Control/Dimming - Lighting Problems- grandMA

[lambdog04]

Im having a lighting problem. i have a grand ma. one day i came in and turned on the board and just about every light in my rig was going nuts. All the faders were down. I hadnt even done anything yet. I have 14 vl3000's, 4 vl3500's a bunch of pars and likos, and 26 color blast 12's. But like i said i turned on the board and you could hear the vl's strobing, the color blasts were changing colors and flickering, and pars and likos were blinking. This lasts for about ten minutes, then it stops. i also have a ghosting problem with one set of color blasts. its a set of four. They are on a pds-150 power supply. They will not stop flickering when the board is on. Ive changed the dmx cable, ive moved the power from one input to another and it still does it. what could be the problem?

[Van]

I'm sure you'll get some more, and better, input soon but the first question I would address is termination. Go back and double check everythingmake sure your runs are properly terminated. If you are running through a opto splitter then remove all the cables and plug them back in one at a time se if just one of the lines makes all the others freak, if so then you know your issue may be in that line < although if using an Opto-isolated splitter this shouldn't happen at all.> The ghosting issue also sounds like a termination issue.

[Grog12]

Originally Posted by lambdog04

Im having a lighting problem. i have a grand ma. one day i came in and turned on the board and just about every light in my rig was going nuts. All the faders were down. I hadnt even done anything yet. I have 14 vl3000's, 4 vl3500's a bunch of pars and likos, and 26 color blast 12's. But like i said i turned on the board and you could hear the vl's strobing, the color blasts were changing colors and flickering, and pars and likos were blinking. This lasts for about ten minutes, then it stops. i also have a ghosting problem with one set of color blasts. its a set of four. They are on a pds-150 power supply. They will not stop flickering when the board is on. Ive changed the dmx cable, ive moved the power from one input to another and it still does it. what could be the problem?

That would be an uber termination problem if thats what it is. What kind of show is it? If its full off effects and the like make sure you Off Off everything before you shut the board down. Also give that a try during the ten minutes of 'fun.'

Do you have an old backup of the show off board? If so load that (after making a copy of the current show onto a disk) and see if thats the problem.

Also is your software up to date? One of my favorite Ma issues (it would continulosly crash everytime we tried to delte cue 183) was fixed by updating the software.

how many universes are you running? Is there an iso-opto? At a guess you're at two universes which makes it seems more like a board/software issue than a cable issue...but not completely positive on that.

[derekleffew]

Is there an NSP involved?

[TheSwami]

Also, have you re-run any DMX or power cable recently? Running DMX (or any signal cable) next to mains power or even multi or jumper can cause interference in the DMX signal and possibly corruption of data.

We had problems with twitchy scrollers last year during a local dance concert; turned out the DMX run from the console back in the booth to the cove where our scroller power supplies were was lying right next to the five multi's we had running out there. Just moving the cables to the opposite sides of the 3' walkway solved that problem tidily.

73

[Grog12]

Yeah I've had Swami's problem too. At an unamed location they but the back-up generator for the otherside of the campus next to our dimmers. Someone pushed the test button on the generator and there after it would go into a test mode at the same time each week....really screws up a tech when you're lights flash for no reason.

[Sony]

Originally Posted by Grog12

Yeah I've had Swami's problem too. At an unamed location they but the back-up generator for the otherside of the campus next to our dimmers. Someone pushed the test button on the generator and there after it would go into a test mode at the same time each week....really screws up a tech when you're lights flash for no reason.

That's not Test mode, that's Exercise mode. Diesel Generators in particular and just generators in general need to be run for about 20 minutes each week to keep them in top condition. It keeps the oil from draining completely out of the engine causing dry startups, it keeps the fuel from becoming stale from sitting in the tank for too long and also allows the engine to do a diagnosic check every week to make sure everything is working. All the generators on my schools campus and the one at my job do this at a set time every week, usually early in the morning or late at night. The one at the theatre at my college runs for 20 minutes every Tuesday at 2pm and the one at my work runs every Saturday at 7am. Ask your head of maintenance to change the weekly exercise time to some time when you wont be having a show, such as early in the morning like 7am. I'm sure if you explain the issues they will understand.

I can tell you a story about a generator close to my school that didn't have this feature. A gas main exploded at one of the school buildings on my campus (Don't ask how...we never found out) and caused the fire department to give an order to cut the power to the whole town. Well that causedn a generator close by at a Pre-School to activate, this generator wasn't well maintained and didn't have an exercisor or diagnostic check recently. Well...to make a long story short...it exploded and took out an entire wall of the Pre-School. Luckly it happened at night around 9pm when no one was around.

[Grog12]

This was years ago Sony....the funny story is that the head of mainenance had to come out to figure out what was going on. His subordinates never could. They fixed that problem after only 6 months.

[beltsvillecrucib]

I have zero experience with the MA, but could it be possible that there is a macro set to run on startup? Only reason I have to believe that it is not a problem due to power is that you say it runs on startup of the console, which should really not have anything to do with the powering of the fixtures unless you are powering the fixtures through relays in dimmer rack.

Not really sure about the ColorBlast problem. I would suspect a cabling issue somewhere along the line.

[Grog12]

Originally Posted by beltsvillecrucib

I have zero experience with the MA, but could it be possible that there is a macro set to run on startup? Only reason I have to believe that it is not a problem due to power is that you say it runs on startup of the console, which should really not have anything to do with the powering of the fixtures unless you are powering the fixtures through relays in dimmer rack.

Not really sure about the ColorBlast problem. I would suspect a cabling issue somewhere along the line.

What we're talking about belt is electomagnetic interference. Basically the gennie throwing interference into the dmx line much like the mariachi radio channel throwing it into unshieled sound cable. It wouldn't happen when the board was off because no signal would be passed from the board to the fixtures. When the board is on...signal is passed and screwed with by the gennie.