New Installation

If you plan for forward-compatibility, Cat6 is what you should use.
 
If you plan for forward-compatibility, Cat6 is what you should use.

I agree with the Cat6. Why limit the capabilities for a few pennies. It's true for DMX you don't need it but Cat5 is at the end of it's usefulness, so why put something in that could be obsolete in a few years.
 
Thanks, from the ends of the lighting bars should the CAT6/5e run to the dimmer packs (which are near the stage) or the lighting desk at the back of the hall?

Am I going to cause the school problems placing the dimmer packs (when they eventually get the power required) in a cupboard by the stage. It had thought that they were going to go in a cupboard (which is not very big) with grilles with filters in the doors and an extractor fan to run when they are being used.

Paul
 
It depends on where you will put your DMX splitter eventually. The Cat5/6 will not need to run through the dimmer, but you may find that location to be a good place to distribute the DMX signal from. Just make sure that it is easily accessible should you need to repatch the lines. It would probably be cheaper to just run one line (or 2 or however many DMX universes you will use) to backstage and then distribute from there.
 
It depends on where you will put your DMX splitter eventually. The Cat5/6 will not need to run through the dimmer, but you may find that location to be a good place to distribute the DMX signal from. Just make sure that it is easily accessible should you need to repatch the lines. It would probably be cheaper to just run one line (or 2 or however many DMX universes you will use) to backstage and then distribute from there.

Sorry, I'm still not sure of where the splitter comes in? If I've got a cat6 from each end of the lighting bars (making a total of 6 runs) going into the dimmer cupboard will that not take care of it - I think I've completely misunderstood the use of the DMX/cat6 cable? Originally I had been told that I just needed to run one DMX cable from the end of each lighting bar back to the lighting desk - have I been given bad advice by the lighting supplier?

Sorry if I appear stupid, I've digested a lot of info in a short space of time and some of it's not 'clicking'!

Paul
 
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What your looking at needing is something called an opto-isolated splitter, and the use of this is to properly split the signal and distribute it out to each output. this device will keep the signal from having issues on the various devices.
 
I'm sorry, I should have explained better. The DMX signal will come from the lighting board to the stage. Generally, there will be one continuous line from the board to the first fixture to the second fixture to the third fixture and so on until you get to the last fixture. You can either go down one lighting bar then cable from that to the next bar or you can split the signal so that you can run one cable to each bar rather than wiring everything together. If you are not going to be using the DMX right off, you don't really need to worry about this yet. However, what I am assuming that the supplier is thinking is that there will eventually be a splitter at the same location as the dimmers. This will take the line coming from the desk and send the signal to the six lighting bars.

I could be misunderstanding you, and if I am, I apologize, and I hope that someone else will confirm this for you or say that I am completely wrong....
 
It might be clearer with a quick DMX lesson. You will be running what is known as an one universe system, this means you will have 512 DMX channels. You need to either daisy chain all the lights or you have to split the lines. This can only be done with an opto splitter, any other way creates DMX bounce or echos that will make your lights do wierd things. What your supplier was probably thinking was you were only running conventionals so you only needed a line from the board to the dimmer.
Since you will be using LEDs you will signal for them. What I would do, and it's been suggested already, is run the cable from the board to your dimmer location, then put an opto splitter at the dimmer location and plug your Cat6 into them.
Hopefully this helps you understand our advice. Remember that you will have to daisy chain the LEDs on each catwalk. The conventionals will get their signal from the dimmers.
 
A couple of things to consider, and perhaps someone from ETC may want to comment further.

Basically there are two different situations here, one is using CatX cable to run an ethernet based lighting protocol that is then either supported directly by the device or converted to standard dmx

The other case is running actual DMX over CatX cable.

If you are using the former, ie an Ethernet derivative, then I would go with Cat6 cable for future use. Make sure you remember the cable limits, there is a 300 foot limit on the direct run (which is typically solid core) and a 30 foot limit in the final patch cable (which is typically made from stranded)

If you are running true DMX over Cat 6 then I would think that you might need to look at a shielding conduit for a more problem free install or using the shielded version of the cable. Typically the shield in the cable is only connected at one end for ethernet . I know the twisting is supposed to off set the problems of not shielding, but IMO it is not as robust a solution, and if you start having problems after the install you are going to go crazy. As I mentioned there are STP cable versions that might make more sense. DMX in its native format is NOT a very fast protocol and so the benefits of Cat6 might not be there especially over some of the shielded cables. On the other hand if you are running an Ethernet based system then the added speed might be of value in the future.

