A control feature that begins opening the elevator car and landing doors while the car is still decelerating towards a floor within the door zone, reducing the total floor-to-floor journey time and improving passenger throughput.
Full Definition
Pre-opening (also called advance door opening or pre-travel door opening) is a time-saving feature available on elevators equipped with VVVF drives and accurate position encoders. As the car enters the door zone (typically ±150–200 mm of the landing level), the controller initiates the door open command before the car has fully stopped — reducing the time passengers wait for the doors to open once the car levels. EN 81-20 permits pre-opening provided: (1) the car is within the door zone; (2) speed does not exceed 0.3 m/s when the door begins to open; and (3) the landing door interlock is released only when conditions (1) and (2) are both met. This prevents a passenger from stepping through a partially open door into the hoistway before the car has reached the landing. Pre-opening can reduce round trip time (RTT) by 2–5 seconds per stop, which is significant in high-traffic elevator groups. It is a standard feature of modern destination dispatch and group controller programmes.
