Elevator Mechanic Practice Exam

What is the likely cause if a car loaded with 125% sinks?

1. Electrical fault

2. Hydraulic leak

3. Slipping through the brake

4. Worn-out cable

The correct answer is: Slipping through the brake

When a car loaded with 125% of its capacity sinks, the most probable cause is a hydraulic leak. This situation indicates that the lift system is unable to support the weight due to a loss of hydraulic fluid, which is critical for maintaining the necessary pressure to keep the car elevated. If there were a hydraulic leak, it would result in decreased pressure in the hydraulic system, leading to the car's inability to hold its position under an excess load. This is particularly relevant in hydraulic elevator systems, where lift and lowering are controlled by the hydraulic fluid's pressure. While slipping through the brake may cause the car to descend unexpectedly, it would not specifically cause a car loaded over its limit to sink in a way that is consistent with the behavior described in the question. A worn-out cable could lead to other issues but would generally not result in the immediate sinking of an overloaded car. Lastly, electrical faults typically affect functions unrelated to physical weight-bearing capacities.