In the future I think more and more systems are going to go the direction of Ethernet based, BUT today, the most reliable problem free cabling system for native DMX is proper dmx cable.

Sharyn
 
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So I need to put CAT6 in with a 5 pin XLR point - this can then be used for the DMX control of the lights and will 'future-proof' the installation - have I understood that correctly?

Paul

The CAT 5 vs CAT 6 argument gets very technical, and very esoteric, very quickly. If you are planning on running gigabit Ethernet to the bars, then CAT 6 is a good idea. If you think 100 Mb/s will transport your lighting control signals for the foreseeable future, CAT 5 or CAT 5e is fine.

WIth regard to termination, I would put an 8 pin RJ-45 jack on a faceplate on the bars (at each end). Then have a batch of RJ-45 to XLR-3 and XLR-5 (male and female) adapters made to plug in at each end of the bar (male at one end, female at the other). This future proofs your installation, allows easy installation of current technology and allows an upgrade to Ethernet by ditching the adapters.

Tim.
 
The CAT 5 vs CAT 6 argument gets very technical, and very esoteric, very quickly. If you are planning on running gigabit Ethernet to the bars, then CAT 6 is a good idea. If you think 100 Mb/s will transport your lighting control signals for the foreseeable future, CAT 5 or CAT 5e is fine.

WIth regard to termination, I would put an 8 pin RJ-45 jack on a faceplate on the bars (at each end). Then have a batch of RJ-45 to XLR-3 and XLR-5 (male and female) adapters made to plug in at each end of the bar (male at one end, female at the other). This future proofs your installation, allows easy installation of current technology and allows an upgrade to Ethernet by ditching the adapters.

Tim.

Make sure you use the etherCON for your RJ-45 jacks. This way, your adapters will lock in using a more robust format then the plastic clip. This will save you hassle of taping your adapters to the pipe, and will work longer term.

Neutrik - Data Connectors - etherCON Cable Connector Carriers - NE8MC

Note, this will not keep you from using a standard ethernet cable either, so if you needed to plug in a stand alone CAT6, or use the EtherCON cables.
 
Make sure you use the etherCON for your RJ-45 jacks. This way, your adapters will lock in using a more robust format then the plastic clip. This will save you hassle of taping your adapters to the pipe, and will work longer term.

Neutrik - Data Connectors - etherCON Cable Connector Carriers - NE8MC

Note, this will not keep you from using a standard ethernet cable either, so if you needed to plug in a stand alone CAT6, or use the EtherCON cables.

That answers what was going to be my next question which was - I assume something like this would be a good choice!

Audio Video Wholesalers

Thanks for all the help I'm getting. I wish I had found this site 3 months ago - the information and help I'm finding here exceeds that given by suppliers!

Paul
 
That answers what was going to be my next question which was - I assume something like this would be a good choice!

Audio Video Wholesalers

Thanks for all the help I'm getting. I wish I had found this site 3 months ago - the information and help I'm finding here exceeds that given by suppliers!

Paul
I don't mean to offend anyone but some suppliers shouldn't be. I have dealt with some that I had to teach them how their equipment worked. This is an exception, there some great guys out there but some could just well be selling shoes.
 
I don't mean to offend anyone but some suppliers shouldn't be. I have dealt with some that I had to teach them how their equipment worked. This is an exception, there some great guys out there but some could just well be selling shoes.

I didn't mean to offend anyone either - I'm sure most suppliers are really helpful and like mstaylor said this is an exception . I guess getting advice from end users makes it easier to ensure you get the right set-up.

Paul
 
I would definitely recommend getting as many dimmers as you have the money/power to support. Also, run circuits individually from the lighting positions/bars/floor pockets to a central patch panel, where you can plug them into any dimmer you want. this way, you're not locked into any specific doubling arrangement, and can change your circuits around depending on what you need.

As far as control goes, make sure you get something that has enough channels to support your dimmers. If you plan on using movers, I would strongly recommend having wheels or encoders of some type (not just normal faders) for ease of use, especially in a school setting.

I would recommend an ETC board, but that's just what I have experience with, so it's rather biased.

For dimmer location: someplace where they have adequate ventilation, and don't cause noise on stage. relatively easy access would be a good idea, in case anything goes wrong or you need to change any settings.
 
