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Posted By: sparky66wv "Best Boy" work... - 06/22/01 01:33 AM
OK, I've bitten off more than I can chew...

A farm owner has decided to have a music festival. The headlining band is a group called "Clutch" Go here for tour dates, check out 8-4-01...

Anyway, it is up to moi to change a cow pasture into a amphitheater / sound stage, electrically, that is.

The list of requirements from Clutch is:
Power:
200 Amp 3 phase for sound
300 Amp 3 phase for lights

No mention of voltage or any other info.

Just what kind of sound equipment runs on 3 phase?

The nearest 3 phase supply is at least ten miles away...

Why so much amperage? The WV State Fair only uses two 200A for Pete's sake!

If they insist on seperate services for the lights and the sound (due to hum), will I have to put in an ISO Xformer? Or just put in two discos mounted to the same meterbase and convince them it's OK?

The production manager for the festival says that Clutch is only bringing instruments and such, "we" are to provide the sound gear and lighting (there must've been a mouse in his pocket).

I told him I need nameplate ratings on every piece of equipment that will be present at the gig, all the way down to individual coffee pots, outdoor lighting, etc. I need nameplate ratings on the lighting gear and the sound equipment, etc. etc. none of which has been even bid for yet...let alone decided on.

Any and all help will be greatly appreciated.

Oh yeah, somehow the production manager thought I said $7.00 per hour... I laughed in his face! I said no less than $20, and I'll include all time involved, office, travel and meetings. So far I've got about 4 hours involved...

[This message has been edited by sparky66wv (edited 06-21-2001).]
Posted By: Steve T Re: "Best Boy" work... - 06/22/01 01:38 AM
Sounds like Clutch is going for the Guiness record for loudest outdoor concert. Sounds like they're not going to break the record.
Posted By: Mike Wescoatt Re: "Best Boy" work... - 06/22/01 02:24 AM
If they really need all that power (sound guys usually don't, lighting does for most things) rent a pair of diesel generators and a pair of distros (look to your "local" theatrical rental house) to supply them with 120/208 3 phase wye power. Sound could live on a 10-12kW and lights will need about 30-35kW. I'd ask them again what they ---need--- and not what they ---want---. See if they will bring their own distro and use your "local" theatrical rental house... they've undoubtedly done this many, many times.

Hope this helps... Check back with more questions.

p.s. I ran 4/0 feeders 3PH/5W from a 400A disco to a distro 200' away for sound amps and they pulled a whopping 26A peak per phase... They really didn't need the 400A service, and I really didn't need to lug around all of that copper.
Posted By: sparky Re: "Best Boy" work... - 06/22/01 09:47 AM
I've never seen a 3 ph sound board. is'nt the common request to put the instruments AND sound all on the same phase to cut down on tyhe mic's arcing singers?

Don't most light guys use the low-V models, less heat to cook players? I mean 300A ! who has 100,000 watts of light on stage? what a barb-Q!!!
I like Mike's suggestion....

[Linked Image]
Posted By: electure Re: "Best Boy" work... - 06/22/01 12:14 PM
West Virginia-stock. Cool. The gennies sound like the way to go. All the sound/lighting people I've worked with have had a tendency to massively overestimate their power needs. Your plan to get a list of their equipment is a good one.
(Are you playing there as well?)
Posted By: Mike Wescoatt Re: "Best Boy" work... - 06/22/01 01:55 PM
Agreed the sound board isn't 3PH but any sound systems I've worked on of any size have been 3PH. The one installed in our building right now is three phase on three different transformers on three different 12.4kV feeds to help eliminate buzz. As long as the sound guys are on their own grounding system (they'd prefer no ground) buzzing isn't a problem unless their equipment is broken (including broken signal conductors) or hooked up wrong.

Yes, these people do usually overestimate their loads... I think rock band U2 had over 1GW of protable power for their last tour...
Posted By: cinkerf Re: "Best Boy" work... - 06/23/01 01:20 PM
Sparky,

The Amphitheater our Pittsburgh Symphony uses (and many well known visiting groups) is powered by a 120/208V. 3 Ph. 4W. 200 Amp service. There are also several air conditioned dressing rooms and small conference rooms. We never had any difficulties.

Frank (cinkerf)
Posted By: sparky66wv Re: "Best Boy" work... - 06/24/01 01:25 AM
The latest news:

Clutch is only bringing 120V amps, etc. all 15A or 20A plugs.

The promotion director for the festival will rent lights and sound from local outfits, all will be either 120V or 240V, uh, "single phase" (ahem)...

As long as I'm certain that no breakers will trip, I can put in anything I want.

I say a single 200A 120/240V service will suffice, but I'm still waiting for nameplate data...

Should I use all GFCI and risk a "nuissance trip" (and blow my guarantee and my reputation) or call some recepts "dedicated" to prevent it?...

I've been told not to mix surge protectors and GFCI's do to shunting of spikes tripping the GFCI. Any more suggestions?

There will be more questions....
Posted By: sparky66wv Re: "Best Boy" work... - 06/24/01 03:22 AM
Another Update:

Here's an Email I received from the sound people...
Quote

The ELECTRICAL
requirements for sound are as follows: #1 at the front of house
mixing tent, one 20 amp circuit,{ I could get by with 15 amps there if
you're short of amps elsewhere} #2 at the main stage I need two circuits
,one 30 amp for front of house system and one 20 amp circuit for the on
stage monitor system. IMPORTANT !!!! ALL THREE CIRCUITS SHOULD DRAW FROM
THE SAME BUSS BAR as well as the circuits for instruments on stage and be
PROPERLY PHASED so as to avoid ground loops . ALL LIGHTING AND CONCESSION
POWER SHOULD DRAW FROM THE OTHER BUSS SO AS TO AVOID SYSTEM NOISE FROM THE
LIGHTING DIMMERS AND VOLTAGE DROPS FROM OVENS,REFRIGERATION ETC. FOLLOWING
THESE RECOMMENDATIONS SHOULD INSURE A CLEAN SOUND FREE FROM VOLTAGE SPIKES
OR DROPS DUE TO LOAD CHANGES FROM THOSE OTHER SOURCES. I look forward
to working together to produce a successful show. KARA SWEETWATER

Wow... I'm not used to such straight forward, intelligent answers like this...

