# Electricity Question: Dimmer Feeds



## Shawncfer (Jul 11, 2010)

Hm.. Okay, so electricity question for yall...

So I have a Sensor 48/96 rack. And I know you can buy a D50AF module, meaning you can have up to 50 amps in one module correct?

Okay, so If theres 48 modules in a rack then thats 2400 amps for the whole rack...correct?

And if its three phase then each phase should have 800 amps... correct?

So it'd be a 3phase disconect with 800amps? Is that right?


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## Sony (Jul 11, 2010)

No, not neccessarily, rarely if ever is the supply of a dimmer rack rated for every single module in the rack to be on at full at the same time. Much more commonly a Sensor 48 rack will be powered by a 400amp or 600amp feed as it is cheaper and much more economical to install and rarely will a rack be loaded to even close to 50% capacity at one time. That being said a Sensor 48 rack IS rated to have up to an 800amp feed installed so it could be possible. The only way to tell for sure what your dimmer rack is being fed with is to find the circuit breaker feeding the rack itself and read the rating on that circuit breaker. Even the rating on the disconnect is misleading, as often the disconnects are rated for higher than the circuit breaker feeding it since they often come in stock sizes or were what the contractor had in stock with a high enough rating.


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## Shawncfer (Jul 11, 2010)

Okay so another question. If i have regular D20s, but lets say im only using a S4 750w on that dimmer. Then it would only be putting out 6.25 amps right? So even if every dimmer was on but every dimmer was plugged into a S4 750.. then that would be 200 amps per phase right?


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## derekleffew (Jul 11, 2010)

Shawncfer said:


> ... Then it would only be putting out 6.25 amps right? So even if every dimmer was on but every dimmer was plugged into a S4 750 ...


Some adjustments in thinking may be beneficial. Rather than a dimmer "putting out," the load (lamp) draws current, up to the dimmer's circuit breaker's rating. Likewise, a dimmer isn't plugged into a S4 750, but the opposite.

See also the collaborative article Dimmer Feeds-How Power Much Is Enough?


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## dcollins (Jul 11, 2010)

derekleffew said:


> Some adjustments in thinking may be beneficial. Rather than a dimmer "putting out," the load (lamp) draws current, up to the dimmer's circuit breaker's rating. Likewise, a dimmer isn't plugged into a S4 750, but the opposite.


 
However his mathematics is correct. 96 channels*750W=72kW, 72kW/120V=600A and assuming correct load distributions, 200A per phase. However there's more to add, depending on why you're asking:

If you're talking about an existing installation, you should plan to load each phase no more than 80% the rating of the breakers (and of course the rating of any intermediate devices, such as cables and your dimmer rack). This is required for constant loads per NEC, and is good practice otherwise. In addition, it is wise to base all calculations on the total number of instruments that will be in the air, and you should not take into account things like the lights not all being on at the same time during a show - LDs and directors change their minds too often, and uneven loading makes it impossible to do that anyway.

If you're planning a new installation, then again your rated supply current should be no less than 125% of the maximum expected load - and you should be relying on someone other than the internet to design such things


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## icewolf08 (Jul 11, 2010)

Shawncfer said:


> Hm.. Okay, so electricity question for yall...
> 
> So I have a Sensor 48/96 rack. And I know you can buy a D50AF module, meaning you can have up to 50 amps in one module correct?


 
Here is a side note on the use of 50A modules (D50AF). While a D50AF will fit in any open slot in a Sensor rack, the backplane of the rack has to be wired correctly for the output. A D50AF module is NOT a dual module, it has only one dimmer instead of two like the D20. Thus you can't just pop one in when you need it, you have to have the proper wiring out of your rack and in your walls or raceways.

It is possible to convert a slot in your rack to or from a 50A slot, but this should only be done by an ETC certified technician and the output wiring would need to be done by a licensed electrician.


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## Shawncfer (Jul 11, 2010)

Okay so lets pretend that I had two S4 750s twofered into each dimmer. The two lamps together would draw 1500w right? So 1500*96 = 144kW 144kW/120v=1200 amps...

