DMX out from ETC wall jack panels?

[austio]

I have been a long-time browser of Control Booth forums, and always learn something new to use in my shows.

But today I need help.

I have an ETC wall panel with "Console Input" "RFU" & "ETCNet" (NOTE: it is called ETCnet1 now...)

I need to get a DMX signal out of this panel. Is that possible? The reason is, the panel is located on the stage wing, so it is the nearest most logical place to plug in a DMX controlled fixture I want to use. My console is plugged in BOH, but only uses "Console Input" on its panel.

The venue was originally wired with ETC stuff and an Expression 24/48, and had an RFU, all of which plugged into the three jacks. However, they now use an ETC Element. Someone recommended it as an "upgrade" for use with newer DMX controlled fixtures and LED lighting (venue has none), failing to notice that there are NO (zero, none, nada) DMX outputs anywhere else in the venue, so unless it is possible to get DMX from the 3 jacks mentioned above, I will need to run lots of extra wire.

Any thoughts?

 

[derekleffew]

You can use a gender changer to tap off that connection if you wanted to, those pins become live with DMX when DMX is fed into the system from the board. ...

Just because one CAN, doesn't mean on SHOULD.

Problem: I was installing them today. And well, it was a mis-read. DMX INPUT not OUTPUT. So I can hook up a board from backstage but I cant run annything with DMX without running a new cable.

The gender of the panel-mount connector should have been your first clue. With DMX, "the male always goes home," home being the console. Likewise, "females have all the power, and males always want the power."

The building is likely wired one of three ways:
1) Booth DMX Input goes to dimmers' DMX Input A and Stage DMX Input goes to dimmers' DMX Input B, and dimmers are set to take either or both on an HTP basis. This is the only "proper" wiring, but means that the Stage Input cannot be used as an output.
2) The Booth DMX Input loops through the Stage DMX Input, then onto the dimmers.
3) The Booth DMX Input and the Stage DMX Input are both homerun to the dimmers, where they are two-fered on the same dimmer input.
Both 2&3 are incorrect, but you could, with an A5F-A5F turnaround or cable, use the Stage Input as an Output. IF you're going to do this, it IS STRONGLY ADVISED that you use an opto-isolator immediately after the Stage "output."

If scenario#2 above (the most likely), once one changes the input into an output, one has created a Y-cable split. From Doug Fleenor Design - DMX Primer :

Splitting

Never split a DMX signal with a "wye" cable. Use a splitter device that buffers each line separately or daisy chain from device to device.

The problem with splitting the signal with a wye cable is that the signal going up one leg of the wye is reflected back down and corrupts the signal going down the other leg. The longer the legs of the wye, the worse the problem. A wye where each leg is 10 feet may work fine but may fail if the legs are increased to 100 feet. A lot has to do with the quality of the cable, the strength of the signal at the wye point, and your relationship with God.

Always better to run a long cable from output#2 on the console, to the DMX devices.

The building is likely wired one of three ways:
1) Booth DMX Input goes to dimmers' DMX Input A and Stage DMX Input goes to dimmers' DMX Input B, and dimmers are set to take either or both on an HTP basis. This is the only "proper" wiring, but means that the Stage Input cannot be used as an output.
2) The Booth DMX Input loops through the Stage DMX Input, then onto the dimmers.
3) The Booth DMX Input and the Stage DMX Input are both homerun to the dimmers, where they are two-fered on the same dimmer input.

Probably #2. A quick call to ETC Tech Services at 1-800-688-4116 and they can look up your job number and confirm how your building was wired.

 

[SteveB]

I have been a long-time browser of Control Booth forums, and always learn something new to use in my shows.

But today I need help.

I have an ETC wall panel with "Console Input" "RFU" & "ETCNet" (NOTE: it is called ETCnet1 now...)

I need to get a DMX signal out of this panel. Is that possible? The reason is, the panel is located on the stage wing, so it is the nearest most logical place to plug in a DMX controlled fixture I want to use. My console is plugged in BOH, but only uses "Console Input" on its panel.

The venue was originally wired with ETC stuff and an Expression 24/48, and had an RFU, all of which plugged into the three jacks. However, they now use an ETC Element. Someone recommended it as an "upgrade" for use with newer DMX controlled fixtures and LED lighting (venue has none), failing to notice that there are NO (zero, none, nada) DMX outputs anywhere else in the venue, so unless it is possible to get DMX from the 3 jacks mentioned above, I will need to run lots of extra wire.

