Design and Functions
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Figure 20: Behavior of the upper limit switches
10.3.4
Unintended Car Movement (UCM)
Supervision on UCM is enabled if the car is in stands still in the re-levelling door zone of a floor and doors are
open (not voltage on DCS-L). If, after this, the car leaves the re-levelling door zone of the floor where it stopped
last time or if the speed exceeds 0.3 m/s with doors still open, UCM trips and OC, NOC and SGC are open.
The contacts are kept open even after stand still. This state is stored in a non-volatile way: The contacts will also
be open after power cycle. This state is cleared by manual reset by RESET-Button.
Supervision on UCM is disabled if doors are closed (SC-Voltage present on DCS-L. In case of overlapping door
zones, Safe Box always supervises the zone of the floor closest to the position where car stopped and doors
opened.
10.3.5
Door bridging
When sending the door bridging command „enable levelling“, the lift control must always
exclusively indicate the number of the target floor of the actual travel.
When sending the door bridging command „enable re-levelling“, the lift control must always
exclusively indicate the number of the floor where the cabin stops at the moment.
Indication of another floor number is prohibited.
Open
Closed
inspection limit switch, temp. ref. position set
upper temp.
ref. position
Pos.
Open
Closed
final limit switch, temp. ref. position set
Closed
limit switches, temp. ref. position not set yet
Upper limit switches behavior
Open
Open
Closed
highest
floor
Closed
Open
Pos.
final limit switch
inspection limit switch
Normal and
adjustment mode
Teach mode
Offset of final limit switch [30 … 100 mm]
Offset inspection limit switch [1300 … 10000 mm]
