates, the lock energizes briefly and then returns to the locked state. This gives convenient entry while preserving security, because the door can’t stay open indefinitely.

Other options don’t fit because they describe different behaviors: a constant unlock would keep the door open forever once authenticated, a permanent access implies ongoing unrestricted entry, and auto unlock on schedule would open at set times regardless of who is present or authenticated.