Combplate teeth must be set to ensure they are below the what surface?

Combplate teeth must be set to ensure they are below the upper surface of the elevator landing. This is crucial for safe and efficient operation. By positioning the combplate teeth below the upper surface, it facilitates smooth engagement and disengagement of the elevator car with the combplate during door operation. This design helps to prevent potential accidents or malfunctions, such as misalignment when doors close, which could lead to safety hazards for passengers entering or exiting the elevator. Ensuring the combplate teeth are appropriately set below the upper surface also aids in reducing wear on both the teeth and the elevator landing, extending the lifespan of the components involved.