Automated Fixtures Dimmer Racks with Moving Lights

[sk8rsdad]

I have one ETC Sensor ThruPower module but I have a CEM+ rack so it sucks that I can't use it to it's full advantage. The problem I was trying to solve was to provide a single FOH relay circuit for a pair of MLs. I can't justify the CEM3 upgrade for the sake of one circuit. It's more convenient to run an extension cord to one of the domestic power receptacles.

To be fair, I misunderstood the documentation. I knew I wouldn't be able to reconfigure it "on the fly" but I thought I would be able to configure it in the rack with one half as a D20 and the other as an R20, or maybe some magic combination so that when configured as Full at 50%/Switched/Unregulated it would use the relay instead of the the SCR. Instead it's just an expensive CC20 module. Maybe with enough market pressure ETC might publish an update to the CEM+ firmware.

 

[derekleffew]

But one can, lacking Sensor3 backplane, at the rack, configure one side as a D20 and the other as a CC20, yes?

... Maybe with enough market pressure ETC might publish an update to the CEM+ firmware.

I may well be wrong, but I thought it required more than a firmware update. I thought more wires needed to be run to the "control" portion of the module for full functionality?

 

[sk8rsdad]

I thought more wires needed to be run to the "control" portion of the module for full functionality?

The upgrade manual shows changing out the backplane and optionally changing out the AF cards (I don't have an AF rack) but there is no indication that the existing wiring harnesses need to be replaced.

But one can, lacking Sensor3 backplane, at the rack, configure one side as a D20 and the other as a CC20, yes?

One can push a button on the face of the ThruPower to turn one or both dimmers into a CC. It is inconvenient and/or electrically inefficient to do so because it means a trip to the dimmer closet to energize/de-energize the circuit. Not terribly useful if you either don't have access to the dimmer closet or it is off the beaten path and likely to be forgotten. For every other circuit in the house I can power down the console and after the 3 minute delay on "hold last look" all the MLs, scrollers, LEDs, foggers, and hazers are powered off.

So for me the TP20 is really not that useful. I would have been better off with an R20 and a shoebox dimmer.

 

[SteveB]

The upgrade manual shows changing out the backplane and optionally changing out the AF cards (I don't have an AF rack) but there is no indication that the existing wiring harnesses need to be replaced.


One can push a button on the face of the ThruPower to turn one or both dimmers into a CC. It is inconvenient and/or electrically inefficient to do so because it means a trip to the dimmer closet to energize/de-energize the circuit. Not terribly useful if you either don't have access to the dimmer closet or it is off the beaten path and likely to be forgotten. For every other circuit in the house I can power down the console and after the 3 minute delay on "hold last look" all the MLs, scrollers, LEDs, foggers, and hazers are powered off.

So for me the TP20 is really not that useful. I would have been better off with an R20 and a shoebox dimmer.

If you need to swap a dimmed circuit to a relay or constant, you are hiking up/down to the dimmer closet anyway - Yes ?, in this case you are merely pushing a button. As well, less logistics involved when you figure the plot out to know you only lose one dimmer, not 2.

But I could see where this is not cost effective unless you are doing a bunch of constantly swapping circuits as well as making the rack CEM3 so as to do the switch from the console.

 

[sk8rsdad]

If you need to swap a dimmed circuit to a relay or constant, you are hiking up/down to the dimmer closet anyway - Yes ?

I guess I'm not explaining the situation well.

I need one unregulated, unswitched circuit in the FOH. I don't plan on swapping things around and really didn't want to lose the other dimmed circuit. There is no plan to swap things around regularly. One half of the TP20 powers a pair of rehearsal worklights. The other half powers the DMX splitters and was supposed to be used for the 2 MLs.

As a CC20, every day requires at least 2 trips to the dimmer closet to energize and then de-energize the circuit. It is more convenient to unplug the MLs on the way down from the booth than it is to go downstairs to the dimmer closet, unlock the rack door and push the button.

If the TP20 could be configured to work as either a D20 or R20 or better yet, any combination of D20/R20 it would be wa-a-a-a-y more useful. As it is today, with a CEM+ it can only be used as a D20 and/or a manually switched CC20. Today the only way to get a TP20 to behave like an R20 is to upgrade the CEM+ to a CEM3. That won't be free. Also, the field tech that is required to do the upgrade needs to be flown in from Toronto at my expense.

I should have bought an R20 and lived with the loss of dimming of the rehearsal worklights. I just can't get what I want from a TP20 without a much more expensive rack upgrade.