Any thoughts?

Sounds like the stage box has a chassis mount male 5 pin XLR (console input), a 6 pin XLR - maybe chassis mount male ? (RFU), and either a Cat5 connector or a BNC connector for the ETC Net1.

From that configuration I would assume the 5 pin XLR for console connection would allow a local console to send DMX only to the dimmer rack, possibly on the B DMX connections in the dimmer rack(s). I would then also assume the 6 pin and the Cat5/BNC to run to a similar box in the booth where they would have hooked up to the console.

If the ETC Net is Cat5, you can get adapters to 5 pin XLR to get a DMX output off the Element at that stage jack location. If not Cat5 and it's a BNC, you might be able to get adapters made from 6 pin RFU to 5 pin XLR's to allow DMX to use the RFU cable - which I believe is DMX compliant. Best option would be to change out the 6 pin connectors to 5.

I'd be calling Steve Short at LiteTrol Service. If you e-mail him pictures of the boxes he can advise and figure out the best solution.

http://www.litetrol.com/

 

[derekleffew]

you might be able to get adapters made from 6 pin RFU to 5 pin XLR's to allow DMX to use the RFU cable - which I believe is DMX compliant. Best option would be to change out the 6 pin connectors to 5.

@SteveB, thank you. I always forget about using the RFU wiring for DMX512 porpoises!

If the wire was pulled according to ETC Spec (Belden 9728 or approved equal), the only difference with the RFU cable would be the extra set of conductors and shielding. Technically, RFU uses the same type of underlying data protocol (RS-485) that DMX uses, so data transmission down the pairs would not be a problem.

Changing the RFU's XLR6 s to XLR5 s is the best solution.
-----
Minor niggle:

... and an Expression 24/48, and had an RFU, ...

'Taint no such animal as "Expression 24/48"; you mean an Express 24/48.

 

[jfremm]

Hello everyone,

This question may not make sense and I apologize in advance, but I am really looking for some help. In our auditorium, we have a DMX input(male pins) in one of our wings. My question to you all is if you think the purpose of that input is for a light board, or if I could use it for a fixture I want to hang. I'm not really sure where to go with regards to this question, but perhaps other technicians might have a plausible answer.

Basically, we are looking at upgrading our current cycle to the Altman Spectra Series LED fixtures. I was wondering what the best way to run this back to our board would be. I figured if this DMX input worked, if at possible, just use that which connects to our board (I think).

Thank you

 

[Les]

A DMX input is for a console or RFU. What you need is a DMX output.

You could possibly turn the input in to an output by changing the connector to female and re-routing the other end, but it all depends on how your system is wired.

The other options are to A). put an opto-splitter and the booth and run a separate DMX line to the stage or B). Tap off the DMX in your dimmer rack which may require surgery and is best left to qualified personnel.

 

[SteveB]

Hello everyone,

This question may not make sense and I apologize in advance, but I am really looking for some help. In our auditorium, we have a DMX input(male pins) in one of our wings. My question to you all is if you think the purpose of that input is for a light board, or if I could use it for a fixture I want to hang. I'm not really sure where to go with regards to this question, but perhaps other technicians might have a plausible answer.

Basically, we are looking at upgrading our current cycle to the Altman Spectra Series LED fixtures. I was wondering what the best way to run this back to our board would be. I figured if this DMX input worked, if at possible, just use that which connects to our board (I think).

Thank you

I'm guessing, but and most of the time, the purpose of an additional input jack located other then the booth, is to allow a visiting or house console to activate the dimmers from the "other then booth" location. As such the wiring usually goes to the dimmers. If an ETC Sensor system, there's a "B" input to the dimming system for this 2nd DMX signal and I would suspect that's what your Input connection does. One clue is the male chasis connector being typical of a connection designed to receive a DMX signal from a console.

No way to really know unless you have access to the installation wiring plans. Or you can hookup a console and see if it activates dimmers, but I'd rather see the plans first.

One solution and I'd check with ETC, is if this connection port is indeed on the DMX B port of the dimmers would be to have this changed at the very first dimmer rack to land on the A port, which would then route the booth console signal to the dimmers and back this connection. Then change the connector to a chassis female 5 pin. I believed you are "allowed" one pass thru of this type without issue.

 

[RickR]

A vote for calling ETC, and some warnings!

