Cat 5 as DMX ?

[Tomo]

After all, there is no mention of GROUND on the Cat5 wiring layout diagram provided by Tomo...

Brown and Brown/White are the 'common' or 'ground' or 'shield' connections for the primary and secondary link.

Some reciever designs need the common to be there for proper biasing.

 

I've started recommending Cat5 STP/FTP for all DMX installation wiring.

- The shield isn't actually required, but it's considerably tougher then UTP as a numpty has to break through the shield before they can damage the conductors.

 

The big advantage of pulling Cat5 or Cat6 for DMX is it means that they have a lot of 'in-the-wall' network cable for later upgrades.

- There are a lot of uses for that cable!

 

If they decide to change over to an Ethernet system, the wire's already there and they just need to swap the connectors, or it can be used for various other kinds of tieline.

[HobitLight]

Hi guys. Sorry to bring up an old topic but could I use Cat5 for temporary DMX runs? I was thinking I could I take a couple of adaptable boxes and put a panel mount Ethercon connector on each, with two male panel mount XLRs on one box and two female panel mount XLRs on the other, with the boxes wired as per the diagram earlier in the thread. Could this be feasible/ would it work and be reliable?

 

Thanks in advanced,

Hobitlight

[Andrew C]

It'll work electrically. CAT 5 install cable however, is solid core and will eventually break somewhere as you coil it.

 

ISTR that the spec says something like "not to be used between fixtures", which technically, you aren't doing, but the inference is that it is OK to use as fixed, permanent wiring.

[DrV]

It'll work electrically. CAT 5 install cable however, is solid core and will eventually break somewhere as you coil it.

 

ISTR that the spec says something like "not to be used between fixtures", which technically, you aren't doing, but the inference is that it is OK to use as fixed, permanent wiring.

Cat5 patch cable is stranded so will last longer although it's more expensive. eg This from Farnell

 

Dave

[Ashley R]

This is actually one thing that has confused me. Is it ok to use Cat5 cable as temporary cabling (of course using the flexible, stranded version)?

 

I know it is perfectly fine for doing permanent installs, but I would like to start changing over from regular Mic cable (with 3P XLR's) to Something more suitable that has the correct impedance (although still in breach of the standard by using 3P XLR's).

 

And would it be better if I used Shielded Cat5 cable than unshielded? and How much benefit would I get?

[musht]

Cat5 patch cable isn`t particularly tough, PVC sheath is meant for an easy life in a server rack.

[c.cam108]

You can get tougher Cat5:

 

http://www.cld-dist.co.uk/shop/cable/digital/CADURACAT.html

 

I'm not signed in so can't see the price ATM

 

EDIT: Over a pound a metre, so not cheap!

[jexjexjex]

Hi All

 

In amongst this topic, can someone give me a quick "conversion" from the diagram on the previous page, which shows the various core colours, to a 5 pin XLR

 

Thanks

[Tomo]

5-Pin XLR Pinout:

1: Common (Both commons)

2: Data 1 -

3: Data 1 +

4: Data 2 -

5: Data 2+

 

In many installs Data 2 is not connected as it is very rarely used.

[Ashley R]

So its fine to use Stranded cat 5 for temporary work? If so looks like a trip down to the local Electrical Wholesaler to see what they have in stock, as in shielded Cat 5, or one with a tougher sheathing.

[david.elsbury]

Ashley, yes if you want to, the cable does meet DMX spec, but the question is, why would you *want* to, it's still not going to be as robust as proper DMX cable.