New Installation

[chap73]

Hi

I'm working on the renovation of a community/school hall over here NZ. Every supplier wants ot give conflicting information about what I should do so I'm looking for a bit of guidance.

Our stage is 11m wide and 6m deep. I've finally decided that I will put 3 11m long lighting bars in. I'm using galvanised tube not prewired because of the tiny budget. The school only has a roll of 100 students. I plan to site the bars as follows - 1 at 1.5m from back of stage. 1 front of house (about 3m from stage front). 1 behind the procenium - about 2m from front stage.

We're installing an infrastrcture as 3-phase power isn't available to the hall yet so we have to wait 4 months for the power upgrade and dimmer pack installation (12 channel planned). I'll address one question only as this post is getting long!

We're wiring permanent powerpoints at 1m centres along the FOH bar, leading back to the dimmer pack location. As I understand it these circuits (each point) have a standard power plug on the end which plugs into the dimmer pack control/patch panel? I've been told that I should wire two powerpoints into each plug, working from either end (so position 1 and 12 have one plug, 2 and 11 and so on). In the short term we've been loaned some LED fixtures so I also need some powerpoints next to the dimmer to plug the circuits into for LED use.

Question is, is the above the right way to go and what other cabling needs to go to the powerpoints does each point need DMX cabling to it for LED and future dimmer controlled lights?

I've been told I use cat5e cabling for DMX and I should put 1 point to the bar only?

I appeciate any help anyone can give.

Thanks

Paul

 

[Les]

For each pipe, I would wire them as follows:

1,2,3,4,5,6,7,8,9.

-not-

1,2,3,4,5,4,3,2,1.

Redundancy only causes issues, especially if the matching circuits are on opposing ends of the pipe. I can see how it can be an easy way to tie two fixtures for area lighting, but then you are always tied to that configuration. Wire them all separately at this time. If you only have 'x' amount of dimmers installed, you can tie them together at that time if you have to.

I would also wire in circuits for non-dim applications. These circuits shouldn't go to the dimmer rack. You can use these for the LED's. See if you can even get as far as wiring them to a switch in the booth.

As far as the cat5 for DMX goes - yes only 1 output per pipe is adequate since DMX devices can be daisy-chained.

 

[shiben]

If I understand the way they want you to drop circuits, that is silly and i would not do it. Try and have 1 channel per 1 position, this is much nicer. In my college's chapel, they have 2 positions per 1 channel of dimming, and its a pain in the rear. Try and have 1 channel per 1 circuit if you can afford to do that. Also, if you can afford to do it, you might want more than 12 channels of dimming. Do you ever intend to do plays in the space, or is it just an assembly hall of sorts? Its always nice to have more dimmers available than you might need right away, because even a simple lighting set will quickly consume a lot of lights.

 

[mstaylor]

I agree with everybody that one plug to one dimmer if possible. If you have to go to two plugs to one dimmer then start at one end or the other and do the 1,2,3,4,5 then start at center and do it again. That way you can tie both sides of an area together. This is a last resort but if you have to use the doubling method that's the best way.

 

[chap73]

Thank you Les, Shiben and Michael

Just to get it clear in my head. If we have one channel per fitting and have the three bars with say, 12 on the foh, 6 on the stage and 6 on the bos positions I will have 24 cables coming into the AV booth/area (where we're planning to hve the dimmers installed). This would mean 24 cables with 24 plugs and potentially two 12 channel dimmers.

In addition to this we would need some switched powerpoints in the same location so that we can plug some of the plugs into sockets for such things as the LED fixtures.

As the school won't have dimmers to begin with, if they want to be able to run 12 LED fixtures we would need 12 powerpoints to plug half of the plugs into to liven 12 sockets?

Am I right in my intrepetation that the circuit is literally a socket at the lightbar with cabling running to a plug (a hardwired extension lead in effect)?

Thanks for all your help so far

Paul

 

[shiben]

It depends what kind of LEDs you have. You might be able to daisy chain them together and get away with less circuits, check your type and their requirements.

 

[acoppsa]

Hi Paul,
At our school we have a single socket for each circuit. We have about 50 circuits wired in the building even though we only have 24 dimmers. However we have enough three phase sockets to hire in extra dimmers if we need, so don't worry if you have more circuits than dimmers.
In regard to the non-dim circuits, we have around 6 sockets next to our dimmers but 4 should be plenty for your application because you will probably be able to plug several LED fixtures in the same circuit as long as you have "piggy-back" plugs.
Have a look at some of the pictures on this page Services: Installations , they might show you what I mean.
If you need any advice on specific manufacturers etc in our part of the world, feel free to PM me.

