Tech Talk: Troubleshooting made easy.

Posted on June 30, 2011

Mike Graham, looking pensive in front of MVP video panels

Written by Mike Graham, product manager for CHAUVET Professional

Everything breaks.
As John Bender said in The Breakfast Club, “It’s an imperfect world, screws fall out all the time.” I can vouch for this. Not only am I a product manager for CHAUVET, but I have worked extensively in the field. The majority of my field experience was on the water—as in cruise ships. The great thing about working on those ships was learning self-reliance. We did not have a lot of support beyond our own brains and had to troubleshoot for ourselves.

Searching the internet for answers had to be done from an internet café somewhere in Alaska, St. Thomas, Germany, or an even more exotic place like Miami. We had to be able to think on our feet and figure out stuff for ourselves. We had to take good notes so when we did finally get to a place where we could talk to someone from customer support we had all of the variables figured out. (We typically had only one shot per week to get one of these technical geniuses on the phone.) The funny thing is I can remember the names of every phone technician that helped me and I still run into many of them at trade shows. Some of them have become life-long friends.

Break down the system.
Troubleshooting is a critical skill we all need to have, not only in the field, but in the shop as well. The key to fast and easy troubleshooting is to break down the system to its simplest components to see what actually works. For example, if you are working on a moving light and it is not panning or tilting properly, swap the motor cables from the pan to tilt drivers and see if the problem stays with the pan. Or did it move to tilt? If it stayed with the pan, the motor is most likely the problem. If it moved to the tilt, you most likely have a driver problem. Figuring this out before you call the phone support guys will save both of you a ton of time. If it’s a color wheel, you can do the same kind of trick with the cables from the gobo wheel and vice versa. For CHAUVET Professional products, we use the same motor for both positions. It may have a different shaft length, but the motor is the same none the less. Simple things like this will save you a lot of headache.

Back up a step.
For a bigger system, it is the same principle: break it down to its basic components. Let’s say you have a club running three universes of DMX from ShowXpress. The last five fixtures on your third universe are not responding to DMX at all. First thing to do is eliminate every non-essential part of gear. Take the DMX cable from the output of universe three to the input of the first fixture that is not working properly. Now all five work, great! Let’s back up one fixture. Now you have six fixtures in line and everything is fine. Let’s back up one more step to the opto-splitter (you are using opto-splitters, right?).  Drop your DMX line from your controller right to the DMX input of the opto-splitter. If the problem comes back, you have a bad channel on the opto-splitter—problem solved. Swap it out.

Change a cable.
Let’s say we still have the same lights down. There are six lights on the line coming from the opto-splitter. Fixture one is working fine. The last five are not responding at all. You bypass the first light and find this fixes the problem. First change the cable between the first and second light. (After all, it would not be the first cable that died for no reason.) If this does not solve the problem, change the cable between the first fixture and the opto-splitter.

The next step is realizing you have a fixture problem. Since most lights send DMX from fixture to fixture without buffering the signal, you most likely have a bad DMX socket. (At least this is where I would start the process.)

Again, it’s all about breaking down the system to its simplest operation. When you call the technicians at a manufacturer, they are going to ask you if you have already done this. (If you have not, they are going to ask you to do so.)

10 tips when calling for support.
You are ready to pick up the phone and call technical support. Make sure you have the following at hand as it will help out the tech immensely:
1. Serial number of the light in question.
2. LOT number of the light in question if there is one
3. What kind of controller are you using?
4. How many are on the DMX chain?
5. Are you using an opto-splitter?
6. How many lights are plugged into one circuit?
7. How many lights are daisy-chained for power to each other?
8. What is the power level?  110, 208, or 220 volt?
9. Is it clean power? Are you on a generator?
10. How long has it been installed or in operation?

All of these questions are important for the tech you’re calling (and for you) as it helps to narrow down the scope of the problem(s).  At the end of this process, I hope your problems are solved and that your show is running flawlessly.  If not, “feel free to call us back.”