Their drawings are how it was designed and only sometimes updated to 'as built'. Then life happens to the building and things get really interesting. Before making any wiring changes (especially in a school) someone should trace out the actual wires.

I have had bad luck converting RFU wiring to DMX. Yes the wire should work, but there are often many more input locations. They are also wired 'touch-n-go' which is not to the DMX/RS485 standard. There may be other issues but I suspect it would take a fair bit of detective work and an oscilloscope to sort out.

In another post I detailed using the second pair of the base DMX runs. This too is off the standard if only in philosophy, but it does classify as "future use"

 

[austio]

My original post had a few mistakes, as some of you noticed. First off, it was not ETCnet, it was ETCLink.

Sounds like the stage box has a chassis mount male 5 pin XLR (console input), a 6 pin XLR - maybe chassis mount male ? (RFU), and either a Cat5 connector or a BNC connector for the ETC Net1.

But the Steve was right on the rest of the box.

Probably #2. A quick call to ETC Tech Services at 1-800-688-4116 and they can look up your job number and confirm how your building was wired.

I called ETC, and was confirmed that the console input on the box could not be used. However, I was wondering about your description of possible wiring schemes, and took the box off the wall, and saw that it is a chain from another jack in the house, so DMX does flow through Console In, but putting that to a daisy chain to get DMX out would be a huge pain, though not impossible. It would also make for a very large worrisome daisy-chain before it gets to the main Unison/Sensor dimmer system that I would not like to deal with.

Changing the RFU's XLR6 s to XLR5 s is the best solution.

Thank you for this insight. I thought about this, but was wondering; would I then loose the ability to use the RFU, or does the RFU only work with the retired Express, and therefor its functionality is already gone (cannot be used with Element)? There are multiple RFU locations, as well (more than Console or ETCnet jacks), so converting these for DMX might be the ticket, as you suggest. In such a situation, is the DMX signal coming from the Unison system (as the Element is already sending DMX to that), or would I need to be plugging the re-purposed RFU line into the DMX output on the back of the Element?

'Taint no such animal as "Expression 24/48"; you mean an Express 24/48.

You are right.

I have actually purchased some wireless DMX units, and I will just use the second universe on the Element, but the venue (and I) will need a more permanent and robust setup in the future, so I will keep this thread handy.

I know this was in response to the other person's question on my thread, but it pertains to me as well I think... I have no idea what wired 'touch-n-go" means...?

 

[lightman02]

My original post had a few mistakes, as some of you noticed. First off, it was not ETCnet, it was ETCLink.



But the Steve was right on the rest of the box.



I called ETC, and was confirmed that the console input on the box could not be used. However, I was wondering about your description of possible wiring schemes, and took the box off the wall, and saw that it is a chain from another jack in the house, so DMX does flow through Console In, but putting that to a daisy chain to get DMX out would be a huge pain, though not impossible. It would also make for a very large worrisome daisy-chain before it gets to the main Unison/Sensor dimmer system that I would not like to deal with.



Thank you for this insight. I thought about this, but was wondering; would I then loose the ability to use the RFU, or does the RFU only work with the retired Express, and therefor its functionality is already gone (cannot be used with Element)? There are multiple RFU locations, as well (more than Console or ETCnet jacks), so converting these for DMX might be the ticket, as you suggest. In such a situation, is the DMX signal coming from the Unison system (as the Element is already sending DMX to that), or would I need to be plugging the re-purposed RFU line into the DMX output on the back of the Element?



You are right.

I have actually purchased some wireless DMX units, and I will just use the second universe on the Element, but the venue (and I) will need a more permanent and robust setup in the future, so I will keep this thread handy.

I know this was in response to the other person's question on my thread, but it pertains to me as well I think... I have no idea what wired 'touch-n-go" means...?

You can use the DMX input port on the box as an output when you are feeding DMX from one of the other existing ports such as the booth by using a gender changer as I stated before. It's all on the same data bus and there is no issue when using it that way and if ETC is telling you no, then I'm sorry they are misleading you. It's thesame is if you were daisy chaining fixtures, the only difference is the gender in this case. If you do decide to use that port as an output and have a lot of DMX fixture off that line then go into an OPTO from there. As long as that port is on the same side as your control console it will work.

