In one of the PPD practice exams (form 1) there’s a case study question asking what type of an elevator would be the best choice for a 3 story library building, the requirement is for the elevator to be quiet in operation
The answer options consist of several types of hydraulic elevator types, geared traction elevator and gearless traction elevator… The correct answer is a gearless traction elevator. But wouldn’t this be an overkill? Gearless traction elevators are expensive and mostly used in high rise applications?
Hello @Kumiwicky and welcome to the ARE Community!
Can you please provide the question number and which practice exam you are referring to?
(do not post a screenshot)
@coachlizschneider do you mind helping our new user?
It’s question 107 - Form 1
@kumiwicky Thank you for the question. While gearless traction machines are typically chosen for applications where the rise is 250ft or more they are considered to be more efficient, quieter in operation, require less maintenance, and have a longer life than other elevators. In this question, because you are specifically looking for a machine that is quiet in operation, the gearless traction elevator will be your best choice.
If you were choosing an elevator based off of the height of the building, you may go with the hydraulic. However, the noise from the pump and motor of the hydraulic elevator can be very disturbing.
You can read more about the pros and cons of the different elevator types in Mechanical and Electrical Equipment for Buildings Chapter 31 and 32.