So is that possible? Would the disconnect be rated for 1200 amps? or 400 (per phase)? And if it is per disconnect as a whole, then is it possible to see a 1200 amp disconnect?

And hypothetically according dcollins, if I have ONE S4 750 on each dimmer, and its 200 amps per phase, then I should plan to have 250 amps on each phase just to be safe right??? And ontop of that I have to have the correct size cable right? And the Nuetral has to be rated for 200% of each hot? In other words so the nuetral can handle 2 times the ammount of amps that the hots are rated for correct? Is there anyway of knowing what size awg you need per ammount of amps?

And if I have an installed rack already and it has 200 amps per phase, then I should only have enough lights so that it doens't exceed 160 amps correct?


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## SteveB (Jul 11, 2010)

Your thought process is generally correct, BUT...

1) Purchasing and installing a Sensor 48 module rack and populating it full of dual D20 dimmer modules for a total of 96 dimmers @2400 watts each, then providing a service of 200 amps per phase (600 total amps), is a waste of the money spent on the install. The labor to install is a huge portion of the overall cost of the system, and you need to think ahead and not limit yourself to a 750 watt load limit per dimmer (if every dimmer were used). 

2) The reason the rack is rated to 800 amps, is to allow for the main breaker to be rated at 800 amps, as required. Main breakers are de-rated 20% if used with incandescent loads at continual loading over 3 hrs. (I believe is the figure). Thus if you provide a 400 amp main then de-rate by 20%, you end up with 320 amps per phase/960 total, for a dimmer limit of 1200 watts, or half the rating of the dimmer. Again, not particually cost effective. If you install an 800 amp main, then de-rate 20%, you get 640 amps, which allows every dimmer to be loaded to near max. Note that ETC Sensor dimmers have no de-rating as the circuit breakers allow for full loading for continuous use. 

3) I have no idea if every Sensor rack installed gets an 800 amp main breaker, I would guess that 600 might be more common, with touring racks having a 400. 600 is often a good compromise as it allows for close to capacity of the rack.

4) It's also not a good assumption that dimmers don't get loaded full and that not every dimmer gets used. Movies and TV studios are typical exceptions to what is common in theater, which is lighter loading with smaller loads from fixtures. As a rental hall, I did not assume that my space would bever get used for a movie or TV shoot and fought for a 600 amp service per rack, when the electctical engineer wanted to give me 400. Granted my rep. plot doesn't use 600, but I cannot limit some future event. 

5) You can legally power a rack with a 15 amp 3 pole breaker, if that's what your demand load is going to be, but why waste all that capacity ?.

SB


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## Sony (Jul 11, 2010)

Shawncfer said:


> Okay so lets pretend that I had two S4 750s twofered into each dimmer. The two lamps together would draw 1500w right? So 1500*96 = 144kW 144kW/120v=1200 amps...
> 
> So is that possible? Would the disconnect be rated for 1200 amps? or 400 (per phase)? And if it is per disconnect as a whole, then is it possible to see a 1200 amp disconnect?
> 
> ...



Yes the total load would be 1200 amps or 400 amps PER PHASE. The disconnect would be rated as per phase, so if you have a 400amp three phase disconnect it could support 1200 amps total but the rating is for each individual phase. This is because each phase inside the disconnect can only support a maximum of 400 amps and any more would damage the switching components for that particular phase. 

Yea you are correct, you should always have 125% of the capacity you are expecting to need as overhead, more if possible. The neutral needs to be rated at 133% of a single phase in a three phase system. So if you have a 400 amp three phase system then you are required to have a neutral that can handle 532amps (i.e. 133% of 400 amps) this is because in an ideal world with completely balanced loads there is actually 0 current returning on the neutral because the phases cancel each other out. However if you were to have 100% load on the first phase, 50% load on the second phase and 0% load on the third phase you could theoretically have a 133% load on the neutral conductor because they do not cancel each other out.

Figuring out the AWG size needed is as simple as searching for an AWG Chart on the internet. In fact I do believe there is one on CB in the Wiki under AWG.