 

[chap73]

Thanks to everyone for your help so far.

It's all beginning to make sense; I've spoken to several suppliers over the last few weeks and everybody has recommended that we get a 24 channel lighting board (Theatrelight Nova). This fits our budget but I'm concerned that it will not give us enough channels.

We'll have 24 circuits in total, if we need channels for anything else ie. floor mounted lights is it accepted practice to double up some of the fixtures to single channels - I think a bigger console is going to be out of the budget.

Paul

 

[kiwitechgirl]

Where in New Zealand are you, and who are you talking to in terms of suppliers? I only ask because I'm also in NZ and can probably put you on to a few people who could be very helpful to you, if you haven't already spoken to them! A TheatreLight Nova, while a great little desk, is not going to be much use if you're running LED fixtures, as you'll rapidly run out of channels - you can address them the same to save channels, but it still limits you as they need at least 3 channels each. You can plug more than one light into a dimmer - up to 2400w in total, so you don't necessarily need one dimmer per light. You can also plug more than one LED fixture into a switched socket on the wall - they draw very, very little power so they certainly don't need one socket per fixture.

Don't wire two sockets into each plug, it will only make life difficult - we have over 250 waylines for only 120 dimmers and it just gives us a lot of flexibility. Paired waylines only restrict you.

 

[tcahall]

With regard to your DMX cabling, if you put one drop per pipe, you are setting yourself up to purchase a DMX splitter as DMX is a daisy chain network. Since you are using CAT 5, it is pretty inexpensive to place a CAT 5 drop at each end of the pipe with a home run connection to the dimmer room. In the dimmer room, you can use a CAT 5 patch panel to terminate the cables. This will allow you to patch them together to create a daisy chain across the pipes or take one from each pipe to an opto splitter, should you choose to do so in the future. Finally, looking forward, if you ever go to Ethernet on your fixtures, it is a point to point network which will require a hub on the pipe or more point to point cables. I don't think this is close enough to justify cabling to every position, but I would definitely put one on each end of each pipe.

Tim.

 

[JChenault]

I agree with everybody that one plug to one dimmer if possible. If you have to go to two plugs to one dimmer then start at one end or the other and do the 1,2,3,4,5 then start at center and do it again. That way you can tie both sides of an area together. This is a last resort but if you have to use the doubling method that's the best way.

While I think that most of us will agree that, give lots of dimmers, one circuit ( Powerpoint in the OP parlance) is best - when you don't have enough dommers ( and 24 is probably not enough) you need to have multiple circuits per dimmer.

I would even go further than mstaylor and suggest that you should look at doubling some dimmers between pipes. Running cables from the third electric to the FOH pipe is a drag. Doubling in this way can make life easier down the road.

Note - this is only in the sense of 'I do not have enough dimmers and I need to make do' not 'This is what I want'

The other point I am not seeing discussed here is any kind of wall pocket or floor pocket.

 

[kiwitechgirl]

While I think that most of us will agree that, give lots of dimmers, one circuit ( Powerpoint in the OP parlance) is best - when you don't have enough dommers ( and 24 is probably not enough) you need to have multiple circuits per dimmer.

I would even go further than mstaylor and suggest that you should look at doubling some dimmers between pipes. Running cables from the third electric to the FOH pipe is a drag. Doubling in this way can make life easier down the road.

Note - this is only in the sense of 'I do not have enough dimmers and I need to make do' not 'This is what I want'

The other point I am not seeing discussed here is any kind of wall pocket or floor pocket.

I don't think the OP is talking about having circuits hardwired into the dimmers though - everything I've read indicates that there will be a hard-patch at the dimmer end of things, and so therefore doubling between pipes is redundant - over here in New Zealand we only have one plug system and we're able to piggyback plugs so hard-patching is very easy. More circuits than dimmers in this situation I don't see as a problem - like I said in my earlier post, we have over 250 waylines for 120 dimmers and it means we can pair up as we need to for each different show and design.

 

[cutlunch]

Hi

I'm working on the renovation of a community/school hall over here NZ. Every supplier wants ot give conflicting information about what I should do so I'm looking for a bit of guidance.

Our stage is 11m wide and 6m deep. I've finally decided that I will put 3 11m long lighting bars in. I'm using galvanised tube not prewired because of the tiny budget. The school only has a roll of 100 students. I plan to site the bars as follows - 1 at 1.5m from back of stage. 1 front of house (about 3m from stage front). 1 behind the procenium - about 2m from front stage.

