DMX - RJ45 adapters

[tomo2607]

Morning all,

 

I know similar questions have been asked about DMX over CAT6, but this relates more towards adaptors rather than the use of CAT6...

 

Im looking at buying these as a way of getting DMX from the control desk to the dimmers / DMX splitter. Has anyone used these or anything similar?

 

Some background info...

 

Basically, I work in a large community school. I have finally been given a small amount of funds for improvements in the performance space. As part of this, we are having a control booth constructed at the back of the venue which will house the LX and sound control equipment (dimmers and amps still at stage). Originally we had a 16 way analogue snake that ran from the mix position to the stage, of which 1 way was used for DMX. This is now being replaced with a digital snake at stage end, and a number of CAT6 runs from the new booth to the stage, terminated in a CAT6 Patch panel... Hence my need for DMX over CAT6. Note this is not over ethernet, just the CAT6 infrastructure.

 

Any thoughts or recommendations?

[timsabre]

To avoid extra connectors which can drop out, I would just cut a cat5 patch cable in half and solder XLR's onto it.

Orange-white = DMX+ (xlr pin 3)

Orange=DMX- (xlr pin 2)

Brown/white=DMX ground (xlr pin 1)

 

Those adaptors should work though. But personally I don't like big long things like that stuck out of an XLR as it's easy to damage the XLR if someone bangs it.

[mac.calder]

They work - quite well. I've used a couple with Enttec Storm8 artnet nodes

[Tomo]

I would recommend running Cat5/6 in the wall, and then terminate it into a panelmount XLR-5 connector using an IDC version of an XLR-5.

That way the XLR-5 is in a nice panel (on the wall, in a nice patchbay etc), visitors don't get confused and adapters don't get lost.

 

As long as you leave a couple of inches of slack the Cat6 can be re-terminated to an RJ45 socket in the future if you ever switch to Ethernet instead.

 

ETC use Phoenix 8-pin sockets for both dimmer racks and panelmount XLR-5, these have IDC and screw terminal plugs so you just pick the one you need given the cable you're pulling.

 

- Take caution with the cut-a-patch-lead in half approach, as Cat5/6 patch leads have very skinny cores which are a bit fiddly to solder and easily snapped.

They are however dirt cheap, so they're a reasonable consumable.

[sunray]

I do everything I can to avoid adapters and have surprisingly few, I have always preferred to make the appropriate cable. I have the crimpers to do RJ style plugs but it's tricky finding nice cable to fit, the idea of cutting a patch lead to make a cable is a good one but I suggest buying stranded patch leads for 2 reasons, obviously because they're flexible and should last longer than solid. Secondly I have generally found the insulation is a little less prone to heat damage. Interestingly I have found there seems to be 2 standards for cat5 DMX, green pair for data with brown ground and the version Tim shows.

[musht]

Interestingly I have found there seems to be 2 standards for cat5 DMX, green pair for data with brown ground and the version Tim shows.

 

2nd universe

 

https://www.etcconnect.com/Support/Articles/DMX-Over-Cat5.aspx

[AndyJones]

We use TMB sneak snakes to run data to our trusses:

 

http://www.tmb.com/products/82-sneak-snake

 

E2A

 

I've found not all installs seem to have the chassis wired up. For an install I would only use the two or three universe options as that uses all of the standard pins.

[xllx]

 

- Take caution with the cut-a-patch-lead in half approach, as Cat5/6 patch leads have very skinny cores which are a bit fiddly to solder and easily snapped.

 

 

I have a couple of boxes which I made up, with an ethercon on one side and a 5 pin xlr on the other. Wired using the ESTA standard found on the ETC website. Much more robust than a cable adaptor, and wired internally with solid core Cat 5, which makes it easier to solder into the XLR5 which I happened to have available.

 

Yes you need a patch cord to link the box to the venue infrastructure, but as long as there isn't a switch in the path, this has been a useful "get out of jail" adaptor to have in the toolkit.

 

If you are a venue where adaptors might get lost, you could always fit these adaptor boxes to the wall at either end and just use a normal Cat 5 patch cord to connect them into your infrastructure.

[sunray]

<br />

<br />  Interestingly I have found there seems to be 2 standards for cat5 DMX, green pair for data with brown ground and the version Tim shows.<br />

<br /><br />2nd universe<br /><br /><a href='https://www.etcconnect.com/Support/Articles/DMX-Over-Cat5.aspx' class='bbc_url' title='External link' rel='nofollow external'>https://www.etcconne...-Over-Cat5.aspx</a><br />

<br /><br /><br />

Yes I get second universe, but...

Surely the 'normal' wiring of a universe [ie between fittings etc] is on the orange pair and would only hop onto the second pair when combined into one cable. I try to compare this with a whole universe using pins 4&5 in XLR.

This is not a field I have much experience in so Apologies if I'm talking out of my...

[musht]

<br />

<br /> Interestingly I have found there seems to be 2 standards for cat5 DMX, green pair for data with brown ground and the version Tim shows.<br />

<br /><br />2nd universe<br /><br /><a href='https://www.etcconnect.com/Support/Articles/DMX-Over-Cat5.aspx' class='bbc_url' title='External link' rel='nofollow external'>https://www.etcconne...-Over-Cat5.aspx</a><br />

<br /><br /><br />

Yes I get second universe, but...

Surely the 'normal' wiring of a universe [ie between fittings etc] is on the orange pair and would only hop onto the second pair when combined into one cable. I try to compare this with a whole universe using pins 4&5 in XLR.

This is not a field I have much experience in so Apologies if I'm talking out of my...

 

Your overthinking it ;-) 1 pair and ground on Orange is one universe, Green pair can be used for another entirely separate universe on the same cable.

 

4 way Sneak Snake adaptor goes a bit further by commoning the grounds to get more universes, this is where any potential difference between different ground references could cause issues.

[timsabre]

4 way Sneak Snake adaptor goes a bit further by commoning the grounds to get more universes, this is where any potential difference between different ground references could cause issues.

That's a bit naughty actually. The 4-universe version relies on screened cat5 using the screen as the ground for all 4 universes. However they don't say this anywhere on the website though it is in the data sheet. If used with unscreened cat5 the DMX will be floating and may or may not work.

[sunray]

Your overthinking it ;-) 1 pair and ground on Orange is one universe, Green pair can be used for another entirely separate universe on the same cable.

<br /><br /><br />

I don't think so but it may be the case. My main experience in this field is nightclubs: infrastructure, hanging and addressing units, and a little amdram.

I have installed a number of splitters, description: oval enclosure about the size of 2 pringles tubes side by side, dark grey and dark red shiny plastic [please don't ask make as I have no idea], DMX in and 12v at one end and 6 to 8 DMX out t'other end. First one I did with orange pair [as I was used to] but it only used the green pair. Unfortunatly I had to put the tower back up to crimp new plugs. Also some American LED's fitted with RJ45's. It's a real pain when one has to flip back and forth between orange and green, a dam sight worse than XLR3 & XLR5 as the plugs look the same. Adding another fitting in the middle can suddenly need proper tools and not just a spanner.