Power Distribution

superdoo

Member
So I have recently realized that I know nothing about power distro and it's place in the world. I understand some racks need three phase and what three phase is. But I don't know why some racks have built in distros, some don't, what a pass through really does (I hope it's as simple as I think):neutral: amongs other things that I think we can collectively share.

...Oh yeah let us also touch on various recepticals and plugs.
 
So I have recently realized that I know nothing about power distro and it's place in the world. I understand some racks need three phase and what three phase is. But I don't know why some racks have built in distros, some don't, what a pass through really does (I hope it's as simple as I think):neutral: amongs other things that I think we can collectively share.

...Oh yeah let us also touch on various recepticals and plugs.


Two things....

First of all, it's "distribution".

Second, your question is rather vague. I think asking some more specific questions may lead to a better discussion.


--Sean
 
Commonly lighting world uses power distros for moving lights. Plugging 200 moving lights into the wall is definatly not possible. So the power distros job is to distribute it across plugs. The common power distros for lighting have either soco, locking connectors (commonly L6-20's), or edison plugs, or an assortment of the above. You tie in the power distro using cam (3 phase is much more efficent than single phase), but you cannot evenly distribute single phase across a 3 phase distro (some you can, they have a big switch that generates a third leg, or does some other type of switching). Also power distos in audio world distribute the power amongst the amps, processors, and provide stage power for the band. There are a lot of amps that run at 220 rather than 120 and being able to just plug a big cable into a rack is a lot easier than running mulitple cables.
The pass through is just that, it simply passes the power through the distro, so you can tie multiple distros together. Commonly i plug our dimmer rack into the cam tails, then plug the moving light distro into the pass through on the dimmer rack. It makes the setup a lot more pretty, you do not have T's laying everywhere, and it saves on cam jumpers. It also makes the fire marshall a lot more happy, because then you do not have to worry about recolor coding t's and such.
 
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So I have recently realized that I know nothing about power distro and it's place in the world. I understand some racks need three phase and what three phase is. But I don't know why some racks have built in distros, some don't, what a pass through really does (I hope it's as simple as I think):neutral: amongs other things that I think we can collectively share.

...Oh yeah let us also touch on various recepticals and plugs.

(Note this is simplified and general)

Power distribution, at the most basic level is how we get power from the street into a venue and out to any device that needs power. In general in the US most performance venues are fed with at least 1 (if not many) high amperage three phase lines.

Why three phase? as has been said, it is a much more efficient means to get a lot of power into a building. If you have a 400A three phase disconnect you can connect a 400A load to each phase for a total of 1200A @ 120V (on a USA 3 phase Y system, most common in theatre/performance venues). This system also allows you to utilize "split-phase" or 208V gear like many moving lights as you get 208V from hot to hot.

Now for distros. Essentially a dimmer rack is a type of power distro. Each rack is fed with a high amperage line which is then distributed via the dimmers to lower amperage lines and on out to gear. As with any distribution system every output (or dimmer) in the rack is individually overcurrent protected by either a circuit breaker or a fuse.

What most people think of as a power distro has previously been described in this thread. Generally a distro consists of a box or a panel that takes a high amperage input and distributes that to lower amperage outputs. Every output has to have overcurrent protection so usually on a distro you will see a breaker panel. As has been said, distros can be set up to ouput to many types of connectors. If you were working with a lot of 208V moving lights you would want a distro that has a lot of 208V outputs. If you needed to plug in a bunch of sound amplifiers you may need a distro with more 120V outputs.

As I said in the beginning though, all power distribution and power distros do is give us a way to take the high amperage inputs and split them up for use by low amperage devices.
 
I run Front of House at a local church in Plano called the Spirit of Prophecy Church, and every once in a while we get this unexplained little buzz over the speakers, but when I turn up the headphone monitor and listen on the in-ears I hear no buzz, just a clean, nice mix. I'm not blaming the 16x4x1 Mackie yet, although one morning I jokingly did so to the Praise & Worship leader by taking the board in both hands, looking up and saying, "Found the buzz!" So it's a power issue which is no surprise, because we've got everything plugged into house power and it's a tiny little church, so we need a distro. So how much are we looking at spending? We don't have anything yet in the way in an effects & EQ rack, although it's best to plan for the future. We're not doing anything fancy with lights, and I'm sure the video projector's got it's own circuit.
 