Is the stage flush with the front of the proscenium or does it jut forwards of it?
Without knowing where the proscenium is in relationship to the stage may make my next question invalid.
The lighting bar behind the proscenium should be no more then one metre from it so you can light the stage near to the proscenium.

We're installing an infrastrcture as 3-phase power isn't available to the hall yet so we have to wait 4 months for the power upgrade and dimmer pack installation (12 channel planned). I'll address one question only as this post is getting long!

Have you specified the three phase circuits yet?
You should try to get at least 60 Amps per phase dedicated to the lighting.
However due to cost you may find you land up sharing the load with the general hall / even some classrooms. This can be a real nuisance when it comes to balancing loads.

Do you have an electrician who can do this for you cheaply eg wholesale prices?
Why I ask is you may find that pre-wired bars are the cheaper way to go when labour and cable are considered.
Eg Take for example FOH at 3 metres from the stage then add another 3 metres to get to the dimmer room.

Say 11 non paired sockets at 1 metre intervals on the FOH. Straight off that's 66 metres of cable just from the end of the bar.
Then add 10 + 9 + 8 + 7 + 6 + 5+ 4 +3 + 2 + 1 = 55 ( I've probably forgotten the odd metre) So about 120 metres of cable just for FOH.

Please excuse me if you have done these calculations already.
NB: Especially as I have just seen you are a Quantity Surveyor.

Also do you have enough suspension points to support the FOH bar for heavy moving lights? Some schools don't when they put their bars up. With standard lights it's not such a problem but when you want to use moving lights and it becomes a problem as they can be quite heavy.

We're wiring permanent powerpoints at 1m centres along the FOH bar, leading back to the dimmer pack location. As I understand it these circuits (each point) have a standard power plug on the end which plugs into the dimmer pack control/patch panel? I've been told that I should wire two powerpoints into each plug, working from either end (so position 1 and 12 have one plug, 2 and 11 and so on). In the short term we've been loaned some LED fixtures so I also need some powerpoints next to the dimmer to plug the circuits into for LED use.

Question is, is the above the right way to go and what other cabling needs to go to the powerpoints does each point need DMX cabling to it for LED and future dimmer controlled lights?

I've been told I use cat5e cabling for DMX and I should put 1 point to the bar only?

I appeciate any help anyone can give.

Thanks

Paul

Finally I get to your question.

Having worked in a number of NZ schools where they have doubled up on circuits on the lighting bars I can tell you that single circuits is the only way to go.

Due to lack of dimmers you can always double up the circuits on a dimmer channel but once you double a circuit you can't split it.

On your FOH I would probably put an even number of ciruits such as 12.
Depending on your money I would probably add another circut in the middle of FOH to run things like Video Projectors.

For the DMX I would run a cat 5 to each lighting bar but have it on the bar as a standard 5 pin XLR outlet. But as mentioned you should use a DMX splitter to drive the line to each bar. Also don't run the cat 5 with the power cables. Although it will take more cable run the CAT 5 in from the end furtherest away from where the power comes into the bars. It may save headaches later.

For powerpoints needed to drive things like the LED lights a number of double points with
a 15 amp circuit rated for each double point set will help. A minium of two sets would be a good start. Most things like Moving lights don't take 10 amps per unit. So you should be able to get two to three units per 15 Amp circuit.
As for the lighting boards, as has been pointed out the Nova 24 would not have enough channels to run the LED lights.

I wouldn't normally suggest it but if the LED lights are all you will have for a while then maybe a DJ's lighting board may do for now.

Eg Surplustronics - 192 Channel DMX Controller
I am not saying get this exact board but it gives you an idea of what I am thinking.
This board would only work with the LED lights but there are others wich handle both moving as well as standard lights. But it could get you going while money is saved for a better board.

I am only suggesting this as a stop gap measure if you can't afford a bigger board.
The minimum board I would get is a Nova 36 but this would not be my first choice.

Another option might be a software computer based lighting desk.
Such as the NZ made Light Factory
LightFactory - Products

The software is quite advanced and will handle both moving lights and conventional lights.
If anything it might be to complicated. But for the price break it might be worth it.
For the the software and USB DMX dongle is about $1000NZ
You can pay more and add the capability to add a physical DMX desk etc.

A show I was involved with recently used it with 4 moving lights and 60 channels of conventional. Apparently it played up one night but a quick exit and reload restored it. But was fine otherwise.

But this was being run on a personal laptop not a dedicated computer so there might have been problems there.

I am in Auckland so if you are between Whangarei and Hamilton approx I could come and see you some time to help sort out what the suppliers are saying if you like.