 

[robartsd]

You can use the DMX input port on the box as an output when you are feeding DMX from one of the other existing ports such as the booth by using a gender changer as I stated before. It's all on the same data bus and there is no issue when using it that way and if ETC is telling you no, then I'm sorry they are misleading you. It's thesame is if you were daisy chaining fixtures, the only difference is the gender in this case. If you do decide to use that port as an output and have a lot of DMX fixture off that line then go into an OPTO from there. As long as that port is on the same side as your control console it will work.

I'm guessing that ETC is telling him no because the project information they have shows that this would not work because either 1) it would create a Y in the DMX because this port is between the booth and the dimmers (may work with possible reliability issues) or 2) this port goes to a secondary input on the dimmers and does not see the booth output (will not work at all).

 

[lightman02]

Well like I was saying, it has to be on the same port, most I have seen are. As far as a Y split, you are not creating a Y split, you are actually treating the dimmers as sort of a fixture that you would daisy chain out of, it the same wiring path flow wise.

 

[robartsd]

Thank you for this insight. I thought about this, but was wondering; would I then loose the ability to use the RFU, or does the RFU only work with the retired Express, and therefor its functionality is already gone (cannot be used with Element)? There are multiple RFU locations, as well (more than Console or ETCnet jacks), so converting these for DMX might be the ticket, as you suggest. In such a situation, is the DMX signal coming from the Unison system (as the Element is already sending DMX to that), or would I need to be plugging the re-purposed RFU line into the DMX output on the back of the Element?

The RFU port was for a wired remote for the Express. The Element does not use this remote, so the wiring could be repurposed without a loss of functionality. The Element supports network, USB, and phone remotes. As you've stated that there are many RFU ports, you'll want to make sure that your reuse of the wiring does not create problematic topography for your DMX signal.

 

[DavidNorth]

I'm guessing that ETC is telling him no because the project information they have shows that this would not work because either 1) it would create a Y in the DMX because this port is between the booth and the dimmers (may work with possible reliability issues) or 2) this port goes to a secondary input on the dimmers and does not see the booth output (will not work at all).

Well like I was saying, it has to be on the same port, most I have seen are. As far as a Y split, you are not creating a Y split, you are actually treating the dimmers as sort of a fixture that you would daisy chain out of, it the same wiring path flow wise.

It was very common, when those system were designed, to have DMX Input jacks daisy-chained through the facility on the way to the dimmer racks. This is what creates the moniker, "touch and go." What we did was take DMX from the booth Input, run the wire to the next DMX Input jack [touch], and then run the wire [go] to the next DMX Input jack, and so on, until we reached the dimmer racks. The reason we did this is because users wanted the ability to plug the console in at various places in the building [booth, FOH, backstage] depending on what they wanted to do for their show. This means that there was only ever one DMX source and then DMX racks on the other end without a plan for other uses. The notion of having DMX Outputs around the building only became prevalent after DMX scrollers and moving lights came in to popularity.

So yes, in this wiring scenario, you would indeed create a "Y" if an Input was used as an output, however, you would be ok if you placed a splitter or booster right at the Input being used as an Output every time you want to use that data. If the dimmers were in the middle of the wiring run, instead of the end, then you would not have a "Y" situation. This one is a "Y". Use a splitter/booster or don't use the Input as an Output, please, as you could end up with corrupted data and loss of control.

Yes, the RFU wiring could indeed be reused as another data run given installation of the correct connectors. Do be warned that this is also a "touch and go," which means you could use one Input and one Output only, unless of course each Output also utilized a splitter/booster.

Later ETC systems did use splitters and data homeruns to distribute DMX throughout a space until network solutions took over.

David

 

[lightman02]

David, I was assuming that the connections were terminated at the dimmer itself and not intercepted in the middle of the data run. But you do agree that and input is not always have to be used as an input and can be output under certain situations which is my point. However if you look up schematics of how dimmers and fixtures pass dmx u will see where I'm coming from. Also DMX really doesn't have an in and out.

 

[SteveB]

Well, and as a quibble, DMX does indeed have and in and out. The out would be the transmitting device and would have a female 5 pin XLR connector on the transmitting source. The "in" is of course at the receiving device(s), which would have male XLR 5pin (one hopes).

The fact of this is why we were able to ascertain from the OP description that the chassis mounted male connectors in a stage located box, were likely to be additional input locations for additional consoles (the touch and go system that DN describes). Had it been a female connector, it would have probably been a DMX send port from a DMX source - booth control ?, splitters somewhere ?.

