Altman LED Fixtures intermittent failure

[stumpylampshades]

So my high school has a more or less static plot that's fully LED based. All these fixtures were installed during a remodel that took place 2014-2015 and have been more or less untouched since then, besides by me (a high school senior) and one other person who does not work here anymore. More or less safe to say besides like two fixtures that are strangely aimed it's the same as it was in 2015. Over this current school year, a couple of our lights have been dramatically failing, where they start rapidly flashing through colors at full intensity and/or stay locked with one LED color at like 25-100% intensity, all Altman fixtures, though not always the same type (We've had 3 Spectra Star Pars and one SS Cyc do this so far). In addition the LCD that should display the DMX channel/other config options displays rapidly changing nonsense as well. When they do this they almost always take out the DMX signaling for the entire chain they're in, ahead and behind, making me thing they're spewing garbage data/signals on the line. They do this when left on after anywhere between 30 minutes and 8 hours, but if connected to power the problem fixtures will eventually do this.

Do y'all have any idea what might be going on and what we can do to fix it? If they need to go in for repair, where would we send them? (Minneapolis, MN Area). Any help y'all can provide would be wonderful, as I'm literally the only person in the building (and among less than like 3 people AT MOST in the entire district) with any idea what this stuff is and how to properly use it.

 

[brucek]

Might they NOT like RDM...and RDM is enabled? I do believe the original SS were not RDM compatible. Or some mechanical failure of the buttons on the control card? I know SS buttons can sometimes get stuck on the chassis and stay pressed in.

 

[stumpylampshades]

Might they NOT like RDM...and RDM is enabled? I do believe the original SS were not RDM compatible. Or some mechanical failure of the buttons on the control card? I know SS buttons can sometimes get stuck on the chassis and stay pressed in.

It could be RDM, with our Net3 setup they shouldn't be getting any RDM, though I'll poke around in concert to check that. I don't think it's the buttons given it always resets to normal after a power cycle (thank god they installed DMX relays in here) and because again, they haven't been touched damn near ever. Them failing was the reason I ever tried to bring down the electrics and this issue is new to this year.

 

[stumpylampshades]

Alright, turns out RDM was enabled on all 6 gateways, so I've turned that off, I guess we'll see if that fixes it.

 

[almorton]

Could someone have disturbed the DMX cabling? You could have a bad connection somewhere. Someone could have taken the terminator off the end of a long line for some reason?

 

[almorton]

RDM sounds likely.

 

[stumpylampshades]

Could someone have disturbed the DMX cabling? You could have a back connection somewhere. Someone could have taken the terminator off the end of a long line for some reason?

This stuff has been locked up for years the last time it could have possibly been disturbed before it was brought down to fix it was before COVID unless the rigging inspection guy really managed to mess it up, and there are terminators on each line. I'm gonna leave it powered up until it either fails or the next event (Thursday Evening) to see if it continues to do it with RDM off now.

 

[Malabaristo]

If the fixture's display is going crazy while the problem is happening, then I doubt it's an RDM or other data problem. Could be a bad power supply or other internal problem that gets worse as things heats up. I've never had to seek out service for Altman products, so I don't know where to direct you, but sending the problematic fixtures out for repair is likely to be necessary.

 

[FMEng]

I have commented about this before. Most non-consumer electronic devices made these days use switching power supplies. Switching supplies produce quite a bit of amount of heat. The compact form factor puts the heatsinks in close proximity to electrolytic capacitors, so the capacitors run warm. Capacitors do not like heat and their life span is inversely proportional to their temperature, so the supplies tend to cook themselves to death. Well designed electronics could, in some cases, run reliably for decades, but that is rare today and this is a very common cause.

If the fixtures have been powered up since they were installed 10 years ago, then we can guess what is happening. The supply rails are dirty and unregulated, cause the microprocessor to go wild or into a reboot loop. Chances are that just replacing a supply module will keep them going for another 10 years. Hopefully, Altman can replace the supply modules or supply parts to a local tech. If the supplies are indeed found to be going failing, then you might as well change out all of them.

LED stage lights cannot last like the incandescent predecessors did. Instead of bulbs and sockets, which were an simple and cheap fix, now we have electronics with finite lives. We've traded the inconvenience of burned out bulbs for a more expensive but far less frequent problem. On the bright side, the electronics quit before the LEDs fade to half brightness.

 

[TimMc]

I have commented about this before. Most non-consumer electronic devices made these days use switching power supplies. Switching supplies produce quite a bit of amount of heat. The compact form factor puts the heatsinks in close proximity to electrolytic capacitors, so the capacitors run warm. Capacitors do not like heat and their life span is inversely proportional to their temperature, so the supplies tend to cook themselves to death. Well designed electronics could, in some cases, run reliably for decades, but that is rare today and this is a very common cause.

If the fixtures have been powered up since they were installed 10 years ago, then we can guess what is happening. The supply rails are dirty and unregulated, cause the microprocessor to go wild or into a reboot loop. Chances are that just replacing a supply module will keep them going for another 10 years. Hopefully, Altman can replace the supply modules or supply parts to a local tech. If the supplies are indeed found to be going failing, then you might as well change out all of them.

LED stage lights cannot last like the incandescent predecessors did. Instead of bulbs and sockets, which were an simple and cheap fix, now we have electronics with finite lives. We've traded the inconvenience of burned out bulbs for a more expensive but far less frequent problem. On the bright side, the electronics quit before the LEDs fade to half brightness.

^^^ This. All of it, but especially the part in bold.

Switch mode PSUs can dump lots of harmonics back up the neutral, too, and other PSUs may be sensitive to them. When you see 11th, 13th harmonics on the power quality monitor...