NEIEP Mechanics Practice Exam

What is the result when traction is lost between the hoist ropes and the machine driver upon counterweight landing?

1. The elevator car is pulled into the overhead

2. The elevator car stops immediately

3. The counterweight is held in the air

4. The hoist ropes are released

The correct answer is: The elevator car is pulled into the overhead

When traction is lost between the hoist ropes and the machine driver during a counterweight landing, the result is that the elevator car is pulled into the overhead. This phenomenon occurs because, without the necessary friction or grip on the machine driver, the hoist ropes can no longer effectively transmit the force needed to balance the weight of the elevator car and its load. In a functioning elevator system, the counterweight is designed to offset the weight of the car, allowing smooth movement. However, when traction is lost, the counterweight may descend freely while the car itself gets pulled upward due to the imbalance. This can lead to a potentially dangerous situation where the car is propelled into the overhead space above, especially if it is not properly secured or if safety devices are not operational. Other options do not accurately describe this scenario: the elevator car stopping immediately would imply that there is still some form of traction or braking effect; the counterweight being held in the air suggests a static condition, which is not the case when traction is lost; and the hoist ropes being released would imply a total failure which would not create the same dynamics at play in this situation. Hence, understanding the mechanical principles at work and the interaction between components is crucial in recognizing why the