NEIEP Mechanics Practice Exam

What type of elevator control passes up hall calls in the down direction and down hall calls in the up direction?

1. Selective collective control

2. Automatic collective control

3. Simple collective control

4. Single selective control

The correct answer is: Selective collective control

The type of elevator control that passes up hall calls in the down direction and down hall calls in the up direction is known as selective collective control. This system allows the elevator to efficiently manage multiple calls by optimizing its travel path. When a passenger calls an elevator from a floor, the selective collective control assesses the direction of travel and any existing calls. If the elevator is traveling downward and receives a hall call for a lower floor, it will continue to stop at hall calls in the upward direction before handling any calls for a lower level, thus minimizing travel time and enhancing efficiency. This control method is particularly advantageous in buildings with heavy traffic because it can respond dynamically to calls and adjust its route accordingly, often improving overall service time for users. In contrast, the other types of controls—automatic collective, simple collective, and single selective—operate differently and do not feature the same mechanism of selectively passing floor requests based on the direction of travel. For example, automatic collective control stops only at floors where it has received a call, which does not provide the flexibility of passing calls in the other direction.