MEP Engineering Solutions Ltd.

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Elevator Controller With A Mercury Arc Rectifier.

The large glass tube with the blue glow is a mercury arc rectifier, which was used to convert alternating current (AC) to direct current (DC).
This type of equipment was used in older elevators to power the DC motors that controlled the lift.
The system shown is likely over a hundred years old.
The components visible include the mercury arc rectifier, switches, and other electrical components.