Ion DMX/dimmer communication issue

An update on the information:

(and I will be calling ETC this evening once the console is brought to the theatre for testing)

-the dimmers are a strand brand (but I do not know the make yet)

-the dimmers were reset to no effect

-the equivalent of an opto-splitter was used to no effect

-all the DMX outputs were tried.

I do not know how to find out if the dimmer racks are terminated, but I am hoping knowing the model will lead me to useful specs regarding this.

The only suggestion I was given from someone at the theatre to try is to try the patch bay on stage verses the patch bay in the booth to try to eliminate it as a board problem. As well I might be in touch with Solotech, the company we purchased it from, to try to borrow a DMXter (another suggestion from an electronics/DMX instructor).

And thank you both for your help and suggestions!

-

Christina S

National Theatre School of Canada, Monument National

I realize you are still developing information related to your problem- but I would have a few other questions to ask if I were the tech helping you.

Are you sending DMX from the console directly into the dimmer racks, or is it going into a Strand DMX node? 

Also, are there any other controls for these lights like a button station on the wall for houselight controls?

When the lights flash or flicker, do they all flash randomly like a disco or night club, or are they all pulsing on and off together in a slower pulse (i.e. lights on, 2-3second delay, lights off, 2-3 second delay lights on?)

Depending on the equipment you have, and the type of flashing/pulsing you are seeing, I might have some Strand related things you could check on.   This would especially apply if the rack is a C21 and the architectural system is Strand's Vision.net controls. If you have any Strand N21 DMX nodes in the system, that can also be related to this problem.  It might not be the ION that is the main problem, but the configuration of the Strand system.

Please let us know what you find if you manage to resolve the problem outside of the forum. 

Thanks.

The dimmers are Strand CD80 with a C21 processor.

Yes there is a mount on the wall for controlling the house lights manually that overrides board control when on.

The pulse is subtle and more or less together. I noticed it only at a low level where the level change was more obvious. Almost like candle light, if you will.

We did discover something very peculiar, however, which I will try to explain, that we believe cleaned up our DMX line/signal. We plug the console into a patch panel in the booth. This panel (along ith DMX 1 that goes to the dimmers) has DMX 3 input and output runs that goes to the stage and back. (DMX 2 doesnt work) Right now we had to set up the console while another production is going on so there are lights set up on stage, two of these being claypacky stagecolour 300s. Their current patch goes from the console to DMX 3 on the patch bay, to the stage, daisy chained through the movers, back to the stage, back to the booths patch panel, and from the output of DMX 3 to the input of DMX 1 to the dimmer rack. Somehow running all this before sending the Ion's signal to the dimmers stops the lights from reacting. We do not know, however, what specifically helped in this process.

We do not have more time in the theatre tonight to troubleshoot more but tomorrow night we hope to spend much more time testing the DMX run and other options as well as call tech support. If you have any more information or suggestions on tests to make please let me know!

Thank you so much for all your help.

That is a heck of a long path for the DMX.  Not knowing the Clay Paky's it might be that they are re-generating the signal, but I suspect not.  That being said, a long run of DMX can sometimes tame some signal goofiness.  It can sometimes also make it more present, as can either terminating or not terminating the DMX runs.  But that is not the issue here.

So if I understand your situation correctly, if you plug the ION directly in to DMX 1 to the dimmers, you get a slow pulsing.  When you make the cable path run from the booth to the stage, through 2 more devices (the clay pakys,) and back to the booth, then on to the C21 processor, the problem seems to get better?

Do you know if the DMX signal from DMX 1 lands directly on the dimmer rack DMX input?  Or does it pass through any other permanently wired devices in the chain (i.e. a VisionNet to DMX interface, a Premiere Architectural processor, or some other control system for the houselights?)

Is there a network setup for the Strand system for running Strand Shownet (sorry ETC I know it's your forum, but the problem I suspect is related to Strand configurations.)

