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Title: 2 DMX lines using 5 pin
Post by: Daniel Nickleski on November 15, 2007, 02:36:50 PM
Hello All,
 I don't know if this is possible, but here it goes. I am sending two DMX line to the stage (1 for conventional, 1 for Movers) all of which are 3 pin. Would I be able to send these two lines down a 5 pin DMX cable. I know I would have to make a custom (2) 3 pin male to 5 pin converter for FOH and a 5pin to (2) 3 pin female for the stage. Would I be able to share the shield for the two separate signals and then use the remaining 4 conductors for my Data + and -. I hope this question is making sense.
 Thanks for any help!
    Daniel
Title: Re: 2 DMX lines using 5 pin
Post by: Tony "T" Tissot on November 15, 2007, 03:40:35 PM
The question makes sense.

From a practical POV - this works. I have done it in the past.

The only real issue is potential cross talk. Make sure both runs get terminated.
Title: Re: 2 DMX lines using 5 pin
Post by: John Birchman, CTS on November 15, 2007, 05:11:44 PM
Yes - the 5 pin protocol is set up for this:

1. Data Link Common
2. Data 1- (Primary Data Link)
3. Data 1+ (Primary Data Link)
4. Data 2- (Secondary Data Link)
5. Data 2+ (Secondary Data Link)

They both share the common on pin 1, again, just make sure to terminate both data sets and the end of each chain.

John
Title: Re: 2 DMX lines using 5 pin
Post by: len woelfel on November 16, 2007, 07:44:19 AM
Never done it, but considering the cost of cable versus the potential for aggravation if you run into a problem, I'd rather just run a second cable.  
Title: Re: 2 DMX lines using 5 pin
Post by: Emil Barnabas on November 17, 2007, 11:47:42 PM
Make sure your five-pin cable has five conductors running through it. I've seen three-conductor cable sold with five-pin connectors because most people only need the first three conductors.

If you have five-conductor cable, then it should work fine.
Title: Re: 2 DMX lines using 5 pin
Post by: David Buckley on December 09, 2007, 10:33:01 PM
Some desks (Like pearls) are set up to do exactly this, two universes down one cable.
Title: Re: 2 DMX lines using 5 pin
Post by: Randy Pence on December 17, 2007, 08:19:23 PM
len woelfel wrote on Fri, 16 November 2007 13:44

Never done it, but considering the cost of cable versus the potential for aggravation if you run into a problem, I'd rather just run a second cable.  


what about the labor costs of running a second cable?
Title: Re: 2 DMX lines using 5 pin
Post by: Phil LaDue on December 17, 2007, 09:25:32 PM
Randy Pence wrote on Mon, 17 December 2007 20:19

len woelfel wrote on Fri, 16 November 2007 13:44

Never done it, but considering the cost of cable versus the potential for aggravation if you run into a problem, I'd rather just run a second cable.  


what about the labor costs of running a second cable?


Have the FNG bundle them together at the shop before the load in.
Title: Re: 2 DMX lines using 5 pin
Post by: Blair Willis on January 04, 2008, 10:53:18 PM
To further complicate the question:

Would there be any problem using opposing signal directions?  That is, could one twisted pair be used for an upstream signal, the other for a downstream signal?

Thanks for your input (and output),

Blair




Title: Re: 2 DMX lines using 5 pin
Post by: Ron Hebbard on January 05, 2008, 04:24:34 AM
Blair Willis wrote on Sat, 05 January 2008 03:53

To further complicate the question:

Would there be any problem using opposing signal directions?  That is, could one twisted pair be used for an upstream signal, the other for a downstream signal?

Thanks for your input (and output),

Blair




Hello Blair;

I believe this has already been done by some of the higher end manufacturers with one pair carrying control info from a console to it's dimmers, foggers, scrollers, 'wigglies', et al and the secondary pair carrying report info back to the console for things such as load changes, fan failures, over-temp, etcetera.

Toodleoo!
Ron Hebbard
Title: Re: 2 DMX lines using 5 pin
Post by: len woelfel on January 06, 2008, 11:16:56 AM
Ron Hebbard wrote on Sat, 05 January 2008 03:24

Blair Willis wrote on Sat, 05 January 2008 03:53

To further complicate the question:

Would there be any problem using opposing signal directions?  That is, could one twisted pair be used for an upstream signal, the other for a downstream signal?

Thanks for your input (and output),

Blair




Hello Blair;

I believe this has already been done by some of the higher end manufacturers with one pair carrying control info from a console to it's dimmers, foggers, scrollers, 'wigglies', et al and the secondary pair carrying report info back to the console for things such as load changes, fan failures, over-temp, etcetera.

Toodleoo!
Ron Hebbard


Yes, the second pair was originally designed to carry fixture data back to the console.  Basically a feedback channel as you guessed.  
Title: Re: 2 DMX lines using 5 pin
Post by: Ron Hebbard on January 06, 2008, 12:01:48 PM
len woelfel wrote on Sun, 06 January 2008 16:16

Ron Hebbard wrote on Sat, 05 January 2008 03:24

Blair Willis wrote on Sat, 05 January 2008 03:53

To further complicate the question:

Would there be any problem using opposing signal directions?  That is, could one twisted pair be used for an upstream signal, the other for a downstream signal?

Thanks for your input (and output),

Blair




Hello Blair;

I believe this has already been done by some of the higher end manufacturers with one pair carrying control info from a console to it's dimmers, foggers, scrollers, 'wigglies', et al and the secondary pair carrying report info back to the console for things such as load changes, fan failures, over-temp, etcetera.

Toodleoo!
Ron Hebbard


Yes, the second pair was originally designed to carry fixture data back to the console.  Basically a feedback channel as you guessed.  



Hello Len and happy new year!

I wrote that "I believed", I don't recall indicating any guessing on my part. ;^)

Toodleoo!
Ron Hebbard