Request to Exit, or REX, is a type of sensor commonly used alongside access control systems to automate the opening of doors and expand event sensing capabilities. The REX functions by detecting when there's continuity across the two wires in the REX section of the door cassette, therefore any Normally Open (NO) button, sensor, etc. can be used as a REX.

Most commonly, motion detectors are used on the egress (exiting) side of a door to automatically disengage a lock as someone approaches the door.

REX options are available under the door settings page. To make use of REX settings, you must first enable REX under the hardware section:

REX Door Unlock

As mentioned above, a REX can be used to disengage the lock. To enable this behavior, toggle the REX Unlock Door option. The duration option refers to how long the door will stay unlocked when the REX is engaged.

Door Forced Open Detection

A REX and DPI are required in order to detect Door Forced Open (DFO) events, such as a break-in. This is because a REX allows the system to be aware of valid egress and a card reader allows the system to be aware of valid ingress. If the system detects that the door has opened without a valid card read or REX event, a DFO event is thrown.

In order to detect DFO events, you must enable the Monitor DFO option: