Definition
A motion sensor or button that signals the system someone is leaving, so the door releases for free egress without triggering an alarm. REX devices are essential for safe, code-compliant access control.
Why this term matters
In access control, terminology typically maps to who can enter, life-safety egress, and how a door behaves during a power outage.
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Related pages
Related terms
Access control An electronic system that controls who can open a door and when, using credentia… Maglock (magnetic lock) An electromagnet that holds a door shut while powered, releasing when power is c… Electric strike A powered door-frame plate that releases the latch to allow entry while keeping … Credential Whatever a person presents to unlock a door — a key fob, proximity card, PIN cod…
Discipline: Access Control