If the runby for a 1:1 car hits the CWT buffer 4" below the top landing, how much should the ropes be shortened?

To determine how much the ropes should be shortened when the runby for a 1:1 car hits the counterweight buffer 4 inches below the top landing, it is important to understand the mechanics of elevator systems.

In a 1:1 configuration, the rope move the car and counterweight directly in relation to each other. When the car travels upward, the counterweight travels downward, ideally maintaining balance. The “runby” represents the additional distance the car continues to move after reaching the top landing before it hits the buffer. This is essentially a safety measure to ensure the car does not impact the landing with excessive force.

If the runby hits the buffer 4 inches below the top landing, that means the effective travel of the car needs to be adjusted so that it does not exceed this safe limit. Since the 1:1 system relies on the lengths of the ropes determining the positions of both the car and counterweight, shortening the ropes directly correlates with lowering the top extent of the car's travel.

To ensure that the car now stops appropriately at the landing rather than hitting the buffer below it, the ropes must be shortened by not just the amount of the runby (which is 4 inches) but also by the