Lift readjustment, also called readjusting
The elevator car might ascend or descend slightly during unloading or loading. This happens because the hydraulic system is either strained or relaxed depending on the loading condition. The car is moved automatically to prevent differences of level – between the car’s doorstep and the landing sill - from arising.
The deviation from the tolerance range for the automatic levelling is normally +/- 5 mm.