Kliegl 12kw SCR Dimmers

DavidNorth

ETC Rigging General Manager
Premium Member
Fight Leukemia
Departed Member
Joined
Jan 21, 2009
Location
Madison, WI
These are R series dimmers that are earlier in the available model line. The SCRs are monstrously large bolt-on type and the chokes are potted. Control voltage would likely have been 0-28vdc as 0-10vdc came later with the use of adapters cards plugged into the back of the firing cards. Many systems were converted to 0-10vdc as computerized controls came about, however, I seem to remember that the Performer II could optionally output 0-28.

Nice pic!
 

robartsd

Active Member
Joined
Apr 18, 2011
Location
Sacramento, CA
I know that modern lighting has gotten more efficent, but I can't imagine any design needing anything close to 96 dimmers @ 100 amps each.
 

JD

Well-Known Member
Joined
Jan 1, 2005
Location
North Wales PA
I know that modern lighting has gotten more efficent, but I can't imagine any design needing anything close to 96 dimmers @ 100 amps each.
Well, one "old fashion" design technique was to load a whole sub-scene on each dimmer. In that case, you might have 10 instruments per channel on many of them. Something about running 12/3 on a 100 amp dimmer was very un-nerving. In most cases, the patch pay broke that down to 20's.
 

robartsd

Active Member
Joined
Apr 18, 2011
Location
Sacramento, CA
Well, one "old fashion" design technique was to load a whole sub-scene on each dimmer. In that case, you might have 10 instruments per channel on many of them. Something about running 12/3 on a 100 amp dimmer was very un-nerving. In most cases, the patch pay broke that down to 20's.
That would make sense if the control board didn't have any sort of preset system - one can only move so many handles at once. I just can't imagine a design aproaching 96 sub-scenes as such (or the space to hang that design).
 

Zebulon1880

Member
Joined
Jan 31, 2015
Location
Oakland, California
image.jpg
These are R series dimmers that are earlier in the available model line. The SCRs are monstrously large bolt-on type and the chokes are potted. Control voltage would likely have been 0-28vdc as 0-10vdc came later with the use of adapters cards plugged into the back of the firing cards. Many systems were converted to 0-10vdc as computerized controls came about, however, I seem to remember that the Performer II could optionally output 0-28.

Nice pic!
When we purchased the Kliegl Performer One, Kliegl Bros. installed an interface to convert the 0-10v from the Performer to the 0-28v dimmer control voltage. The 0-28v interface output was wired in parallel with the 5 scene preset board, thus allow control from both boards simultaneously. The high control voltage level determined which board level setting would appear on the dimmer voltage output.
 

Zebulon1880

Member
Joined
Jan 31, 2015
Location
Oakland, California
And yet, a 5 rack (96x2.4) system today is still considered a medium-large installation.
When the UAF Theatre (Fairbanks, Alaska) was built in 1971, the Alaska Pipeline was under construction. The state had billions of dollars in its coffers. I suspect that Klieg Bros. took advantage of this, and installed an overrated load capacity double of what a normal maximum load capacity most theaters required. Thus allowing a good profit margin in the contract.
 

rbalewski

Member
Joined
Aug 18, 2014
Location
Scranton, PA
The above photo reminded me of an old light board I used to use at a local college. I don't remember the brand, or maybe it was even a custom thing. Maybe someone here will know what it was from my description?

It was 60 channels. The "main" desk had a row of 60 small individual channel faders and 3-position switches (for off, fade, and on, if I remember correctly) across the top, then in the bottom right corner were 10 submasters for the 10 presets. There were some controls for house lights on the left, and the whole center area was empty - very convenient for script and cue sheets.

Off to the side was the preset wing. It had 10 rows of 60 sliders (they traveled in an arc, rather than completely linear, if I remember correctly) for "loading" the 10 presets.

The thing was quite archaic by today's standards, but back then, I was used to piano boards or, at best, two-scene boards. So using that monster was a dream!
 

venuetech

Well-Known Member
Departed Member
Joined
Apr 14, 2008
Location
AK,
That was 0 to 28 volts John, for the longest time I thought 0 to 10v was weird.
The photo with the young fellow shows the 5 scene preset board.
Do you have any photos of the lab theatre board?
That was something like a 14-20 channel board that had reader cards for the preset.
 
Last edited:

Zebulon1880

Member
Joined
Jan 31, 2015
Location
Oakland, California
That was 0 to 28 volts John, for the longest time I thought 0 to 10v was weird.
The photo with the young fellow shows the 5 scene preset board.
Do you have any photos of the lab theatre board?
That was something like a 14-20 channel board that had reader cards for the preset.
Yes I know the main system control voltage was 0-28v Tom. The Performer was 0-10v. I don't have photos of the lab theatre board. I think it was 24 channels.
 

BobHealey

Active Member
Joined
Aug 6, 2011
Location
Troy, NY
This photo was taken in 1985. I don't think DMX existed then.
I was using a 194 circuit K96 rack in 2005 that had been retrofitted with DMX in the late '90s. Was all quad 1KW packs with a single dual 2.4KW module. The system was replaced when no approved vendors could service it anymore. The pack connectors and fuse holders on the quad 1K packs were wearing out. Consoles that drove that rack were a Performer, an Entertainer, a Colortran (When the DMX conversion happened), a Lehigh Millenium, and the console at time of retirement was an Emphasis setup. Still a few modules in that building that resurface every few years to perplex people who don't know that lighting equipment doesn't need to have the letters E, T, and C stamped on it.