Estimated time of arrival (ETA)

A control system that allocates hall calls to the elevator with the lowest Estimated Time of Arrival.

Mode

In Up peak mode, “idle” cars are returned to the Home Floor with a parking call that does not open the elevator doors on arrival. This strategy normally improves uppeak traffic handling. Using this algorithm, elevators are loaded one at a time. This encourages people to fill one elevator rather than partially fill two or more elevators.

In Heavy up peak mode, “idle” cars are returned to the Home Floor with a parking call that opens the elevator doors on arrival. This strategy improves on the Up peak mode for particularly heavy traffic situations when it is advantageous to load more than one elevator at a time. If this is not the case, the mode is normally less efficient than Up peak.

In Down peak mode, the served floors above the Home Floor are divided into sectors, where the number of sectors is equal to the number of elevators. Elevators are dispatched to the sectors in turn. When the elevator has served the down calls in its allocated sector, it is allowed to stop for additional hall calls in its path on the trip back to the Home Floor. This strategy normally improves performance when the predominant traffic flow is in the down direction towards the Home Floor.

In Auto mode, up and down peak detection is used to turn the Up peak and Down peak modes on and off. For uppeak detection, each time the car departs from the Home Floor, the system counts the number of car calls registered. If this is greater than a calculated trigger number, then the uppeak counter is incremented; otherwise, the counter is decremented. To allow for application in different scenarios, the trigger number is a function of the number of floors and number of elevators. When the uppeak counter reaches a threshold, the uppeak mode is turned on. If a second, higher threshold is reached, heavy uppeak mode is turned on.

For down peak detection, the system counts the number of down calls in a round trip. Like uppeak detection, there is a trigger number based on which the down peak counter is incremented or decremented. If the threshold is reached, the down peak mode is turned on. Both up and down peak counters are incremented faster than they are decremented as it is normally better to have the peak mode selected early than late. Mode detection includes hysteresis to avoid the peak mode being turned off during short periods of low traffic demand.

Advanced Settings

Early car announcement can be turned on or off. When turned on, it is assumed that as soon as a passenger places a hall call, the allocated car is “announced” with a gong and/or light. This can assist in passenger loading, which can be modelled in Elevate by reducing Passenger Loading Time. However, when a call is announced, it can no longer be re-allocated. This generally impairs the performance of the dispatcher.

Load bypass can be turned on or off. When turned on, this feature will prevent hall calls from being allocated to full cars. The load bypass threshold determines how full a car is before load bypass comes into operation.

Coincident call bonus reduces the calculated ETA for a hall call if the elevator is already stopping at the same floor for a car call. This normally reduces the overall number of stops made by the elevator and consequently improves performance.

Number of cars loading simultaneously during uppeak allows you to specify the maximum number of elevators you want to load at the same time during an uppeak, from the Home Floor. This option only takes effect if you are using the Up peak mode. Normally, a system would only load one car at a time. However, in heavy traffic situations, it can be advantageous to load more. The based on people counter at home floor option assumes that there is a people counting device at the Home Floor. This device determines how many people are waiting and uses this information to decide how many elevators to load simultaneously.