As for your last question...No, it is unlikely that you will use all of your fixtures at full so going over the rated capacity is fine as long as you don't expect to turn them all on at once. Also you have 200 amps PER PHASE so 600 amps total, so your total load by your calculations should never exceed 480 amps across all three phases combined. However, like I said, almost NEVER in a design will you have 100% of your design at full, in fact more often than not it will be more like 50% of your design will be utilized at one time.

For example, when I designed Dracula for Island Moving Company in Newport, RI, I had a 100amp 120/240vAC single phase feed or 200 amps total. I hung 75 Source 4's at 575 watts a piece. That is 75 * 575 = 43125 watts or 43125 / 120 = 359 amps. So I hung almost double what the feed was rated for total. I did this however knowing that I would never use more then 40% of the plot at a time because the show was promenade so it was spread across multiple rooms and only one room was used at a time and that I properly balanced all my loads across both phases so it was never very far out of balance.


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## STEVETERRY (Jul 11, 2010)

SteveB said:


> Your thought process is generally correct, BUT...
> 
> 1) Purchasing and installing a Sensor 48 module rack and populating it full of dual D20 dimmer modules for a total of 96 dimmers @2400 watts each, then providing a service of 200 amps per phase (600 total amps), is a waste of the money spent on the install. The labor to install is a huge portion of the overall cost of the system, and you need to think ahead and not limit yourself to a 750 watt load limit per dimmer (if every dimmer were used).
> 
> ...


 
Preface: I've known you for almost 40 years, and we've installed a lot of systems together.

BUT, with all due respect, you're wrong.

Take a look at the attached ETC Load Survey. It's far less power per rack than you suggest.

It's not just the cost of the power service, it's the associated cost of the HVAC capacity.

Cheers

ST


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## Shawncfer (Jul 11, 2010)

SteveB said:


> 2) The reason the rack is rated to 800 amps, is to allow for the main breaker to be rated at 800 amps, as required. Main breakers are de-rated 20% if used with incandescent loads at continual loading over 3 hrs. (I believe is the figure). Thus if you provide a 400 amp main then de-rate by 20%, you end up with 320 amps per phase/960 total, for a dimmer limit of 1200 watts, or half the rating of the dimmer. Again, not particually cost effective. If you install an 800 amp main, then de-rate 20%, you get 640 amps, which allows every dimmer to be loaded to near max. Note that ETC Sensor dimmers have no de-rating as the circuit breakers allow for full loading for continuous use.


 
Yeah you totally lost me with that...

And something random and off topic Im wondering about... Does single phase have two hots and a nuetral or one hot?


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## DuckJordan (Jul 11, 2010)

Soxred93 said:


> One hot and a neutral.


 
and depending on the device, A ground. (although do not confuse ground with neutral as they are not the same thing)


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## dcollins (Jul 12, 2010)

Shawncfer said:


> Okay so lets pretend that I had two S4 750s twofered into each dimmer. The two lamps together would draw 1500w right? So 1500*96 = 144kW 144kW/120v=1200 amps...
> 
> So is that possible? Would the disconnect be rated for 1200 amps? or 400 (per phase)? And if it is per disconnect as a whole, then is it possible to see a 1200 amp disconnect?


You'll usually see them rated per phase, so 400A disconnect. You already know about not loading the disconnect to more than 80%, though.


> And hypothetically according dcollins, if I have ONE S4 750 on each dimmer, and its 200 amps per phase, then I should plan to have 250 amps on each phase just to be safe right???


Yep


> And ontop of that I have to have the correct size cable right?


Yep


> And the Nuetral has to be rated for 200% of each hot? In other words so the nuetral can handle 2 times the ammount of amps that the hots are rated for correct?


I'm not sure on the exact rule. 200% sounds like a good number, but consult an electrician for the actual rules and common practices.


> Is there anyway of knowing what size awg you need per ammount of amps?


The NEC (national electrical code) is the standard for electrical in the USA, and you can find that information there. There are also a million web pages with tables for this information. As always, only an electrician can ensure that you are using the right size and type of cable, and that the cable is undamaged and safe to use.