 

[SteveB]

You are basically saying that the Power-Thru module, in a CEM+ rack, when one half is set to be a relay, that half does not respond to DMX control and can only be powered down in a similar fashion as a constant breaker ?.

That makes no sense if true.

I thought the only add'l function that CEM3 gave you was the ability to configure the module to either dimmed, or relay from the console.

I think I'm missing something.





Sent from my iPad using Tapatalk

 

[sk8rsdad]

You are basically saying that the Power-Thru module, in a CEM+ rack, when one half is set to be a relay, that half does not respond to DMX control and can only be powered down in a similar fashion as a constant breaker ?

Bingo!!!

In a CEM+ rack, a TP20 is either a D20 or an expensive CC20. There is no DMX, ACN, EDMX, or any other remote control that would allow it to be used as a relay. I personally think it is a huge design miss on ETC's part.

 

[DavidNorth]

I personally think it is a huge design miss on ETC's part.

I would say more a limitation than a design miss. Ok, so maybe a design miss, but when we designed the CEM+ control module over 10 years ago, we never anticipated it doing all the things that CEM3 now needs to do, including running the TP20 modules. We ran out of horsepower and software space to be able to do this work, so we moved on to CEM3. At least there is an upgrade path, which is not always available in other products [ie Unison].

To answer some other questions above....it is not a new wiring harness or other hardware that has to be installed to run the TP20 modules when do an upgrade. It is specifically a backplane change and the CEM3. The rest of the trick is software in the CEM3 and some software in the TP20. It's quite an elegant solution [more elegant than the datasheet copy writing] and does allow all racks made since their inception in 1992 to be able to take both the CEM3 and TP20s without any additional mods.

sk8rsdad, please let me know what led you to believe that the TP20 would work with the CEM+. If we've made some other copy error, I'd like to fix it. Maybe even someone told you incorrectly. I know that at tradeshows, and other places, I have said that it would work in any Sensor rack as a dimmer or contact module but only with CEM3 do you get all the other features.

Other questions?

David

 

[sk8rsdad]

Thanks David.

If you can dig up the incident report on [300314729], Kirk and I exchanged a few e-mails about it. I was confused by the datasheet:

I knew I wouldn't be able to reconfigure on the fly but thought I would be able to program the mode in the rack. Any chance of that coming as a patch to CEM+?

Maybe the data sheet should be amended to expain the limitations for CEM/CEM+ owners. As it reads now it states:

"the thruPower module supports circuit-specific setup and load feedback that can be accessed remotely with any ACN control system"​

Well, I have an ACN control system and apparently it can't do circuit-specific setup, or if it can, it is undocumented.

I'm sure you don't really want to discuss design issues on a public form but I assume you are sending some sort of magic serial packet to the TP20 to turn on the relay. Is there really no headroom in the firmware to allow that packet to be sent for some combination of configuration of the module?

 

[DavidNorth]

Thanks David.

If you can dig up the incident report on [300314729], Kirk and I exchanged a few e-mails about it. I was confused by the datasheet:

I'm sure you don't really want to discuss design issues on a public form but I assume you are sending some sort of magic serial packet to the TP20 to turn on the relay. Is there really no headroom in the firmware to allow that packet to be sent for some combination of configuration of the module?

Good info! Yes, I could see where that's confusing. I look into it some more.

So yes, we do send a magic serial packet, but not to configure it - to fire it. The control module has to do the heavy lifting of processing. I'm not really giving any secrets away with that as serial is such an overly broad term. Since there are so many parameters that can be controlled within the module, that all has to be done live, or we would have to up the processing capability within the module and change the data bus to the module. Of course, then each module would be much more expensive and rack ugrades to CEM3 would go up dramatically - most notably on the technicians installation labor side of things.

You guys ask such good questions and get more out of me each time.....

David

 

[derekleffew]

Sorry, another hijack...
BTW, Mr. North, congrats on your new promotion(?)/position. I tried to meet you at LDI but you were always tied up giving demonstrations. You maybe should update your title and profile page here to reflect your new status.

 

[DavidNorth]

Thank you. Yes, a promotion and new position, but I'll still be on here as always. I might just talk a little more about rigging from time to time.

Sorry I missed you as well. I did run into dvsDave, and I think I saw gafftaper. I hope I can join the CB fun at LDI next year.

Profile page updated.

Now, back to the thread....

David