Harbour Centre elevator stops in express shaft zone which has no doors

Incident Investigation

Harbour Centre elevator stops in express shaft zone which has no doors

October 22, 2019

Elevating Devices

Reference Number:

II-748985-2018 (#8737)

Elevator #17 at the Harbour Centre stopped in the express zone, the express zone is an area in the elevator shaft which has no landing doors for those floors. After stopping, the elevator was approximately 200 ft above the ground floor and the car door opened with several passengers inside.

Site, system and components

  • An elevator controller (Photos 1 and 7) is where all the electronic components that control the operation of the elevator are housed. The controller has an inner compartment (Photo 1) for components that are more sensitive to heat/electrical noise. The inner compartment has a cooling fan at the top (Photo 2) which draws cool air from the bottom through all the components. The inner compartment cabinet door must be closed in order for the cooling process to function properly.
  • Under normal conditions, an elevator would not stop in the express zone because no landings are present in that section of shaft. In sections of shaft without landings, the controller requires landings to be programmed into the control system to have the system function properly. These programmed landings in the express zone, that have no landing doors, are called “false floors.”
  • A device called “Car door interlock” (Photo 5) which is attached to the car door, prevents the car door from opening unless it’s within the unlocking zone (zone not more than 18” above or below each landing) for that entrance. When the elevator is stopping at a landing, the interlock is given a signal from the controller to unlock the interlock allowing the car door to open. When the elevator system is functioning properly, the interlock is only given a signal to unlock on landings with hall doors.
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