Home Forums General Discussion Technical Questions Scenario based technical question

I know of instances when a car went into the overhead and crashed, the car got stuck in the overhead, car safties applied.
This must be somthing that you are really trying to get the answer you want and won't let it go. That car would not have recovered in that instance, and yes there would be new skivies involved. Use your BS detector. The car would not have lowered if the case was that it slipped traction in the up direction. If it was overspeeding in the up direction most likley it would have tripped the overspeed switch on the governor, top final, both of which is in the safety circuit. 21 is not a highrise.

Ok...If I still remember the jist of this story correctly, there was no slipping traction, or overspeed involved in that particular case...
The whole plot revolved around the fact that the numbers on the floor counting-off display have somehow reset themselves, while the elevator was traveling in the upwards direction and started counting back from the ground floor, when in fact it was already passing a much higher floor...
In this story/legend, the elevator was simply confused at which floor it really was, so if it were a 21 storey building and the counter has reset back to 0 around 15-th floor this would mean that there were only 6 more floors available, while the elevator would somehow "think", that it still has the full 21 floors to go...

At the extreme end of nomal travel in both directions safety circuit stops the car, and will not restart with ELEVATOR tech reseting, regardless of what the PI says.

Thank you..this is the answer I was looking for, as far as this story is concerned.
Obviously an urban legend of sorts...

Your example is not uncommon. I would also suggest don't get caught up on superlatives like 'crashed' as it is incorrect and places a slant on the typical write ups from journo's to paint a picture of a lack of safety in lifts. What happened most likely, is the lift got what we call out of step. This happens sometimes but in NO WAY is the lift now UNSAFE. The lift will then continue in the up direction until in performs a CONTROLLED slow down into the top floor via the emergency terminal stopping. The reason why it 'seems' like it crashes is because the slowdown is done within a certain distance and has to be done quickly.

Thank you uppo72....Is there a building code on how much space there has to be between the elevator cab's roof and and the ceiling of the shaft once the elevator is sitting at the very top floor, or does it vary from building to building?

When your counterweight is fully buffered out there has tp be enough room for the top of the cab not to hit any of the deflector sheaves in the overhead. Every building is different I've had buildings with huge overheads and then none at all.