CET CET Roping & Counterweight Systems

Question 1

What is the standard minimum number of hoist ropes required for a traction elevator under ASME A17.1?

Accepted Answer

3

Answer

1

Answer

2

Answer

4

Question 2

What is the purpose of the counterweight in a traction elevator system?

Accepted Answer

Offsets the weight of the car and a portion of the rated load to reduce motor energy consumption

Answer

Increases the traction between ropes and drive sheave

Answer

Provides emergency braking if the motor fails

Answer

Stores energy for the door reopening system

Question 3

What percentage of rated load is typically added to the car weight when calculating counterweight mass?

Accepted Answer

40–50%

Answer

25%

Answer

75%

Answer

100%

Question 4

In a 1:1 roping arrangement, how does the rope travel distance compare to car travel distance?

Accepted Answer

Rope and car travel the same distance

Answer

Rope travels half the distance of the car

Answer

Rope travels twice the distance of the car

Answer

Rope travels four times the distance of the car

Question 5

What is the advantage of a 2:1 roping arrangement compared to a 1:1 arrangement?

Accepted Answer

Greater mechanical advantage allowing a smaller motor to lift heavier loads

Answer

Higher car speed for the same motor speed

Answer

Simpler rope installation with fewer sheaves

Answer

Higher traction between rope and sheave

Question 6

What is the minimum design factor (safety factor) required for elevator hoist ropes under ASME A17.1?

Accepted Answer

7.6

Answer

4

Answer

10

Answer

12