> And if I have an installed rack already and it has 200 amps per phase, then I should only have enough lights so that it doens't exceed 160 amps correct?


That's probably a good number - per phase. But then you need to know how your phases are set up. For my rack, dimmers 1 and 2 are on phase A, 3 and 4 on B, 5 and 6 on C, 7 and 8 on A, etc., however this is not the only way it is done. Electrically, it's also best to ensure that your phases are as balanced as possible (if all three phases are equal, there will be very little current on the neutral wire, this is a good thing) however for the most part no one actually worries about that unless they have serious power issues.


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## derekleffew (Jul 12, 2010)

Shawncfer said:


> ...Does single phase have two hots and a neutral or one hot [and a neutral]?


Depends on whether it is 110 or 220V.

The three most common services encountered by a stage electrician (in North America) are:
1. Single Phase, 120V: hot + neutral
2. Single Phase, 220V: hot + neutral + hot. Hot to hot =240V, Hot to neutral = 120V. (Also called split-phase).
3. 3Ø, 120/208VAC, Wye Connected: hot, hot, hot, neutral. Hot to hot =208V, hot to neutral = 120V.

When dealing with dimmer packs/racks, voltages above 120V aren't germane, as a single dimmer is never connected across phases. The output is always a maximum of 120V. (Intentionally ignoring supply voltage, line losses, and losses through the dimmer.)


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## JChenault (Jul 12, 2010)

STEVETERRY said:


> Take a look at the attached ETC Load Survey. It's far less power power per rack than you suggest.
> 
> ST



Steve

Very interesting data. Are the raw numbers available?

I would be interested in knowing ( for example) the various load factors for various venue types, or looking at load factors based on number of dimmers in a venue.


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## STEVETERRY (Jul 12, 2010)

JChenault said:


> Steve
> 
> Very interesting data. Are the raw numbers available?
> 
> I would be interested in knowing ( for example) the various load factors for various venue types, or looking at load factors based on number of dimmers in a venue.


 
We have the raw data, but I have not looked at it since 2005. I will try to find what you ask for.

ST


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## derekleffew (Jul 12, 2010)

JChenault said:


> ... I would be interested in knowing ( for example) the various load factors for various venue types, or looking at load factors based on number of dimmers in a venue.


I'm not sure the raw data would tell you very much of value. For instance, if I remember correctly, I submitted data for both an installed DPC system (lots of empty dimmers) and a corporate one-off in a ballroom (where one seldom rents more dimmers than required).


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## STEVETERRY (Jul 12, 2010)

It should be possible to extrapolate some data from the "no load" category of the survey.

ST


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## SteveB (Jul 12, 2010)

STEVETERRY said:


> Preface: I've known you for almost 40 years, and we've installed a lot of systems together.
> 
> BUT, with all due respect, you're wrong.
> 
> ...


 
As a preface. When ST tell me I'm wrong, it certainly makes me re-think my comments, so as reply

Steve, 

I'm assuming you take exception to my recommendation to supply a 96x2.4kw dimmer rack with a 600 amp service, correct ?. And that your disagreement is based on the load survey of 2005 that clearly indicates that the typical loading is nowhere near 20 amps per dimmer, in a typical theatrical space. One thing that is not clear in the survey is that with TV and Film facilities being roughly 8 percent of the survey (but not necessarily 8 percent of all the systems in existence, just what responded) what are their loading requirements ?. And do other facilities ever have the need to load dimmers at or near there capacity of 20 amps ?. The survey Food for Thought summary even indicates the troublesome question of “How many 2.4kw dimmers” would be appropriate and that's an un-answered question.

So perhaps a follow up survey would answer whether the managers of the lighting systems would feel comfortable with a system made up exclusively of 1.2kw dimmers. I don't even begin to know how to establish that for my own space,, although I would probably be just fine with it, and with a number of deck located 2400 watt dimmers available. 

