NEIEP Mechanics Practice Exam

Which safety device is essential for a normal installation of a counterweight weighing more than the car capacity?

1. Mechanical brake

2. Buffer system

3. Counterweight safeties

4. Overload controller

The correct answer is: Counterweight safeties

In the context of elevator systems, when a counterweight weighs more than the car's capacity, the installation of counterweight safeties is crucial. Counterweight safeties are designed to prevent potential hazards that could arise from the counterweight falling or moving uncontrollably. They function as a safety mechanism that can engage and halt the counterweight's descent in the event of an emergency or failure in the system. This safety device ensures that if the system experiences an unexpected failure, such as a cable break or mechanical failure, the counterweight does not pose a risk to the elevator shaft or any individuals nearby. Instead, the counterweight safeties can effectively limit the movement of the counterweight, thereby safeguarding the entire installation. While other choices such as mechanical brakes, buffer systems, and overload controllers play significant roles in overall elevator safety and function, they do not specifically address the unique situation posed by a counterweight that exceeds the car capacity. Mechanical brakes primarily serve to stop the car's motion under normal operation or emergency situations. Buffer systems cushion the elevator's movement at the extreme ends of its travel, and overload controllers detect excess weight in the car to prevent operation. Each serves important purposes, but when it comes to a specifically heavy counterweight scenario