What is it?

It is powered but it's not a machine in the sense it's parts are mechanised. The slots do serve a purpose.

Here's another view.
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Attachment 17483

Is it part of the mechanism of an overhead crane in the building it's located in?

No this device is suspended from a ceiling inside a building. It is one of many. This next image may be more illuminating.
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Attachment 17484

A Mercury or Sodium vapour industrial lighting fixture.

It is a light fixture. This light is one of many
and it's purpose is to aid mechanical eyes.
The mechanical eyes "never blink", often to the delight of the watchers watching the watched.
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Back to the 2nd image. I only took three.
Attachment 17485

The panels attached are used to "direct" the light beam.

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It's a light used for lighting movie sets.The movable baffles would allow the light to be directed only where it is required.

Sorry for the delay folks. Scifan has it. In this case - these lights are in a television studio.
Over to the Norse Oracle.

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Here's the next challenge.
This is a watch dial.To solve this challenge you will have to answer two questions. What is this type of dial called? On what kind of watch would you expect to see this type of dial?

Attachment 17486

My grandfather was a train conductor. He started with the CPR in the 1930s. He had a watch like this. Is is a "Bunn Special?". I've seen two. One has a 21 jewel movement with 60 hour dial. Another was 23 jewels. This watch can be used as a pocket watch or it can be clipped to a vest.

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