Use a timer relay such as the Altronix 6062, to be triggered by the panel's Area Armed relay (D8129), to trip a point programmed as a Key Switch Point.
Upon disarming the area, the Area Armed relay will start the timer on the timer relay. At the end of the timer cycle, its contacts change state, tripping the Key Switch Point and arming the area.
Note: Program all points in the area to be re-armed upon as Force Arm Returnable to aviod security voids if the time expires while the area is still in use.
