«Elevator companies provide false, misleading and incomplete information about the planning and performance of groups of elevators. They ignore the inherent relativity of group characteristics, i.e. do not apply this knowledge to optimize group planning nor to improve the performance and efficiency of group controls. Consequently the planning and installation of inefficient groups continues.»

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The inherent relativity of group characteristics enable the exact planning of group configurations and the optimal performance of groups. Regrettably, this also implies that virtually all existing groups are inefficient, because contract loads are too high and numbers of cars too low. They waste energy, time of passengers, building space and reduce numbers of floors served. For optimal performance, compliance with the laws of nature i.e. the inherent relativity of group characteristics, is essential because it enables the optimal balance of the interdependencies, which determine optimal group performance.

This website and book have provided several examples of the existence of optimal group performance and the feasibility of optimal group planning. In spite of the undeniable evidence of the inherent relativity of group characteristics and optimal performance, elevator companies continue to promote 1600 KG contract loads and empirical planning of groups as was usual in the past for traditional groups. Moreover, promotion of proprietary destination controls, which ignore the inherent relativity of group characteristics, continues. These practices imply that elevator companies pretend control of car operations is irrelevant, alternatively that the optimal planning and performance of groups is impossible.

During the last two years, the author designed and tested a mathematical model, which enable round trip time calculations for simultaneous UP and DOWN traffic with variable carloads. These methods facilitate group performance calculations for groups with any configuration and any combination of up and down traffic densities. The calculated data reflect the data of traffic simulations. Consequently, stress tests facilitate to define optimal group configurations before traffic simulation for confirmation of the calculated data. Traffic simulation data should at least be slightly better because the calculated data are conservative.

Elevator companies often suggest groups manage traffic in buildings. These claims are absurd.
Traffic conditions are spontaneous and not manageable. Traffic conditions in buildings must guide the planning of groups, and manage car operations for optimal performance.

2019: Breakthrough for group planning.
Chapter F: “Exact group planning with traffic simulation” and its EXCEL workbooks RSimxx introduce a mathematical model and “stress tests” for group evaluations. This system enables architects the exact planning of groups for required transport capacities and time-dependent service qualities of any group.

Traffic simulation is the ultimate “tool” for the exact planning and evaluation of groups. Regrettably, elevator companies do not use this ability for the systematic planning of groups. It seems to be a common practice to engage in traffic simulation after the planning of group configurations with outdated empirical evaluation methods. These simulations disclose the performance data of groups with inefficient configurations.

Traffic simulation systems are complex i.e. are not available to architects for independent group evaluation and planning. Chapter 10: “Traffic simulation” provides detailed information of traffic simulation systems.

The EXCEL workbooks RSim10 to RSim20 provide architects with simple tools for the exact and independent planning of configurations for Low Rise and High Rise groups. Traffic simulations confirm the calculated service qualities. After installation, recorded data will reconfirm the guaranteed performance data. For more information, please refer to page Introduction.