But where does that leave the end user ?. The survey was done in 2005 and answered what everybody suspected about how the Source 4 575 watt lamp, as well as other follow on similar lamps, has greatly reduced the need for fairly large feeder systems. The Food for Thought comments correctly asks if 1200 watt dimmers should become the norm, and the answer is Yes.

But 5 years later, and unless I'm not seeing something on assorted company websites, no manufacturer of installed rack dimming systems makes a 1200 watt dimmer in a modular design, which is the most useful configuration, unless you consider assorted systems that are 12/24 dimmers mounted in a 19” rack type design, but whose individual dimmers are not modular, per say. I'm assuming that the reason is that the existing 2400 watt systems are so cost effective to manufacturer, that the companies are awaiting a drop in component costs before they move to the next generation of sine-wave at 1200 watts, in a modular design that is as effective as the current industry standard Sensor, as well as similar Strand systems.

So if I think like a consultant (which I am not), or an end-user that has to think about this often and I ask myself, can I simply just install a 96x2400 rack and pretend it's a 1200 watt dimmer (cause that's what's available) and then provide a feed that is roughly half what was recommended 10 years ago ?. Hardly. I would not do that and I think it's bad practice to recommend that. Yes, the loading is reduced and in truth, the industry is changing very quickly with a requirement for dedicated power for LED's as well as 208/240 volt power for ML's, but until the dimmer size itself is reduced, I would hesitate to assume that the loading is not ever going to increase to use up some of that 20 amp dimmer capacity. 

Recall as well that you wrote an article many years ago about the concerns in under-feeding a dimmer rack, as it can reduce the usefulness of the capacity of the dimmers and that a desirable method to avoid such “zone limitations” is to buss racks together on a large feed breaker, that allows the capacity of the rack to be used as needed in a zone of the facility, or for the feed capacity to be shared for the smaller loading that is now common. When only one rack is present, bussing is not an issue, but under-feeding may well be. Just for curiosity, do you now think that your recommendations of many years ago are not as relevant today ?. 

EDIT: Some things I forgot:

1) Is it legal/code compliant (in NYC as example) to provide for wiring appropriate to 1200 watt dimmers - I.E. #14 THHN type ?. Or is the NEC and other codes requiring a minimum of 20 amp rating, as that certainly impacts any cost savings in moving to 1200 watt dimmers.

2) If #1 were allowed, what I'd love to see, and that I have a current need in a new building, would be 192 or so, 1.2kw modular dimmers, don't have to be sine-wave, in thw space of a Sensor 48. Like the old LMI quad 1.2's. 

And have we really known each other 30 some odd years ?. How can that be when I'm still 30 ? (grin).

Thanks,


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## derekleffew (Jul 12, 2010)

SteveB , STEVETERRY tells me I'm wrong all the time. It's something one becomes accustomed to--an acquired taste, if you will. 

I wanted to point out that both of Mr. Terry's articles are available for download in the wiki entry Dimmer feeds--How much power is enough? - ControlBooth . 
Note that Mr. Terry provided additional comments on the _Dimmer Feeds_ article:

STEVETERRY said:


> derekleffew said:
> 
> 
> > Summer 2002, in the ESTA quarterly, _Protocol_. See attached. Any revisions you would make today, Mr. Terry?
> ...



SteveB , What size breaker would you use to feed that hypothetical rack of 192x 1.2kw dimmers? 800A, 600A, 400A? Better hope no one ever wants to use striplights or 2K Fresnels.


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## STEVETERRY (Jul 12, 2010)

OK, many things to respond to:

1. There is not much cost difference between a 2400W phase-control dimmer and a 1200W phase-control dimmer--and there never will be. That is why you have not seen 1200W dimmers appear in any significant quantity. Also, imagine a system of 1.2kW dimmers where just a few 2.4kW dimmers were needed. How and where do you deploy them in a way that makes sense? Sure, a 1200W sine wave dimmer costs a lot less than a 2400W sine wave dimmer--so power reduction makes sense in a sine wave environment. But, as we have seen, demand for sine wave dimmers in North America has been minimal. "Sine wave is the party that the dimmer manufacturers gave where nobody came".

