If you have a 3500 lb. car rated at 4000 lbs. capacity, how much should the counterweight assembly weigh for a normal 40% installation?

In a typical traction elevator system, the counterweight is designed to balance the weight of the car and provide efficient operation. The counterweight should generally be set to about the same weight as the car, but for a normal installation, it is common to have it weigh approximately 40% more than the actual car weight.

To find the appropriate counterweight for a car rated at 4000 lbs with a weight of 3500 lbs, we take 40% of the car capacity. Calculating 40% of 4000 lbs yields 1600 lbs. When you add this to the weight of the car (3500 lbs), the counterweight needs to be 3500 lbs + 1600 lbs, which equals 5100 lbs.

Thus, the correct answer reflects this calculation, ensuring that the counterweight is balanced adequately to promote smooth operation and safety within the elevator system.