Electrified Hardware, Access Control, and Life-Safety Interface
Failure modes first
Electrified hardware is designed around what happens when power fails. Fail safe means unlocked on power loss (typical of maglocks and some egress configurations); fail secure means locked on power loss (typical of most electric strikes and electrified locks). Neither term describes fire performance. Life-safety code requires free egress at all times, so access control may restrict entry but must not trap occupants. Know request-to-exit (REX) devices, door position switches, card readers, controllers, power supplies, and power transfer devices. Delayed egress is a special locking arrangement with a 15-second delay, an alarm, and signage, and it is not permitted in every occupancy.
Traps
Questions reverse fail safe and fail secure, or assume a maglock is acceptable on a fire-rated corridor door without fire alarm release and REX. An electric strike cannot release a deadbolt. A REX sensor is not a substitute for mechanical egress hardware. Power supplies must be listed and sized for continuous load and voltage drop; long runs at 12 VDC lose voltage. Wiegand and OSDP are reader-to-controller protocols, not lock power.
Worked example
A secure records room needs the door locked when power fails, with free egress. A maglock is fail safe (unlocked on loss), so it is the wrong choice. Use a fail-secure electric strike or electrified mortise lock with mechanical key override and inside lever free. Verify the fire alarm interface if the door is rated. Rule of thumb: the egress side stays mechanical; the secure side may be electrified.