Our Lighting Woes (and successes)

[Aquarius]

Story time...

One night at about 4 in the morning, the security guards were making their rounds through our theatre, when they found all of the instruments in the place on at full power. It had not been like this around 11 the previous night when they came through. They called and woke up the maintenance guys, who came in, realized that something wasn't right, and went up to the catwalks to start unplugging stuff. The instruments were smoking from being on for so long. I imagine that we lost a few lamps that night... They were going to get on the lift and start unplugging the electrics, but then they found our main circuit breaker, and turned everything off.

The next day, the TD came in to see what was wrong. We have two dimmer racks, Strand, original to the theatre (15 years old), covering 96 dimmers apiece. It turns out that the only lights that were on were the ones on the 1-96 rack. it appeared that something was wrong with the control "brain" of the dimmer rack, so the TD took the brains out of the 97-192 dimmer rack and put it in the 1-96 rack to see if that would do anything. Turns out that it did, and fried the good brains that we had. So now, we have no dimmers, only the fluorescent lights in the booth and a few over the catwalks in the theatre for light. Not good.

School begins, and nothing much has gotten done with the dimmers yet. We realize that "Oh, @$#%", we have the 24 Hour Play Festival the first weekend of school. Obviously, we would like to have lights for this event.

I come in early the morning of the festival, and the TD and I mull things over. It turns out that the AC outlets still work, and we have four "circuits" of 20A each, 1 on the catwalks, one up by the electrics, 1 downstage, and 1 upstage. We decide to take a bunch of twofers and put male edisons on them instead of male stagepin. We end up getting 4 Source 4 Junior Zooms on each side of the house catwalks, along with 4 Source 4 Junior 36 degrees on each side of the stage for primitive side light.

We booked 4 crew members to run this event, figuring that we would have one SM / sound board op (me), 1 follow spot, and 2 stagehands to move the stuff on stage on and off (essential due to the fact that we were going to do 5 different plays). It turns out that we needed to operate the lights by flipping the breakers on and off. Our final setup ended up with 1 crewperson in the shop to flip the breakers for the onstage lights, 1 on one side of the booth to flip the breakers for the catwalk lights, 1 follow spot, and 1 SM / sound board op).

In spite of all this, we managed to pull the show off pretty well. And now, I have some questions for ControlBooth:

1. Any guesses on what happened to our dimmers? I know that some dimmer racks can be set to go to full on loss of signal from the light board, but the board was neither powered up nor plugged in during this time, nor was their any "loss" of signal to be had. Also, I know the electronics are supposed to let you know if a dimmer dies, but is it at all possible for dimmers to kill the electronics?

2. I recently read an article in the What Went Wrong section about how flipping breakers wore them out. i am assuming, however, that because we had no other option that we could see, it would be OK in these circumstances. Does anyone have any better suggestions?


We have some ETC dimmers on order, and we hope to get them sometime before our mainstage show goes up in the beginning of October, especially seeing as I am LDing the show. We'll see!

Anyways, thanks for reading.

 

[shiben]

Oh man, that sucks. At least you managed to get something in terms of light... Was the rack a CD-80 rack of some type? quite frankly, its surprising to me that that happened... Also, at least someone got to the lights before you had a serious fire... you could probably have had a very much worse situation.

 

[Les]

Yes, flipping the breakers is bad. Depending on how much they were flipped for this event, you may want to tell maintenance about it so they know which breakers may need replacing. The only time flipping breakers is OK is when you are about to be doing electrical work on the circuit or if there is an emergency (fire hazard, shock hazard, electrical short, etc).

The better thing to do in this situation would have been to go to a local lighting shop and rent a small control/dimming system.

As to how your CEM's failed - could be anything. But after 15 years, I'm not surprised that they're in need of some maintenance.

 

[Sony]

We had one of our Strand CD-80 Supervisors CEM fail and it did the exact same thing. All the lights on at full, fortunately switching modules did not kill the new module. Unfortunately it was a pretty expensive part to replace, at about $2,200 for a new CEM. I would get someone from Stand or a Strand dealer to come out and look at the rack, because it should not be blowing up CEM modules like that and I would venture a guess you have a short somewhere on the PCB inside the rack itself which is killing your modules. When was the last time you cleaned your racks? You should have your TD, or a TRAINED AND QUALIFIED PROFESSIONAL clean your racks. Dust builds up inside the racks and the dust holds moisture and humidity which in turn can lead to corrosion of the copper traces on the PCB which then in turn can lead to shorts and overheating of the PCB and surrounding components.

 

[FMEng]

We have some ETC dimmers on order, and we hope to get them sometime before our mainstage show goes up in the beginning of October, especially seeing as I am LDing the show.

Ordering new dimmers is one way to solve the problem. However, it seems rather drastic. The CD80 just needs a little repair. A CD80 rack in a decent operating environment should continue to do its job for many more years with proper maintenance.

Keep it cool, keep it clean, don't let the internal fans die. If the thing is badly neglected and/or cooked to death, or does not have DMX, then maybe shove them off the loading dock.

If the environment was bad for the old dimmers, it should be improved before the new ones are installed.

 

[Darthrob13]

Rack 1 was 'stuck in Panic'. This, you already know is what happens when the rack cannot find it's brain. The same thing would happen if you simply pulled it out.

The fact that putting the working brain into the suspect rack killed it points to the power supplies in the crate of the suspect rack.

Rarely (if ever) has a bad CD-80 processor brought down a power supply, but the reverse is what happened. Were I still at Strand and you had called me, I would have advised you to put the non-working brain into the working rack....but what's done it done.

15 years is a great run for original brains...now that I think about it did you have SV or AE CD-80's?

 

[tjrobb]

We ran 16 years on our 1982 CD-80 brains, with no upgrades, when a flood killed them (the brains lasted longer than some of the LED's on the rack!).

As my two cents, I must recommend troubleshooting BEFORE swapping (etc.). This is similar to finding the fault before resetting the breaker. You don't want a 120 (240) volt line faulting into your control board, and then when you start testing it faults to ground via your arm.