2. I am still in favor of power de-rating at the highest possible level to assure the maximum current to any given dimmer rack. This avoids "cables from the balcony rail to the cyc".

3. It is clear that the smaller the system, the less opportunity for feeder de-rating. A single rack system might need less de-rating, but even 600A to a single rack is hard to justify when presented with the results of the load survey.

4. I still like the idea of saving money by rack-to-rack bussing rather than full-sized breakered feeds to each rack.

5. #14 AWG is allowed for 15A circuits.

6. NYC Code is now the same as NEC, except for a few amendments.

7. New sources for the future will draw less current. It's hard to justify excessive feeder sizes when you consider the additional cost of HVAC capacity.

8. Yes, we have known each other for more than 30 years. It means we're both just old farts. 

ST


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## STEVETERRY (Jul 12, 2010)

derekleffew said:


> SteveB , STEVETERRY tells me I'm wrong all the time. It's something one becomes accustomed to--an acquired taste, if you will.


 
Truth be told, you're also right a lot of the time. 

ST


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## SteveB (Jul 12, 2010)

Shawncfer said:


> Yeah you totally lost me with that...



It's all about breaker de-rating. Circuit breakers that power incandescent lighting loads and that operate for more then 3 hours, need to be de-rated, so that you never see a load that is more then 80% of the capacity of the breaker. Now not all facilities are going to operate their incandescant lighting system for 3 consecutive hours, with all the circuits parked at 100%. But some times they do or come close, with TV and Film facilities being a typical example. And sometimes you get an odd European designer that wants a lot of white light and you sit in rehearsal all night in the same ****ed cue, and well you get the idea...

If you have a Sensor 48 module dimmer rack, with 96 dimmers @ 2400 watts per dimmer (and are in a US/Canadian facility with 120 volt line voltage), then you have a connected load of - 96x2400=230,400 watts, divided by the line voltage of 120 = 1920 total amps required to power every dimmer on at the same time. Since these systems are typically supplied with 3 phase power feeds, the amperage draw per phase is 640 amps (1/3 of the amperage total). That's what you need to keep the rack powered with every dimmer loaded full. When you account for de-rating of 20% you need to size up the main breaker accordingly, which is 800 amps per phase, which is why the buss bars in the back of the Sensor rack are rated at 800 amps and why the rack is rated at 800 amps per phase. 

When you choose to not power the rack with an 800 amp, 3 pole breaker, a common occurance, you then start to deal with the potential for every dimmer not being able to be loaded to full, if you assume you use every dimmer. I would venture to say that the smaller the system, say 1 or 2 racks, the more likely that every dimmer gets used, where as with larger systems, say 4 racks or more, that many of the dimmers are occasional use only, though this a is huge assumption and is certainly not true in all instances, but mostly an observaton that facilities with multiple rack numbers often have a lot of spares located around the facility that are occasional useage only.

So lets say you install a 400 amp main breaker for a 96x2.4kw rack. De-rating the breaker 20% yeilds 320 amps per phase/960 total and if you then use every dimmer, you can only load a typical dimmer to 1200 watts/10 amps average. Which might just be fine if your entire inventory consists of 96 S4's @ 750 watts and you only load one fixture per dimmer.

The minute you start adding fixtures beyond 96, or you start using strip lights @2250 watts per circuit, you need now to start being aware of the main breaker limitation, which is something you don't have to pay as much attention to when the breaker rating is closer to the rack rating.


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## derekleffew (Jul 14, 2010)

Here is a real-world example of how important knowledge of the loading and phasing of a dimmer rack can be.

Attached is a map of the power layout:View attachment CorpShowPower2Map.pdf

Two hours before doors, in the midst of programming and client walk-throughs, we noticed the 100' 4/0 feeder getting warm.
Hot, actually, as in too hot to comfortably hold, along its entire length, but hotter nearer each end.
*The black leg measured 405 amps, red was ~350, and blue was ~250.*
Turns out the Production Electrician didn't know how the dimmer rack was phased.
Moving a multi, (12 lamps) from the black phase to the blue brought us into tolerable range, as the numbers on the map reflect.