And as described in posts above, certainly the input connections "could" be re-purposed, but as they in this scenario probably don't go back to the booth, re-purposing as an output from a booth located console isn't going to work, as the existing DMX cable might well be the only connection from the booth console to the dimmers. Thus a recommendation to maybe re-use the Link cable, having disconnected it at the dimmers with appropriate 5 to 6 pin adapters.

 

[lightman02]

Dmx is transmitted from the board it's then looped through every dimmer, mover, fog machine, etc. It is not retransmitted from device to device with an opto being an exception to this rule.
This is why dmx still passes even when your dmx devices are unplugged from their power source. As I stated DMX does not have an in and out really it has transmit and receive only. The console being the transmitter.

 

[DavidNorth]

Dmx is transmitted from the board it's then looped through every dimmer, mover, fog machine, etc. It is not retransmitted from device to device with an opto being an exception to this rule.
This is why dmx still passes even when your dmx devices are unplugged from their power source. As I stated DMX does not have an in and out really it has transmit and receive only. The console being the transmitter.

Well, it's not always true that the DMX In and Out are the same on DMX products. It does indeed depend on how they are designed, and yes, I have looked at many schematics. [My degree is in electrical engineering and I have done product repair and support for several decades. ]

Since some products do receive DMX and then retransmit a new DMX stream as an output, I am making a general statement that an In is an In and Out is an Out. Technically, an In is tied to a Pass Through and an Out is a transmitted DMX signal. it is unfortunately very common that we interchange the terms DMX Out and DMX Pass Through when they are not the same thing. Thomas I think you mean to use Pass Through.

So, to do some fun ASCII graphics, since I don't have time to sketch today.....here's the system the OP posted.

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]

If he was to patch a DMX cable into the backstage DMX In jack, he will have a "Y" as seen here:

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|- - - - - [LED] - - - - - - - - - [LED]

You can in fact cheat, but you have to use turnarounds and you have to always use a splitter or booster and do this:

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]
--------------------------------------------------------------------------------------------|
----------------------------------------------------------------------------------[Splitter/Booster]
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|- - - - - [LED] - - - - - - - - - [LED]

But, that splitter or booster needs to be at the jack. Steve has the cleaner solution to reuse the now unused ETCLink cabling. Better yet, get a technician in there that knows how to correctly reuse the wiring and install new connectors, and then this is a system that will always work no matter who uses it in the future. Isn't that what we should really be looking for?

David

 

[SteveB]

This is why dmx still passes even when your dmx devices are unplugged from their power source. .

With an opto again being an exception to the rule.

 

[lightman02]

Well, it's not always true that the DMX In and Out are the same on DMX products. It does indeed depend on how they are designed, and yes, I have looked at many schematics. [My degree is in electrical engineering and I have done product repair and support for several decades. ]

Since some products do receive DMX and then retransmit a new DMX stream as an output, I am making a general statement that an In is an In and Out is an Out. Technically, an In is tied to a Pass Through and an Out is a transmitted DMX signal. it is unfortunately very common that we interchange the terms DMX Out and DMX Pass Through when they are not the same thing. Thomas I think you mean to use Pass Through.

So, to do some fun ASCII graphics, since I don't have time to sketch today.....here's the system the OP posted.

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]

If he was to patch a DMX cable into the backstage DMX In jack, he will have a "Y" as seen here:

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|- - - - - [LED] - - - - - - - - - [LED]

You can in fact cheat, but you have to use turnarounds and you have to always use a splitter or booster and do this:

[Console] - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - [DMX In] - - - - - - - - - - - - - - - [Dimmers]
--------------------------------------------------------------------------------------------|
----------------------------------------------------------------------------------[Splitter/Booster]
--------------------------------------------------------------------------------------------|
--------------------------------------------------------------------------------------------|- - - - - [LED] - - - - - - - - - [LED]

But, that splitter or booster needs to be at the jack. Steve has the cleaner solution to reuse the now unused ETCLink cabling. Better yet, get a technician in there that knows how to correctly reuse the wiring and install new connectors, and then this is a system that will always work no matter who uses it in the future. Isn't that what we should really be looking for?

David

It's like I said the port is part of the same data bus as long as it was wired properly even though it is labeled as input it can be used to carry the same data signal to another device and you should use an OPTO as the cable length from the transmitter is