If there is a network setup for the lighting, do you know if you have an N21 or SN110 nodes in the signal path?  If so, do those devices either receive DMX or send DMX to the dimmers on the same Strand NetSlots?  Depending on how the Strand Netslot rules are setup, you can have two devices on the network fighting for control (put the lights at 100, no put the lights at 0, no put the lights at 100,) causing a flashing problem that looks quite different from bad DMX or unterminated DMX. It isn't a reflection issue, but a fight for control.  This can usually be solved by giving each device listening to the DMX a different set of netslots.   An easy test is to disconnect the DMX wires from the C21 processor housing if you feel comfortable doing that, and letting the Shownet DMX node handle the console DMX input to the rack, all of this is provided you have a Strand Shownet network installed.   If you do have that, and disconnecting the rack DMX eliminates the slow pulsing, then I'd contact Strand Tech support in Dallas to pursue further remedies.  If not, then back to DMX terminations and wiring checks.

Another thought on the simpler DMX wiring checks, if you can take the patch panel plate in the booth off the wall  and check to see if both the Data - and Data + wires are landed on the connector terminations, that might be a good check.  I've seen the DMX wires come loose from these plates (both on ETC and Strand jobs,) when the wires either weren't inserted far enough into the pressure plates, or the screws weren't sufficiently tightened down.  This could give faulty DMX which is just solid enough for the rack to respond, but respond with the flickers you are seeing.  

Finally, as I don't know your skill level, please take this with the respect is being delivered with... If you need to open the dimmer panel or the patch panel plate, and there is 120VAC or higher present in that device (the dimmer will have that voltage available,) I highly recommend you shut the main power to that device down before opening up any panel.  This is meant to protect both the equipment, and more importantly, yourself from shock hazards.  If you don't feel capable or qualified to open up any of these panels, then by all means contact someone who is. 

Good luck.

That is a heck of a long path for the DMX.  Not knowing the Clay Paky's it might be that they are re-generating the signal, but I suspect not.  That being said, a long run of DMX can sometimes tame some signal goofiness.  It can sometimes also make it more present, as can either terminating or not terminating the DMX runs.  But that is not the issue here.

So if I understand your situation correctly, if you plug the ION directly in to DMX 1 to the dimmers, you get a slow pulsing.  When you make the cable path run from the booth to the stage, through 2 more devices (the clay pakys,) and back to the booth, then on to the C21 processor, the problem seems to get better?

Do you know if the DMX signal from DMX 1 lands directly on the dimmer rack DMX input?  Or does it pass through any other permanently wired devices in the chain (i.e. a VisionNet to DMX interface, a Premiere Architectural processor, or some other control system for the houselights?)

Is there a network setup for the Strand system for running Strand Shownet (sorry ETC I know it's your forum, but the problem I suspect is related to Strand configurations.)

If there is a network setup for the lighting, do you know if you have an N21 or SN110 nodes in the signal path?  If so, do those devices either receive DMX or send DMX to the dimmers on the same Strand NetSlots?  Depending on how the Strand Netslot rules are setup, you can have two devices on the network fighting for control (put the lights at 100, no put the lights at 0, no put the lights at 100,) causing a flashing problem that looks quite different from bad DMX or unterminated DMX. It isn't a reflection issue, but a fight for control.  This can usually be solved by giving each device listening to the DMX a different set of netslots.   An easy test is to disconnect the DMX wires from the C21 processor housing if you feel comfortable doing that, and letting the Shownet DMX node handle the console DMX input to the rack, all of this is provided you have a Strand Shownet network installed.   If you do have that, and disconnecting the rack DMX eliminates the slow pulsing, then I'd contact Strand Tech support in Dallas to pursue further remedies.  If not, then back to DMX terminations and wiring checks.

Another thought on the simpler DMX wiring checks, if you can take the patch panel plate in the booth off the wall  and check to see if both the Data - and Data + wires are landed on the connector terminations, that might be a good check.  I've seen the DMX wires come loose from these plates (both on ETC and Strand jobs,) when the wires either weren't inserted far enough into the pressure plates, or the screws weren't sufficiently tightened down.  This could give faulty DMX which is just solid enough for the rack to respond, but respond with the flickers you are seeing.  

Finally, as I don't know your skill level, please take this with the respect is being delivered with... If you need to open the dimmer panel or the patch panel plate, and there is 120VAC or higher present in that device (the dimmer will have that voltage available,) I highly recommend you shut the main power to that device down before opening up any panel.  This is meant to protect both the equipment, and more importantly, yourself from shock hazards.  If you don't feel capable or qualified to open up any of these panels, then by all means contact someone who is. 

Good luck.