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I run Front of House at a local church in Plano called the Spirit of Prophecy Church, and every once in a while we get this unexplained little buzz over the speakers, but when I turn up the headphone monitor and listen on the in-ears I hear no buzz, just a clean, nice mix. I'm not blaming the 16x4x1 Mackie yet, although one morning I jokingly did so to the Praise & Worship leader by taking the board in both hands, looking up and saying, "Found the buzz!" So it's a power issue which is no surprise, because we've got everything plugged into house power and it's a tiny little church, so we need a distro. So how much are we looking at spending? We don't have anything yet in the way in an effects & EQ rack, although it's best to plan for the future. We're not doing anything fancy with lights, and I'm sure the video projector's got it's own circuit.

Our school has recently had a Powerwise PD1215-3RC installed. See this POWERWISE - Power Distribution Units
 
Our school has recently had a Powerwise PD1215-3RC installed. See this POWERWISE - Power Distribution Units

Urck, what a clunky way to do your RCD protection...
Clearly the manufacturers have been driven by the dollar NOT by a TRUE understanding on the goals of ENTERTAINMENT power distribution...
That and it's ugly

I also fail to see why you would by choice install such a unit permanently... In almost every case it would be more sesnible to have increased mains wired to the relevant part of thae space with a new supplementary DB if that's what was needed.

To the OP, please explain why it is that you have conclusively concluded you have a power issue? What is your current distribution arrangment?
 
Urck, what a clunky way to do your RCD protection...
Clearly the manufacturers have been driven by the dollar NOT by a TRUE understanding on the goals of ENTERTAINMENT power distribution...
That and it's ugly

I also fail to see why you would by choice install such a unit permanently... In almost every case it would be more sesnible to have increased mains wired to the relevant part of thae space with a new supplementary DB if that's what was needed.

To the OP, please explain why it is that you have conclusively concluded you have a power issue? What is your current distribution arrangment?

It is being installed into a pre-existing scholl gymnasium.
 
I run Front of House at a local church in Plano called the Spirit of Prophecy Church, and every once in a while we get this unexplained little buzz over the speakers, but when I turn up the headphone monitor and listen on the in-ears I hear no buzz, just a clean, nice mix. I'm not blaming the 16x4x1 Mackie yet, although one morning I jokingly did so to the Praise & Worship leader by taking the board in both hands, looking up and saying, "Found the buzz!" So it's a power issue which is no surprise, because we've got everything plugged into house power and it's a tiny little church, so we need a distro. So how much are we looking at spending? We don't have anything yet in the way in an effects & EQ rack, although it's best to plan for the future. We're not doing anything fancy with lights, and I'm sure the video projector's got it's own circuit.
How did you determine that it is a power issue and that "a distro" would solve it?

I'll also throw out the usual warning that in public assembly spaces such as churches, school gymnasiums, auditoria and theatres there are elements of installed power distribution system design and installation that should, and often legally have to, be addressed by properly qualified and licensed professionals. It's great to have a good understanding of these systems but they are not DIY systems. Portable and temporary distribution that connects to those installed systems is a different matter and is where the term "distro" is probably most often involved.
 
To serve what loads?

Oh and that would be a school gymnasium...

8x3W LED PAR64's
4x120W Moving Head LED's

This is all as far as I know, so not with sound. The specifications were sketched up by an AV consultant, and they were checked/priced with a AV Suppler/Installer company.

And sorry mate, I made a small mistake yes. Also I am sorry if you find my post on the Powerwise devices stupid, but I am a beginner compared to professionals, and I would appreciate some understanding and acceptance that I do not know every facet of power distribution.
 
8x3W LED PAR64's
4x120W Moving Head LED's

This is all as far as I know, so not with sound. The specifications were sketched up by an AV consultant, and they were checked/priced with a AV Suppler/Installer company.

And sorry mate, I made a small mistake yes. Also I am sorry if you find my post on the Powerwise devices stupid, but I am a beginner compared to professionals, and I would appreciate some understanding and acceptance that I do not know every facet of power distribution.

I'm sorry that you've taken it personally. My beef is with the company who sold it to you or indeed actually the whole raft of people who sell what they can make the quickest buck on as opposed to the the best solution for the application at hand...

Quite honestly, for your loads I'd have had 2 or 3 20A circuits wired off the nearest DB and thrown 2 or 3 DGPOs on each at the relevant location near your patch tails. The incoming plug and socket alone on that distro are around 200 bucks worth...

But never underestimate the value of proper speeling and grammar in the way persons you have never met will get their first impressions of you...
You also need to be aware that in this case, the distro you have referred to will never be suitable for the situation under discussion because he's in the US running 115V and one of the multitude of plug and socket types they use over there, probably Edison...
 

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