Electronic Theatre Controls

I am having a "flashing" issue with my sensor 96 and 24 racks. Some of the dimmers will come on and then in about 15-30 sec of being on they flash off then on. Is this just a module issue in the SSR or the CEM?

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Mick

A little more info might be necessary to try and help...

Are these install or tour racks?

Is the problem happening in both racks at the same time?

Is the same power source fed into both racks?

How is data fed into the racks?  hard-line dmx, network, any daisy chain, or data iso splitters?

Is this the older CEM processor, or the new CEM+ processor?? 

Remember you can always call Tech Services if this is urgent... 800-688-4116 

-Bob

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Bob Murr
Sound and Lighting Supervisor
Arts Center at College of DuPage
Voice: 630-942-4215
Fax: 630-790-9806
Email: murrro@cod.edu
http://www.cod.edu/artscntr/

I would put good money on this being an airflow problem. Vaccuum your filters - if it keeps happening, contact your local support!

US:    +1 608-831-4116
UK:    +44 (0)20 8896 1000 

They are rental tour racks. Data is a hard line daisy chain from ISO Splitter to the racks. The racks are on their own run. Power is from the same source a combine of two 200amp main feeds. The 96 is the older CEM. The 24 I think is an older one. I am more familiar with Strand racks.It isn't an emergency it is just annoying. I clean this every three weeks.

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Mick

First, to directly answer part of your question, the SCR (power cube) typically fails on. That is not likely the problem you have encountered. You will want to eliminate a couple things before we shotgun probable issues at you.

 Here is a quick guide to ruling out the various components of the system.

• Incoming control-VS- problem at the rack
• Unplug DMX when this problem exists. (CEM+ will hold the current look for 180 seconds)  Does the flicker freeze continue at current level?
• If yes, the problem is the incoming connection/control
• Troubleshoot DMX cable. DMX cables frequently become problematic after years of problem free use.  Attempt a new/known good cable.
• Troubleshoot at control desk by changing to another DMX output if possible.  Caution: make sure patch and output setup for second port is consistant with first output.  This action is specific to the console type, so we cannot provide all instructions generically.
• If any devices such as splitters/mergers are in direct path between control console and dimming rack, remove them to see if anything changes.
• If no, the problem is in the rack.
• Set rack dimmers to a level at the CEM. Look at green output signals while lights flicker.
•  Case
• All green LED's clicker together = watch face panel for any error messages (suspect Airflow messages)
• Only some green LED's flicker on dimmers between CEM and dimmer module (suspect internal connection issues)
• LED remains solid on the output of the dimmers that are flickering (suspect a connection/lamp issue between dimmer and lamp in fixture(s) or also possibly shared neutral with poor conenction)
• Lights flicker on and off for dimmers that are supposed to be off AND the LED's of those dimmers do not come on.  (Short circuits in load wires are causing problems.)

Luke's suggestion of the airflow sensor is a very common scenario. If it is possible to watch the display during this problem, you will be able to quickly determine where the source of the problem.   As suggested by others here at ETC, we are happy to guide you through over the phone and can call you if you would prefer. Our US number is +1(608)831-4116, or you can email my directly at jdunnum@etcconnect.com if you would like to drop your local phone number to us.