Automated Fixtures DMX Terminator causing flickering?

Sorry if this has been addressed elsewhere, but I couldn't seem to find it.

Here's the situation. About two years ago the Head Technician at my theatre bought 15 Chauvet COLORado 1-Tri Tour LED instruments that we use as a down wash on our three electrics. They worked beautifully and we were very happy. So he convinced us to then purchase Chauvet COLORado Ridge IPs as a solution to our dying cyc lights. And again we were happy and they worked fine.

Just recently though, they've begun to act... funny. Nearly two years after install the cyc lights began to intermittently flicker, and then rather frequently flicker.

I did a lot of research, and reading on this website actually, and realized that we had never placed a terminator on our DMX daisy chain of 21 instruments. So, logically I purchased one from technical theatre industry leading giant amazon.com and as soon as I pluged the terminator in to the end of the daisy chain, the Cyc lights stopped flickering. Viola! Problem solved!!

UNTIL!! I looked to my left and notice that the down light became like an addicts eyes after 2 days of detox; BLINKING LIKE NO ONES BUSINESS. But as soon as I removed the terminator _____________ solid, except of course the cyc lights...

Now, our run IS rather long and I've looked into purchasing wireless transmitters and receivers but I don't think that will necessarily solve the issue that the terminator makes everything act a fool.

Any advice would be appreciated!
 
Could you be possibly using a "passive" splitter (aka, a Y cable)? If so, that could be to blame. DMX has to be actively split.

Well, everything is simply daisy chained, in and then back out. Though... the COLORado Ridge IPs have a single cable that comes out and splits to male and female DMX. But that's a factory install. Came that way. Could that be something that would cause the issues?
 
... and as soon as I pluged the terminator in to the end of the daisy chain, the Cyc lights stopped flickering. Viola! Problem solved!!

UNTIL!! I looked to my left and notice that the down light became like an addicts eyes after 2 days of detox; BLINKING LIKE NO ONES BUSINESS. But as soon as I removed the terminator _____________ solid, except of course the cyc lights...
You've got a bad cable (or more than one) somewhere. Could be anywhere.
http://www.controlbooth.com/threads/moving-light-freakout-terminator-was-the-problem.28635/

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... Now, our run IS rather long and ...
"Rather long" in DMX terms is something over 1000-1800 feet: http://www.pathwayconnect.com/content/view/61/26/ .
http://www.controlbooth.com/threads/max-length-of-running-a-dmx-daisy-chain.27999/
 
Did someone substitute mic cable for DMX cable somewhere in the chain? The cable must be of the correct type, especially in a big, long chain.
 
Did someone substitute mic cable for DMX cable somewhere in the chain? The cable must be of the correct type, especially in a big, long chain.

Very likely, all of the fixtures are 3-pin. My students tend to think they know more than they know. That'll be a fun troubleshooting experience. o_O

Thanks for the reply!
 
If you are curious why adding a terminator may have caused some fixtures to misbehave, there is actually some logic behind it. Although you defiantly have something compromising the DMX signal, adding a terminator actually lowers the signal level a bit. It cleans up noise, gets rid of standing waveforms (electronic echos) and is always recommended, but it also loads the line down a bit. This is by design and a properly running system will have better performance. But, in situations where the signal is being compromised, it can have adverse effects for two reasons:
1) a shorted cable may be removing half the signal, or another terminator (some fixtures have a terminator switch, but not Chauvet to my knowledge) may be in the chain. In this case, the lowered level may mean that fixtures that were just catching the signal before can no longer read it.
2) an open cable with a broken connection on either pin 2 or pin 3 now ends up with the + signal and - signal in phase via the terminator.
 
Probably a bad cable, it can be anywhere in the chain, start at your first fixture, unplug the dmx out, check, move to the next light, unplug the out, and work your way through.
I like to make a chase or cue stack that just changes from red to blue with a 1 second delay, that way it is easier to tell if everything is good, compared to a static color.
 
Just an update. Bought all new DMX lines as well as wireless transmitter/receivers for each electric as well as terminators for each electric. Bypassing almost all significant lengths of DMX while also separating each electric to it's own daisy chain. All problems fixed! Thanks for all your help, turns out the original install was done, as predicted, with microphone cable and great lengths and lots of them (including to 50' cables that were strung from electric to electric.) o_O. I appreciate you all dealing with a newbie!
 
Just an update. Bought all new DMX lines as well as wireless transmitter/receivers for each electric as well as terminators for each electric. Bypassing almost all significant lengths of DMX while also separating each electric to it's own daisy chain. All problems fixed! Thanks for all your help, turns out the original install was done, as predicted, with microphone cable and great lengths and lots of them (including to 50' cables that were strung from electric to electric.) o_O. I appreciate you all dealing with a newbie!

We are all most eager to help out a 'newbie'! I'm sure I am not the only one who is pleased that you solved the problem (and removed the microphone XLR). Just another illustration of how many believe something is 'good enough' and it never is. Isolating DMX splitters, proper DMX cable and terminators are three things that will solve SO VERY MANY problems with DMX signal.
 

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