NEIEP Mechanics Practice Exam

When servicing dumbwaiters, what adjustments must be made to ensure the doors are locked when the car leaves the floor?

1. Lock the doors when the car is no more than 6 inches from the floor

2. Lock the doors when the car is no more than 3 inches from the floor

3. Lock the doors when the car is at the maximum height

4. Lock the doors always at the safety stop

The correct answer is: Lock the doors when the car is no more than 3 inches from the floor

To ensure the doors of a dumbwaiter are locked when the car leaves the floor, it's crucial to implement the proper adjustment that triggers the lock mechanism effectively without risking safety or operational issues. Locking the doors when the car is no more than 3 inches from the floor is correct because this distance provides a fail-safe approach. It ensures that the car is almost at the level where it will either load or unload items, significantly reducing the risk of accidental openings during operation. This short distance offers a balance; it is close enough to make sure that the car is landing within the designated area while also allowing for the alignment of the car to the door at the floor. Furthermore, this approach helps in preventing potential hazards from occurring during the loading or unloading of materials, thereby promoting safety during operation. The other options, while they may allude to locking mechanisms, either do not account for the safety margin needed or suggest activities that could compromise the safe operation of the dumbwaiter. These adjustments are essential for ensuring the equipment functions correctly and safely in everyday use.