WP6-Brochure-E4 brochure - ELA European Lift Association.

• Hall Call allocation and Double‐Deck lifts
The use of hall call allocation enables the system to assign the number of passengers that is
more likely to match the counterbalancing ratio of the lift, thus minimising the energy used.
This is especially pertinent in low traffic periods, when it is less important that lifts travel at
their maximum capacity.
One solution to improve the traffic handling capabilities of a lift system in very high‐rise
buildings is to use Double‐Deck (DD) lifts. This system consists of two individual cars that travel
together, the upper one serving odd floors and the lower one even floors. Both cars travel
using the same shaft and drive system, saving space and resources.
Figure 3‐24. Double‐Deck lift (source: Schindler)
For DD lifts to work efficiently it is necessary to have a large floor area typically in excess of
2.000 m 2 to ensure a balanced demand and a high level of coincidence for people travelling to
consecutive levels [12].
Modern double‐deck systems use sophisticated controls to ensure that the best deck is
allocated to calls minimising waiting times, travel time and number of stops.
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