You can PM me if you like.

Brent

 

[chap73]

Hi

Sorry I haven't replied to all the help and questions yet - quite a lot of information to digest and respond to!

I really appreciate everyone's help and will look through the thread tonight and post a reply.

Thanks for everyone's input

Paul

 

[chap73]

Hi Brent

Is the stage flush with the front of the proscenium or does it jut forwards of it?
Without knowing where the proscenium is in relationship to the stage may make my next question invalid.
The lighting bar behind the proscenium should be no more then one metre from it so you can light the stage near to the proscenium.

The stage finishes about 2m infront of the procenium, the FOH bar is about 3m in front of that and the BOS bar is 1.5m away from the back wall so the bars are spaced, roughly, 5m apart from FOH to BOS

Have you specified the three phase circuits yet?
You should try to get at least 60 Amps per phase dedicated to the lighting.
However due to cost you may find you land up sharing the load with the general hall / even some classrooms. This can be a real nuisance when it comes to balancing loads.

Do you have an electrician who can do this for you cheaply eg wholesale prices?
Why I ask is you may find that pre-wired bars are the cheaper way to go when labour and cable are considered.
Eg Take for example FOH at 3 metres from the stage then add another 3 metres to get to the dimmer room.

Say 11 non paired sockets at 1 metre intervals on the FOH. Straight off that's 66 metres of cable just from the end of the bar.
Then add 10 + 9 + 8 + 7 + 6 + 5+ 4 +3 + 2 + 1 = 55 ( I've probably forgotten the odd metre) So about 120 metres of cable just for FOH.

Please excuse me if you have done these calculations already.
NB: Especially as I have just seen you are a Quantity Surveyor.

I think our electrician said we can get 50a per phase but we won't know for sure until we get the new transformer installed in several months. The hall is just outside the school grounds as it is a rural school so it has its own power supply.

Also do you have enough suspension points to support the FOH bar for heavy moving lights? Some schools don't when they put their bars up. With standard lights it's not such a problem but when you want to use moving lights and it becomes a problem as they can be quite heavy.

I'll have to look at this one, at the moment we've got one suspension point at each end and then at 1800mm centres - this lines up so we have suspension points on roof truss positions. I think this will be okay unless anyone can tell me different.

Having worked in a number of NZ schools where they have doubled up on circuits on the lighting bars I can tell you that single circuits is the only way to go.

Due to lack of dimmers you can always double up the circuits on a dimmer channel but once you double a circuit you can't split it.

On your FOH I would probably put an even number of ciruits such as 12.
Depending on your money I would probably add another circut in the middle of FOH to run things like Video Projectors.

For the DMX I would run a cat 5 to each lighting bar but have it on the bar as a standard 5 pin XLR outlet. But as mentioned you should use a DMX splitter to drive the line to each bar. Also don't run the cat 5 with the power cables. Although it will take more cable run the CAT 5 in from the end furtherest away from where the power comes into the bars. It may save headaches later.

I had planned to put the CAT5 socket in the ceiling at the end of the bar (would CAT6 or CAT5e be better?). I had planned a standard socket - is the 5 Pin XLR the way to go?

For powerpoints needed to drive things like the LED lights a number of double points with a 15 amp circuit rated for each double point set will help. A minium of two sets would be a good start. Most things like Moving lights don't take 10 amps per unit. So you should be able to get two to three units per 15 Amp circuit.
As for the lighting boards, as has been pointed out the Nova 24 would not have enough channels to run the LED lights.

The latest plan was for four single, unswitched, 10 amp sockets. Would this be sufficient over here in NZ?

I think we will probably use the NOVA 36, but the software option looks really interesting. I'll look into that.


Thanks for all of the help.

Paul

 

[tjrobb]

I won't comment on power needs as I only work in the US, but I can comment on the Cat5.

For Ethernet you shouldn't run LESS than Cat6 - Cat5 is obsolete (except for voice) and 5e not much better (IMO). If you are only running DMX you may be able to use 5e, but if plan to use an Ethernet-based DMX in the future I would run 6 for the lines. At the least you don't have to pull better lines in the future.

 

[chap73]

I won't comment on power needs as I only work in the US, but I can comment on the Cat5.

For Ethernet you shouldn't run LESS than Cat6 - Cat5 is obsolete (except for voice) and 5e not much better (IMO). If you are only running DMX you may be able to use 5e, but if plan to use an Ethernet-based DMX in the future I would run 6 for the lines. At the least you don't have to pull better lines in the future.

