Access Control Power Supplies

An access control power supply turns building power into the low voltage DC that electrified door hardware runs on: electric strikes, magnetic locks, electrified exit devices, card readers and the relays that tie them together. It usually mounts in a steel enclosure near the doors it serves.

Size it to the hardware. Add up what each device draws at its voltage, and allow for inrush: some electrified exit devices draw a short surge when they pull the latch back. Relay and distribution boards split and switch the output between doors. Battery backup keeps the hardware working through a power cut. A fire alarm interface releases locks when the alarm signals, which many locked egress doors must do. Our delayed egress locking guide covers one case. See also electric strikes and magnetic locks.