Dimmer Racks?

For the past year or so we've been having to reset the dimmer racks at least once a day, sometimes more. Just wondering if there might be a problem there.
 
In addition to what brand....what do you mean "reset". Are you having to power-cycle the racks? Reset the config?
 
They are ETC Sensor and we just hit the reset button. What happens is areas 1 through 5 or sometimes 1 through 10 won't come on and we've been told to reset the dimmers when that happens and it's been happening a lot more frequently than it used to.
 
That doesn't make sense.

That's the Reset button on the CEM, I presume.

I don't see what would be going on inside the CEM that would affect only the dimmers that drive your downstage and sometimes midstage fronts. Those are most certainly going to be on nonconsecutive dimmers in the rack.
 
They are ETC Sensor and we just hit the reset button. What happens is areas 1 through 5 or sometimes 1 through 10 won't come on and we've been told to reset the dimmers when that happens and it's been happening a lot more frequently than it used to.

When you say that areas 1-5 won't come on, how do you mean? Do you mean you try to bring up some channels on the board and the lights don't come on? First off, I think you need to be a little more specific in what isn't working as we don't know what your areas consist of. Do you mean that there are five lights that won't come on or do you mean that 4 four or five lights for each area won't come on?

Is your installation just Sensor racks or do you have Sensor+? Does the CEM display any errors when you go to reset it? Where do your dimmers live, are the in their own room or do they live on stage or some place where they might collect lots of dust from building scenery? If the air filters on the racks get clogged up and not enough air gets through the CEM will shut down the rack. Also, the original CEM had an issue where it's onboard airflow sensor would get clogged, and even when the rack was clean it would shut it down, so check that as well. you might also want to reseat the CEM in the rack, if it is making a loose or bad connection it may not be able to always get data out to the dimmers.

Here are things that I would check. First I would make sure that all the dimmers are set to the correct firing mode and that none of them are held at any level by the CEM. If you set a level for a dimmer on the CEM it won't respond to the board. If the settings are correct then I would try swapping the dimmer in question with a known working dimmer. If the problem stays with the same lights then the issue is a control issue, however if the problem moves with the dimmer then you know that the issue is with that particular dimmer card.

After that, if you can't figure it out just call ETC Tech Services at 1-800-688-4116. They will be happy to help you.
 
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By the way, we've thrown the term "CEM" around quite a bit here without clearly stating that it stands for Central Electronics Module or something of the sort: it's the brain in the dimmer rack. The DMX control signal feeds into the CEM, and then it makes the dimmers fire accordingly. Sensor CEMs have lots of microprocessor on them and can do really smart things.
 
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Sorry I wasn't specific enough. I don't really know much of anything about dimmers so I didn't know what to say.

Yes they are Sensor +.

By areas 1 through 5 I mean that the 3 lights in each of the first five areas will not come on. Yes, when we try to bring up channels nothing happens.

Sometimes it displays errors sometimes it doesn't.

The dimmers are in a room of their own.

Danny says he thinks they are overheating but we aren't sure.

And, I'm sorry but I can barely understand you guys at all. The only thing I know about dimmer racks is to reset them when the lights don't work, and which button is the reset button.
 
Well, lets start at the beginning. In your dimmer rack at the center is the control module or CEM. This is where your reset button is. The CEM has an LCD display that will give you information about the rack. Any serious errors will also cause the beacon at the top of the rack to flash. On the right hand side of each dimmer module you should see a pair of green LEDs next to the word "Signal." When you turn on a channel at the board, whatever dimmers it controls should have that LED lit.

Next time you have this problem where the lights don't come on, do this:
1) Check to see if the dimmers that should be on have a green signal light
2) look at the LCD on the CEM and see what it says.
2A) If it says "rack errors" push enter (the check mark button) and it will display them. You can scroll through the errors with the up and down buttons.
2B) If there are any errors, write them down and tell us (or call ETC and tell them)​
3) Inside the door of the rack are two air filters, check them to see if they are clogged. If they are clogged, clean them out!
4) When you turn dimmers on, make sure that the rack fans are running.

Also, just for info, look at the numbers to the left of the dimmers, do they go in order or do the go: 1, 2, 7, 8, 13, 14....?

If you can, take a couple pictures of your setup and any error messages and post them, it may help. Also, if you know who installed the system it may be worth giving them a call, or call your local ETC dealer. Once again, don't hesitate to call ETC Tech Services!
 
Probably never. So...three years ish. (for cleaning)

Thanks icewolf08, I'll do that.
 
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Don't forget to vacuum the slide-in filter in the door too.
 
Ok I looked at the error messages.

And, theres four on the left side of the room, two of which had errors.

3. Clean your filter (yes, self explanatory I know.)
4. Ambient Overtemp

and then there's two on the other side, both of which had errors.

1. No data port
2. No data port

Ok I get error 3 but the others I don't.
Help?



Oh, and the filters were cleaned out about a year ago.
 
The Ambient Overtemp is telling you the Dimmer or the CEM is failing because it gets too hot. One version of the ETC CEM's had a design flaw solved by ETC adding an airflow "snorkel" (their term, not mine) to the motherboard to improve airflow. I had three CEM's "rennovated" over the first 4 years our venue was up do to this problem. When that failure would happen, you would see lights fluttering instead of not coming on.

Double check that your Dimmer Room as air conditioning to keep it cool. That helps a lot.

The No Data should also say A, B, etc. that tells you where no data is coming from.

The No Data message also tend to mean control data is not getting to the racks.

All in all, I think an ETC Service trip might be in order. Find out who your local Qualified Service Vendor is and get the call made.

You should not have to reset the CEM's the way you are.
 
After that, if you can't figure it out just call ETC Tech Services at 1-800-688-4116. They will be happy to help you.

It's time to call ETC. Trust me, they are really nice people... heck half their company hangs out here on CB. Just give them a call, tell them you are a student and don't know a lot about dimmers, explain your situation they will tell you what to do and I'm sure they won't be intimidating. Situations like this are exactly why they have that phone number. Don't be shy, give them a call.
 
You have six dimmer racks?

Yeah. I'm told that two of them are for the new black box.


The No Data should also say A, B, etc. that tells you where no data is coming from.

They say A.

What does that mean?

Yes, I know I should call ETC. I will get around to it, probably this afternoon, but...it sounds like I'm kind of screwed because Smith isn't going to let me have them come or anthing. :/
 

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