Control/Dimming DMX 5 pin to 3 pin

[TheGuruat12]

Our Crew is strongly considering purchasing an Antari HZ-300 haze machine. It accepts a 3-pin xlr DMX connection for control by a lighting console. Patching it seems to be easy enough, but I have one problem with it.

We're running an Express 48/96 with one of the DMX universes (A) going to our dimmer racks. DMX B has data outputs in the sound booth, on the catwalk, and SL and SR. I believe (cannot be sure, will check next time I am in the auditorium) that the connectors on these outputs are 5-pin xlr.

My question is this: Can a simple 5-pin female to 3-pin male adapter be used with this haze machine? Or would we need some sort of specialized transformer/converter?

 

[derekleffew]

...My question is this: Can a simple 5-pin female to 3-pin male adapter be used with this haze machine? Or would we need some sort of specialized transformer/converter?

I believe you have it backwards. See the wiki entry adapter, 5-3. The male (be it 3pin or 5pin) is the data input, and the female the output. But yes, just an adapter, no transformer or converter required.

 

[mstaylor]

An adapter cable is very simple to make or you can buy already made if you don't trust your soldering skills.

 

[David Ashton]

If all your gear and leads are 5 pin then it really is worth changing the sockets on the machine as long as they are not hard connected onto a circuit board, the trouble with adaptors is that they get lost, just when you need them, I always have 10 3/5 adaptors in my van m/f and f/m because I deal with all mixtures of gear, but for your use a change-over to 5 pin would seem the most sensible pins 1,2,3 on each are the same.4 & 5 are empty.

 

[WooferHound]

A standard 5 pin DMX cable has 2 sets of Shielded Twisted Pair signal paths in it. One of them is the output data from the console to the lights and other devices that use it. The other signal path is intended to be Return Data to the console but it is rarely used and you generally don't need it so these connections don't need to be included in Adapter connections. Only a few devices are wired to send the data which might include: Dimmer or Fixture Temperature, Filter Clogged Information, Error Data and a few other parameters.

If you don't expect to ever use any equipment that sends any return data, then you can use a single DMX cable to send 2 Universes and make a Y configuration on each end of the cable using 2 connectors wired to each signal path.

 

[TheGuruat12]

Thanks guys!

Oh, and Derek, you are correct. I had the adapter backwards.

 

[Footer]

Only a few devices are wired to send the data which might include: Dimmer or Fixture Temperature, Filter Clogged Information, Error Data and a few other parameters.

What devices are those? I believe even RDM runs on top of the same pair that DMX does.

 

[derekleffew]

In my opinion, the issue of what to do with pins 4&5 is one area where the framers of DMX512 really screwed up. They chose the 5pin XLR over the 3pin specifically so people wouldn't/couldn't use mic cable, but never defined uses for the other two pins. Every revision has further restricted the use of the second data pair.

... If you don't expect to ever use any equipment that sends any return data, then you can use a single DMX cable to send 2 Universes and make a Y configuration on each end of the cable using 2 connectors wired to each signal path.

One can do that, and there are even commercial products to accommodate this use ( Data Products™ Cables & Adaptors: Universe Saver Adapter Set | Lex Products ), but it is specifically disallowed in ANSI E1.11 - 2008.
From another forum:

On an XLR connector, yes they could be but it is generally advised not to and the current ESTA standards have all removed the functionality of a 2nd universe on the XLR pins 4/5.

This is mostly due to the enormous minefield of incompatability. Other uses of pins 4/5 include, but are not limited to: power (BAD, BAD idea!), properietary protocols, don't exist (either aren't wired or dropped through 5 to 3pin adapters).

"Using the 2nd pair for another universe would fall within the requirement of Annex B."

Yes and no. There specifically is no EF# to declare unidirectional data on the 2nd pair (i.e. another universe of DMX). The 2nd pair is explicitly defined as being a bidirectional data link or return data link. Now technically if the 2nd universe had RDM on it too, then you might be able to claim it as EF3 or EF4 even though RDM is specifically specified as an EF1 implementation in E1.20.

The language of E1.11 is quite muddy in this area but having lived through all the fist fights thats were going on back in the late 90's and early 2000's when we were writing this I can say the intent was very clear in the group that we were disallowing 2 universes of DMX512 data on the XLR. We were specifically referring to this with the phrase in Section B1, "However, not all historical uses will be allowed to continue."

-------
Not trying to restart or continue the 5pin vs. 3pin war again, but STEVETERRY said it best here:

Not much has changed on this issue since 1998, when I wrote this article, with some grinding of teeth!
Whose network is it, anyway? Why the end user is the loser in the DMX512 connector controversy

 

[Footer]

One can do that, and there are even commercial products to accommodate this use ( Data Products™ Cables & Adaptors: Universe Saver Adapter Set | Lex Products ), but it is specifically disallowed in ANSI E1.11 - 2008.

Then you have fun things like this....
http://files.avolitesdownload.com/Manuals/Pearl2004/Pearl2004_Man270804.pdf

1.1.2 Connecting DMX lines
The Pearl can output DMX down 4 separate lines. When you patch a
dimmer or fixture you can tell the Pearl which DMX line it is on. The
lines are identified by the letters A,B,C,D. Normally A comes out of
output 1, B comes from 2, C from 3, and D from 4, but just to add to
the fun you can swap this round if you want (see Patching, section 2).
The 4 DMX outputs come out of the 5 pin XLR sockets on the back of
the console. The Pearl 2004 has four separate sockets. The Pearl 2000
has only two sockets with two DMX lines on each, so you will need
splitter cables to access all four lines on the Pearl 2000. They are wired
like this:
Pearl 2004 Pearl 2000 DMX line
Socket Pin numbers Socket Pin numbers
1 (normally A) 1 & 3 2=Data -
3=Data +
1 & 3 2=Data -
3=Data +
2 (normally B) 2 & 4 2=Data -
3=Data +
2 & 4 2=Data -
3=Data +
3 (normally C) 3 2=Data -
3=Data +
1 & 3 4=Data -
5=Data +
4 (normally D) 4 2=Data -
3=Data +
2 & 4 4=Data -
5=Data +

The sockets marked “1 & 3” and “2 & 4” on the Pearl 2004 have pins 4
and 5 connected to the other DMX lines as with the Pearl 2000, making
the Pearl 2004 outputs pin-compatible with the Pearl 2000 if replacing
one console with the other.

I am actually suprised that this never really caught on. It would help to get by the 512 restriction with a bit less cable. I think if the 3 pin thing never happened it very well could have.

 

[gcpsoundlight]

The standards that I have looked at for DMX-512(A) say that pins 4&5 are for a second universe, or remote monitoring (RDM).

 

[Footer]

The standards that I have looked at for DMX-512(A) say that pins 4&5 are for a second universe, or remote monitoring (RDM).

RDM was designed to work over pins 2 and 3, not 4 and 5. This is because many places cable inventory even if it does have all 5 pins, only the first 3 are terminated. Therefore, RDM was designed to piggyback on top of DMX data.

 

[dramatech]

As long as we are muddying the waters of understanding, I will throw one more into the ring. The Strand "Colour Call" scrollers, used five pin XLR connectors with pins 1 thru 3 as normal DMX. Pins 4 & 5 were 24 volts DC.
The concept was a pretty good idea, in that all of your scroller cables could also be used for DMX. The Colour Call scroller was made by Camelont in Sweden, and was pretty much the same as the Rainbow scroller, also made by Camelont. I have several of each, only the Colour calls were changed to 4 pin XLR by the previous owner.

Tom Johnson
Florida's Most Honored Community Theatre