Control/Dimming One light changes color

I am the Worship director at a smaller church. I just finished changing all of our lighting from halogen to LED - replacing a Colortran ENR system (that was a LOT of work to remove, and now I have to figure out how to get rid of all the old equipment!). I did pretty much all the work myself, including removing the old fixtures and wiring up the new ones, building DMX over Cat5 cable, and running the cable.

Anyway, I replaced our 20 500W halogen house lights with ADJ COB Canon Wash ST fixtures. I am super happy with them - gone are the hot spots we had with the old fixtures, and I love being able to change the color of the house lights too.

Now on to the problem. I have 5 rows of fixtures, each row with a separate DMX channel. I noticed on Sunday that one of the lights in a row changed color randomly. I had them set to an orange, and one light briefly switched to red for a few seconds, and then back again. Is this a faulty fixture, or maybe a cable? or is it just a fluke. Our control board is an ETC ColorSource 40.

Either way its going to be a pain to get up there - I had to rent a 30ft boom lift to reach these lights.
If you only see this problem repeatedly happen with this fixture, then the fixture might be suspect.

DMX on CAT5 could pick up noise on unshielded cable. Are all DMX runs terminated?

Probably not.
This was our first Sunday with the new lights, so I will keep an eye on that fixture. That DMX run is not terminated, but this particular fixture is the 4th in line out of 20 fixtures that are connected together - you would think there would be issues with other fixtures. I should probably climb up there and terminate the run anyway though.

Thanks for the reply!
A terminator is mandatory, not just good practice. Without a terminator all bets are off.
Noted! Thank you. I am by no means a professional light guy, I know just enough to get things working and be dangerous lol.

I learned a lot doing the install myself, but that’s what you do when you have a thin budget and the electrician quoted 10k to do just the install. Luckily, my brother is qualified to do electrical work and did the sub panel replacement for me after work over 2 days.
Ditto on the termination. I have seen enough weirdness as our "daisy chains" grew with more LED.. Semi Flakey cable.. someone removes termination. Even good cable, terminated but long run/daisy chain.... I finally converted to artnet so that the dmx runs are much shorter and sub divided, and the last 2 shows, not random flashes at all. Took me a while to realize that dmx is a "throw...hope you catch" protocol.. no acknowlegement or real handshake... so pretty easy to get a signal that is mis interpreted somewhere along the chain when you start looking at harmonics, noise, reflection etc. Still could have a bad instrument, but I"m betting that's not your problem
Normally, as a first step, I'll suggest swapping the address of a known good working light with that of the miscreant. If the fixture behaves, the problem was in the programming. If the fixture continues to misbehave, it's either in the fixture or wiring.

Although it sounds like it's a chore to access the fixtures, the above is the fastest way and you'll probably have to get to the fixture to swap it out anyway.
But now you have the eternal theological question.... Why would God let bad lighting problems happen to good people?
But now you have the eternal theological question.... Why would God let bad lighting problems happen to good people?
Photons with free will?
Something else I noticed on budget lights is DMX rate - which I guess is how many packets per second are being sent. I had this sort of flicker issue on a Chauvet Dimmer pack using a DMX King node. It was set to sending at 40hz and I reduced the rate to 32Hz I believe. The flicker went away.
It's a problem many? people see and DFD makes a box to solve it, if you can't control it with your console or node

Another is RDM. Some fixtures don't like RDM being enabled. In a whole rig of VL2000s only 1 acted up when RDM was enabled. It would randomly decide when to respond to cues and took a while to notice that it wasn't responding all the time and also to figure out RDM was the cause.

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