Hi Paul

Unless you are likely to be given a really big budget for the lighting in the next couple of years I wouldn't use ethernet connectors.

If you use ethernet sockets at the end of each DMX line you will have to buy adaptors.
You will be better off just using 5 Pin XLR sockets. Every time you have an adaptor it is something else to loose. And from experience in schools they will get lost.

The cupboard idea for dimmers might not work based on a standard cupboard design.

As well as the space you need for the dimmers you need to allow room for the 3 phase power. You should have at least 3 switched 3 phase outlets. Don't put the 3 phase outlets to close in a vertcal line or too close to horizontal shelf sticking out past them. This because some dimmer packs have right angle plugs as opposed to straight ones.

Plus the single phase power outlets.

Also you need space for the patch panel. Your one will need probably at least 33 plugs based on your lighting bar design. There are multiple designs for patch panels.
There are some prefabricated ones you can buy or custom build your own.

So instead of a cupboard I would make it more like an alcove, wider then it is deeper. Then put metal grill doors on it to allow for better ventilation.

I'll be interested to see what you do for final design.

Brent
 
Hi Paul

Unless you are likely to be given a really big budget for the lighting in the next couple of years I wouldn't use ethernet connectors.

If you use ethernet sockets at the end of each DMX line you will have to buy adaptors.
You will be better off just using 5 Pin XLR sockets. Every time you have an adaptor it is something else to loose. And from experience in schools they will get lost.

The cupboard idea for dimmers might not work based on a standard cupboard design.

As well as the space you need for the dimmers you need to allow room for the 3 phase power. You should have at least 3 switched 3 phase outlets. Don't put the 3 phase outlets to close in a vertcal line or too close to horizontal shelf sticking out past them. This because some dimmer packs have right angle plugs as opposed to straight ones.

Plus the single phase power outlets.

Also you need space for the patch panel. Your one will need probably at least 33 plugs based on your lighting bar design. There are multiple designs for patch panels.
There are some prefabricated ones you can buy or custom build your own.

So instead of a cupboard I would make it more like an alcove, wider then it is deeper. Then put metal grill doors on it to allow for better ventilation.

I'll be interested to see what you do for final design.

Brent

The way the space has worked out has left me with a space to the side of the stage which I'd planned to use for the dimmers. I was looking at putting some doors with large grilles on them (possibly filters). The inside of the cupboard measures (approx) 1.6m wide, 0.76m deep and 2.8m tall. I would put an extractor in to give some airflow too.

Paul
 
Might I suggest a real rack instead of a makeshift one? In the grand scheme of things, a real metal rack designed for this purpose may work better and look more professional in the long run. Especially if you're going to have three phase in it, I would feel more comfortable having it all run in a professional and real case.
 
Might I suggest a real rack instead of a makeshift one? In the grand scheme of things, a real metal rack designed for this purpose may work better and look more professional in the long run. Especially if you're going to have three phase in it, I would feel more comfortable having it all run in a professional and real case.

Not sure if I've been misunderstood but the space I was talking about for the dimmers is actually part of the building not a makeshift rack. I think the architect who has redesigned the space originally saw it as a storage cupboard but we're looking at utilising it for the dimmers. The dimmers we've been looking at are wall mount theatrelight comets.

Paul
 
The dimmers we've been looking at are wall mount theatrelight comets.

Why? They are nice little packs, but they have some bells and whistles which aren't going to be much use to you. Also, you only get six channels per 32amp 3-phase - yes, you can load them more heavily, but more channels at a lower rating is much more use to you as it gives you far more flexibility. The Theatrelight PowerPack would be a much better option; 12 10-amp channels per 32amp 3-phase; they're units which have been around for donkey's years and are still going strong. They don't need a rack built for them, as they stack on top of each other; the sockets are on the front, not the back (the Comet's are on the back so you'd have to mount them sideways to be able to get at the back and front of them) and they're incredibly robust with very little to go wrong - the Comet has much more electronic gubbins to have problems with! I would really advise against the Comet as it's just not a unit that is 100% suited to your needs. The PowerPacks may be a little more expensive (I don't have access to a TL price list so I'm not sure) but honestly, it is well worth it. My local hire company has one Comet pack, and it spends 99% of its time on the shelf, only going out when all the other packs are out on hire, or we need a 10amp single-phase dimmer.
 

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