Even though the dimmer rack was only powering 66 575W lamps, the distribution of those lamps across the phases became critical given that the same service was also powering 60+ moving lights. This was a party, and the conventional lights were being used to light decor, so one had to expect that all the lamps would be at Full the entire evening. As it turns out, the LD decided to run them at about 80%, which was a help.


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## xander (Jul 14, 2010)

This thread turned into a very interesting conversation. Thanks to Steve B, Steve T, and Derek L for sharing their wealth of knowledge with us, shall we say, less worldly folks. 

-Tim


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## Footer (Jul 14, 2010)

Going back to the OP here and the DF50AF modules. I can only assume the DF50 module was made as a retrofit option for venues that have a large number of 6k dimmers and was never intended for use in a new install. I would also have to assume that they were not intended to FILL a 96 rack.


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## sk8rsdad (Jul 14, 2010)

We have a relatively new install and have a single D50AF in the rack for our the overhead house lights (12x500W). I expect other venues may use D50AF's for similar loads.


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## starksk (Jul 14, 2010)

Footer said:


> Going back to the OP here and the DF50AF modules. I can only assume the DF50 module was made as a retrofit option for venues that have a large number of 6k dimmers and was never intended for use in a new install. I would also have to assume that they were not intended to FILL a 96 rack.


 
D50AF Modules are used in new installations every day. They can be used to fill an SR48/SR48+ rack. The catch being that they are single density (one dimmer per slot, not two), need to be installed by a certified technician if the rack wasn't preconfigured at the factory, and require the load wire to be sized appropriately. An install rack full of D50AF modules, while not overly common, has been installed in several venues.

And, yes, you can have a rack full of D100AF modules too. Those modules are 1/2 density (take up two slots for 1 dimmer) and also require special configuration of the rack as well as appropriately sized load wire(s).


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## derekleffew (Jul 14, 2010)

Footer and sk8rsdad , it's D50 or D50AF. A DF50 is a hazer.

@ *starksk*, has ETC ever built a TR24 or TR48 with D50 modules? Did it have Socapex outputs and patching, or just 2P&G-60A direct outs? How about an SP6 with D100s?


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## Sony (Jul 14, 2010)

Footer said:


> Going back to the OP here and the DF50AF modules. I can only assume the DF50 module was made as a retrofit option for venues that have a large number of 6k dimmers and was never intended for use in a new install. I would also have to assume that they were not intended to FILL a 96 rack.



I know of several brand new installations that have D50AF modules, one of them is Newton North High School where I work, which was just completed this month, another I know of is Trinty Repertory Company. At NNHS the D50 modules are used exclusively for house lights, however at TRC we use the D50 modules to power 15" 5k Arri Tungsten Fresnels that are used in almost every production we do there. 


derekleffew said:


> Footer and sk8rsdad , it's D50 or D50AF. A DF50 is a hazer.
> 
> @ *starksk*, has ETC ever built a TR24 or TR48 with D50 modules? Did it have Socapex outputs and patching, or just 2P&G-60A direct outs? How about an SP6 with D100s?


 
I don't know about D100's but I know Trinity Repertory Company has a SP6 full of D50's which we use for powering the 5k Arri Fresnels in the smaller of the two theatre's. The upstairs theatre has dedicated D50's in the 4 SR48 racks, but the smaller theatre uses 3 TR48 racks and a SP6 for it's dimming needs.


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## starksk (Jul 14, 2010)

derekleffew said:


> @ *starksk*, has ETC ever built a TR24 or TR48 with D50 modules? Did it have Socapex outputs and patching, or just 2P&G-60A direct outs? How about an SP6 with D100s?


 
Yes. There have been several different configurations of touring racks built. The standard output method is the 2P&G-60A for 50A modules but there are other custom options available.

As for the SP6 with D100AF modules, it is a standard item with 2P&G connectors. (It is also available as a standard item for the SP12 size pack, and both sizes also have a standard part number for being fully populated with D50AF modules)


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