Hemingray:
Good call on the fuses. Yes they are clearsite fuses. The only spares left in the theater are modern style though.
![[Linked Image]](https://www.electrical-contractor.net/ubb/frown.gif)
It says something about the quality of the original workmanship that a majority of the fuses on the lighting circuits are still intact!
To cintinue the commentary:
#10: A close-up of the contactor busses. Beautiful layout and decent clearances (the pic angle gives the opposite impression.) I need to mention that the way this system is layed out is the dimmers and deadfront mount through the booth wall, then there is a working gap of about 28", then the cabinets holding these contactors and fuse panels. There are overhead busways (at about 6' above the floor) between the two cabinets. The contactors and fuses face INTO the rear of the dimmer board. More on that later...
#11: The plate style resistance dimmers....and yes that copper buss is live!
#12: Close up of the dimmers. The handle rotates the double sliding contacts(180 degrees apart) over the buttons, which are attached to the resistance elements imbedded in the ceramic. They are designed to dim the rated loads to dull glow, not full black. For complete blackout, the respective contactor is opened.
#13: This is the dimmer for the blue wall wash, which suffered an arcing failure intense enough to MELT the ceramic!! If memory serves, the contactor which flamed out in the pervious thread was also on this circuit.
#14: A plethora of plug fuses. A surprising number are still original.
#15: A closeup of some plug fuses and the disconnect switches for same. IIRC the switch disconnects the power to the cartridge fuse which acts a a sub-main for the select plug fuse circuits. The clearance to the cartridge fuse and that door is extremely tight, you wouldn't want to try to pull that fuse hot!!
#16: And here's the motor which drives the grand master dimming linkage which allows for smooth dimming of many circuits. This can be controlled at the main board, at EACH of the three film projector locations, at the spotlight location and at the switchboard on stage! Activating it results in a loud clunk from the contactors on the left, a deep hum from the motor and squeaks and groans from the dimmer linkages!
As I'd mentioned, working space is tight behind the dimmers and in front of the contactors. The dimmer bays are open for ventilation, and you have to be very careful when walking thru or working in that area to avoid hitting a live busbar! I had a safety spotter with me when I took these pics to make sure I didn't back into anything live.
Again, it does say a lot for the original designers and builders that the majority of this system still works and with very little attention. I seriously doubt that any of the modern stuff today will still be operational in 75+ years!