Driver, I followed that link and there several differences with the two scenarios. That car didn't go up before it fell down. The machinery (overhead drum) and the supporting members all came tumbling down. They said 500 tons, however even a tandem geared Otis drum would likely top out at about 5 tons, so weight is off a tad. Still, the scenario that you started with had some unique requirements and that was what I went by. Broke Sheave has some good points and is correct with his assessment. Buffers are the items that retard the elevator and counterweight at the extreme ends of travel and are checked regularly for proper operation. However, slower cars (under 200 fpm) have springs and these wouldn't help a lot if you had enough rise to gain momentum. Also, buffers are rated for speed and capacity. Obviously, rated speed would have been exceeded. If you have occupiable space below the elevator shaft, you would have to have counterweight safeties as well as car safeties, and that would have stopped the upward motion of the car by stopping the downward motion of the cwt. In late model elevators, you have rope brakes and sheave brakes that work independently of the safeties and stop the upward movement of the car. You also have UIM (un-intended motion) circuitry on later model elevators. Like I said earlier, If God has it in for you, it's gonna get messy.
