In this elevator rescue training video, instructor Geoff Davis investigates elevator mechanical design, specifically electro-mechanical elevators. Discover how the counterweight, designed to be heavier than the elevator, prevents falls even in a total system failure. Learn about the mechanics that keep you safe during mechanical lift elevator rescues.

VIDEO TRANSCRIPTION:

The hoist way of an electro-mechanical is going to have a lot more stuff, a lot of moving parts, a lot more moving cables.

You have that counterweight moving up and now behind you, a lot more going on above these than a hydraulic.

The hoist ropes going up to the machine room. On the right. That’s the approach that we’ll go down to the elevator, going back up the a-driven machine room. Ropes going down off the machine down to the elevator.

This is how these things are anchored in the machine room themselves is literally just a piece of metal. The cables coming up through being bolted in.

If you have a complete and total malfunction of every safety system, on an elevator, and it’s going to move freely. Those elevators [are] going to move up, not down because of this counterweights. A counterweight is equal to maximum capacity of the elevator plus 40%.

So, there’s no way we’re ever going to be able to tip that scale to put enough on an elevator to make it fall, because it’s heavier than the counterweight.

 If you open the doors on one and that counterweight is in that back wall right in front of you. You know that that all there has to be all the way up.

On the right is a sheathe break there. If the elevator senses that is moving too fast that sheathe brake will collapse on the sheathe and physically make it not.