Good call on the fuses. Yes they are clearsite fuses. The only spares left in the theater are modern style though.
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!
Stupid should be painful.
#152727 - 12/18/0504:10 AMRe: Avalon Theatre - Part 2
I used to do a show every year in a 1923 era building with a dimmer system very similar to this.. As with this one, much of the original wiring was still servicable, althought there were some notable exceptions, such as the multicable to one of the X-rays (overhead 4 circuit border lights).
This facility had some more modern dimmers added for additional control, although the installation of those was a bit sketchy..
I used to bring in a complete lighting system, with a touring dimmer rack of 48x2.4k dimmers, multicable, fixtures, control board, etc.. I tied in power directly off the live busses in the power room, which was full of contactors as shown in the previous series of photos.. The tie-in was done hot, using Mole lugs, as the only way of de-energizing was to kill all power to the entire floor. Unlike this installation, I had 5-6 feet of working clearance.. It was actually one of the easier tie-in's that I have done, despite it being a hot tie-in.
Mole lugs are lugs designed for the motion picture industry, that slip over a busbar, and clamp down with a bolt. It used to be common to have junction boxes with several compartments, each with a short section of bussbar, onto which the mole lugs were clamped, similar to these:
Thanks for posting these pics; the younger crowd simply can't imagine how anything was ever controlled without using mysterious black boxes of electronics!
Likewise, there WAS life before circuit breakers.
That this stuff is, even today, perfectly safe and adequate says a lot for the original design. Sometimes people forget that :real" electricians actually consider the customers' application- rather than doing the absolute code required minimum!
#152732 - 12/18/0512:37 PMRe: Avalon Theatre - Part 2
A big you're welcome to all who commented and again thanks to Bill for posting these. I also sent in some more pics, of the projection equipment and old motor-generator there which is also still fully operational.
As I'd mentioned in part 1, those contactors are the main source of trouble there. And so far, neither the building maint. super nor I have been able to locate any kind of spares or source for replacement parts. The current line of thinking is that they'll have to somehow adapt modern open contactors to repalce the ones that failed.
As techie mentioned, to de-energize this would take out (in this case) the entire booth [lights too!] and a good portion of the mezzanine level. I guess sparkies back then worked things hot a lot more than we do today. (Of course, we tend to survive longer now too.)
Stupid should be painful.
#152734 - 12/19/0510:42 AMRe: Avalon Theatre - Part 2
Mxslick: The pix are fascinating! Thanks for sharing them with us. This really brings back memories of work I used to do on an old Hub Electric board, which used similar contactors and autotransformer dimmers. Does this board control any stage lighting, or just house lights? Do you service the stage switchboard as well? Is it also a Frank Adam?
These old boards are really rugged guys. I'm sorry to hear that the contactors are starting to give out. Is there a lot of "chattering" going on here, since you mention the presence of copper dust? I hope you will be able to find some replacement for the contactors.
#152736 - 12/19/0501:23 PMRe: Avalon Theatre - Part 2
It's almost the same stuff that's still in place (and operational!) at the Loew's Jersey theatre in Jersey City.
That theatre is slowly being restored by volunteers and it seems like the idea is to keep as much of the original stuff as possible
... Sven,.. I had the pleasure of touring that theater in Jersey City,.. with a friend who is on the commitee to save her,.. Unbelieveably gorgeous... that's all I can say,.. we toured the loft(attic) to the sub-basement,.. it was truly a step back in time,.. I was like a wide-eyed little kid looking at a candy factory,..
Mxslick,.. GREAT freakin' pictures, man,.. I love all of this stuff!! Keep 'em comin'... Thanx, Russ
.."if it ain't fixed,don't break it...call a Licensed Electrician"
#152738 - 12/20/0501:23 AMRe: Avalon Theatre - Part 2
Wow! Glad to see all the interest in this thread! Thanks all!
Mike: This board controls a mix of stage lights and all of the house lights (Chands, wall wash, pinspots for star efx, etc.)
I haven't serviced the stage board, I really don't do any work on this one other than a visual inspection and try to point out potential trouble. The theatre has an electrician who is so backlogged with work that everything is handled on crisis basis anyway. (The theatre is part of a HUGE building which also includes a grand ballroom on the top level. Those who have seen pictures of Catalina Island, this is the big round building with tile roof and cupola on the Avalon shore.)
Yep, this is a Frank Adams installation. If memory serves, virtually all the surviving old panels throughout the building are F/A.
No, the contactors don't seem to be chattering, but after so many thousnads (millions?) of cycles wear is becoming a factor. All the worst ones have visible wear on the pivot points and the springs at the contacts. So far, we haven't been able to locate any parts for these at all.
Nope, see above. Can't locate parts and like most businesses, they won't pay for custom parts made to fit. I am trying to see if there's any way to get an inactive contactor removed so I can shop it around to try to get parts fabricated. As you can see in this thread and the other, the whole board assembly is modular. But I am uncomfortable with the idea of working it live to remove a contactor.
Thanks for the kudos! I'll try to get some more next time I'm there. They have some original motor starters for the pipe organ blowers, and the main vault is interesting to say the least!
Stupid should be painful.
#152739 - 12/20/0509:03 AMRe: Avalon Theatre - Part 2
Mxslick: in pic no. 16, above the linkage drive motor, there appears to be some type of electric device, I'm assuming attached to one of the dimmer row shafts. Is this some kind of a limit switch to prevent the motor from rotating the shafts past it's normal range of movement?
#152741 - 12/20/0510:45 PMRe: Avalon Theatre - Part 2
All of the lamps are 120 volts, IIRC there are no 240 volt loads served by either this board or its mate on the stage.
The supply is also IIRC 3 phase delta. (The poco here in So Cal which also serves the island had a huge love affair with delta, even using it extensively at the distribution level, 4-34.5 Kv.)
As I'd mentioned, I had a chance to see the main vault room. The main switchgear was mostly modern circuit breakers, adapted to an original bus structure from the old gear. It not only gave me the "willies" being in the same room, but the heat coming from it was considerable.
The transformers serving the building were benind a concrete dividing wall, with "Pillbox embrasures" (6x12 inch slots) so I could peek in there too. 34.5kV incoming, a trio of individual submersible type transformers wired with what looked like XLPE concentric cable primary and three large (500Kcmil?) secondary per leg.
The interior of the vault showed extensive blackening from a secondary cable fire and the failure of the original oil filled transformer some years ago.
If I can get to the vault again on my next trip, I'll try to get pics.