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

 

[cutlunch]

Hi Brent


The stage finishes about 2m infront of the procenium, the FOH bar is about 3m in front of that and the BOS bar is 1.5m away from the back wall so the bars are spaced, roughly, 5m apart from FOH to BOS

Thanks for the measurements it gives me a better picture.
But I would still make the bar just inside proscenium no more then 1 metre from the proscenium so you can light the stage close to the proscenium without having too much of a dark spot. This is somewhat dependant on the height of the proscenium arch and the height of the FOH bar. If the FOH bar is to high then light from there will only fall on the front of stage leaving a band under the proscenium. To low and the light from there will go to far upstage. The ideal angle from the bar to the stage is 45 degrees theorectically but it's not always possible.

I think our electrician said we can get 50a per phase but we won't know for sure until we get the new transformer installed in several months. The hall is just outside the school grounds as it is a rural school so it has its own power supply.

The latest plan was for four single, unswitched, 10 amp sockets. Would this be sufficient over here in NZ?

You won't be able to change the 50a per phase without the transformer costing quite a bit more. If you get all the 50 amps then it should be enough. The only problem is when the start taking some to light and heat the hall.

The four single 10 amp sockets should be alright if they are each on their own seprate 10 amp fused circuit or two on a 20 Amp fused circuit.

At home total up the amperage as 10 amps per each switched socket you have. Then look at the ratings of the circuit breakers / fuse holders assigned to power points in your switchboard. You will probaly find that the actual available power from the switchboard is lower then the total of all the power plugs at 10 amps.

The same can be done in offices / schools etc. The basis for this is that it unlikely every socket will be fully loaded.

I'll have to look at this one, at the moment we've got one suspension point at each end and then at 1800mm centres - this lines up so we have suspension points on roof truss positions. I think this will be okay unless anyone can tell me different.

That spacing will be fine, there is a lot more suspension points then I thought there would be.
The only thing is how much weight each suspension point can handle.
I would work on having each 1.8 metre section being able to bear a weight of 50Kg's + pipe weight preferably 100Kgs + pipe weight then you would never have problem.
But as a quantity surveyor you'll know more about load bearing then I will.

I had planned to put the CAT5 socket in the ceiling at the end of the bar (would CAT6 or CAT5e be better?). I had planned a standard socket - is the 5 Pin XLR the way to go?

Unless you plan to have a lot money to buy fancy lighting desks then CAT 6 wouldn't be needed. Cat 5 is more then high spec enough for the DMX signal.

Here's a link about DMX512 and Cat 5 showing the standard way to wire Cat 5 for DMX512.
DMX512 FAQ - USITT

Your dimmer packs and Nova desk should use 5 Pin XLR connectors so I would try and stick to that as the main connectors. This is also because proper DMX512 cable is more flexible which is what you need when you run DMX512 to individual units. The Cat 5 is designed for fixed wiring. So you can use it to run to the bars ok.

Although depending on the quality of the LED lighting you are being loaned you might find they only use a 3 Pin XLR so you might need to make an adaptor. But as you daisy chain the DMX units you would only need an adaptor at the start of each daisy chain. Remembering that if you have a DMX units on each bar it might pay to get a DMX splitter and run one output to each bar. They normaly have one input 4 outputs typically.

If you are only going to have LED lights for the next few years and they only have 3 Pin XLR you could wire for them. But it would probably be best to use 5 Pin.

Hope this helps.
Brent

 

[kiwitechgirl]

The latest plan was for four single, unswitched, 10 amp sockets. Would this be sufficient over here in NZ?

Provided you can get 10A per socket without overloading the ring main, absolutely. We've got four single switched sockets in our dimmer room for hard power, and currently they're running six Mac250s, three Mac600s, about ten LED bars, a baby compressor for a hazer and a 2kW smoke machine without any problems.

I think we will probably use the NOVA 36, but the software option looks really interesting. I'll look into that.

IMHO, don't bother. While it is a great piece of software, in a school situation you really do want "handles" so that a teacher who knows nothing about lighting can switch the desk on and bring up lights by pushing a fader. A software solution, while giving you a lot of power for your dollars, is much more complicated for someone with no knowledge to operate - there's a very good reason why you'll find a TL desk in the majority of schools around the country! The Nova is a solid, easy-to-use yet surprisingly powerful little desk.

 

[tjrobb]

To elaborate on previous posts, you can run 5e for just DMX, but if you plan on running Ethernet I would recommend 6 (eDMX should be fine over 5e as well, it doesn't require the speed capabilities of 6). In most cases though, 5e will be fine for DMX.