You need to record the period for which the car’s doors remain open at each floor. Elevator passengers typically can exit a car in two or three seconds, and can enter a car in about four seconds. Doors that remain open for much longer than this only slow down service. Also important in this exercise is the performance of the door reversing device. When the doors are blocked, they should open again immediately, and then attempt to close again right away. Again, any delays only reduce service. Once the doors are closed, the car should move away immediately.
When measuring the speed with which a car moves from floor to floor, managers must consider the type of hoisting mechanism, and its horsepower, employed by the elevator. A geared elevator, which typically moves at speeds up to 400 feet per minute, should be able to travel the height of ten floors in five or six seconds. Higher speed gearless elevators, which can move 500 feet per minute or faster, can cover the same ten-floor span in four or five seconds. Conversely, slower hydraulic elevators, which typically are limited to speeds of 150 feet per minute, take up to eight seconds to travel the ten-floor distance.
