I did quite a bit of testing with my iDMX powered from just the USB485B... Two separate iDMXs ran the whole season just powered from adjacent controllers, but in both cases, there was less than 5 feet of cable from the controller to the iDMX, and there were multiple controllers nearby that could contribute power...
I will say that it appears that some DMX hardware is just as robust as LOR about running without terminators, to the point where they aren't even recommended, and other hardware just about requires termination...
Also, if the fixture is acting like termination is an issue, it might also be a good idea to look into DMX cable instead of microphone cable.. The O-ring sealed outdoor DMX cables I'm using aren't cheap, but they do seem to be a first rate product...
Maybe you said this already, but did you try changing the polarity on the iDMX? I had this exact problem at our Hospital display - after a few days and every test I could think of, I read a small blurb about polarity in the iDMX. Flipped the switch on the iDMX, everything worked perfectly. And then I kicked myself for wasting 2 days.
Well after about a whole day of troubleshooting I have come to the conclusion that it is my light that is broken. Several things happen that lead me to this conclusion. I did everything that you people told me to try...bought a wall wart, added a terminator, updated the firmware, move the light away from anything that could cause interference...I even bought a 45 dollar cable...nothing changed how the light functioned. I know that the iDMX is working fine because for the few seconds that the light does work, it works fine. There is a signal light on the Min Spot that should blink steady when it is receiving a signal from a DMX controller. That blinks in very odd patterns. Usually it isn't even on at all. This tells me that it just isn't getting the signal. What is even more interesting is when the terminator isn't installed the light has more of a chance of getting a signal. When it is in, it never gets a signal.
I am going to call Chauvet on Monday and see what they say. Thanks everyone for the help!
Sorry man, sure sounded like the exact same polarity issue I had. All I had to do was flip the switch on the iDMX and everything was perfect. Sorry that didn't work - good luck!
I thought I would update everyone on what actually happened with my light just in case somebody else is having the same issues.
My first problem was the fact that my iDMX was broken. As per usual, LOR Support was amazing and I had a new one in my hands within one day. You can't ask for anything better then that!
Once that was working I was still having problems with my light. I ended up contacting Chauvet and they had me do a few things to the light, powering off and on cycles, which eventually didn't do anything. Their support was surprisingly helpful as well. Once they figured out that something clearly was not working, they had me send the light back. Today I got the light back and the fixture itself had a bad DMX input. They replaced that and sent it back to me. Now the light is working perfectly and has been running all day long with no issues what so ever.
One thing I learned from this is please remember that a terminator is a must. Chauvet had me use it and when I did use it things worked better, but not great. That is when they figured out something was wrong with the input. One thing that I find, especially with the MiN Spot is that it does not like a lot of "noise" around it. The light is next to my computer with my monitor and that seemed to hurt it as well. Chauvet had me move the light away from this stuff, again nothing worked. Even now that it is working fine, when it is near all the electronics, things really seem to go a little fishy. Once the terminator is in, it works great.
DMX really adds some nice things to displays and I can't wait to keep adding more fixtures to my display.
Thank you for the update.. Glad to hear you have it resolved, and very glad you got started with enough time to get it all worked out in advance!!
Termination requirements do really depend on the particular hardware involved.. We contacted the vendor of our LED wall washes, that use the O-ring sealed DMX connectors with rings that screw down to pull the seal tight, and asked them about obtaining a terminator that would work with those connectors. Their response was "Why? We have customers with far more than the 15 units you are using in a chain, and have never heard of any issues where termination was needed"
So, it does appear to depend on the DMX hardware you are using, as well as cable quality, length, and ambient RF interference sources. But, without a doubt, if you are having issues, try installing termination.