Great idea on splitting the loads by Buss too... How come you guys didn't think of that? (You probably did, but assumed I knew it too being as I'm the big musician / electrician and all?) [Linked Image]
Posted By: Anonymous Re: "Best Boy" work... - 06/24/01 03:35 AM
>Should I use all GFCI and risk a "nuisance trip"
I would if they said that their equipment didn't cause nuisance tripping.

But if you can't test in advance and they won't waive you on it, then there is a real risk that they have dirty equipment.

>I've been told not to mix surge protectors and GFCI's on account of shunting of spikes tripping the GFCI.
That is true with some brands.
Posted By: sparky66wv Re: "Best Boy" work... - 06/24/01 03:36 AM
I like it except for the 30A part...

A 30A 120V recept? Or Am I supposed to split the busses on a 240V circuit?!?!?!

I've asked them for ALL voltages, I am only assuming 120V on the 15A's and 20A's.

I'll find out soon enough...Maybe...

[This message has been edited by sparky66wv (edited 06-23-2001).]
Posted By: Anonymous Re: "Best Boy" work... - 06/24/01 03:48 AM
>at the main stage I need two circuits, one 30 amp for front of house system and one 20 amp circuit for the on stage monitor system.
Make sure your outlets have the right prongs.

>and be PROPERLY PHASED so as to avoid ground loops.
If she says so. Does she mean properly wired?

>POWER SHOULD DRAW FROM THE OTHER BUSS SO AS TO AVOID SYSTEM NOISE
You can't avoid it all.

What she really needs is an SDS so that there is a separate transformer to eat the noise.

Can they afford a surge suppressor right in the panel? Put it on a dedicated 20 A double pole breaker. Get one of those expensive ones that tightly tracks the waveform. You can't be too careful in a cow pasture.
Posted By: Anonymous Re: "Best Boy" work... - 06/24/01 03:52 AM
>A 30A 120V recept?
There is such a beast.
[Linked Image from quail.com]

>Or Am I supposed to split the busses on a 240V circuit?!?!?!
I would say not. But I don't know what you mean either.


[This message has been edited by Dspark (edited 06-23-2001).]
Posted By: sparky66wv Re: "Best Boy" work... - 06/24/01 04:38 AM
I do realize that 120V 30A recepts exsist... (RV's) I was merely asking if it was likely that it was what she meant.. Of course, she is the only one to know.

It would be a special order item here...guaranteed.

I was being sarcastic on splitting the busses... there's no way to split up two 240V circuits so that they don't share a buss....DUH! (Not meant to insult)
Posted By: sparky Re: "Best Boy" work... - 06/24/01 11:07 AM
66'
A customer with a detailed request ! I'm jealous!
So, are you going to construct a 200A temp service? Will it be a one time fee rental?

will you allow us to get all coded out on you?

Will this be an art 305 and/or 525 venture?
I like you 'dedicated' idea via 525-18(b),and could (c) be taken to mean your there , toolbelt on, fluke in hand?
[Linked Image]
Posted By: electure Re: "Best Boy" work... - 06/24/01 02:15 PM
Virgil,
IMHO, I should think you'd want to use Twistlock recps wherever you can. Not only will they give you a little more assurance of continuity of service, but the L5-30R (120/30) recp might be easier to get. But, then, there's the ? of $.
Posted By: sparky66wv Re: "Best Boy" work... - 06/24/01 02:24 PM
Yeah!

Oh definitely "Code Me"... If anything goes wrong I want to be covered...

And yes, I will be there, toolbelt on and fluke in hand... (A requirement of Clutch is an on-site sparky, besides, I wouldn't miss it. Clutch is a very good band, if you're into their style...like AC/DC meets Zappa with some angst thrown in...)

The 200A service and other parts not yet defined will be permanent. The "farmer" wants to do this every year with other bands if it is successful.
Posted By: sparky Re: "Best Boy" work... - 06/24/01 05:00 PM
hmmmm;
Another Yazgood!
I would imagine permanent service would be a better sale, as there are probably some high $$$ needs that would 'rent' fairly $$$.

anyway, i suppose you now need to separate permanent from temp. Is the service close enough to all served ( or heaviest loads) to simply have a receptacle bank ?

if your present does 410-57(b)(2) apply? Gotta job every gig they do?
Posted By: sparky66wv Re: "Best Boy" work... - 06/25/01 02:39 AM
The Twistlocks are a great idea, I was already considering them...

The inuse covers are also expensive, and may not be necessary as per 410-57(B)(2) like you suggest.

Is SO cable the likely temp cable I can use?
It's very plentiful here... What with the mines and all...

What's the best way to guard the cables? Walkways (beer will be present...) will be hard to control, it's a big concern right now...I'd rather trench and bury everything, but you know how that i$.

I think I'll get to talk them in to trenching out to at least a few areas that will require more than a single 15A 120/240V circuit.

How much of a voltage drop can I accept?
The voltage is on the high side in most places here, usually 122 or 123V per leg.
Plays heck on cheap light bulbs... But gives a little headroom in voltage drop. Can I go as little as 115V? Or even 110V?

Many more questions will follow... Probably more and more with a hint of panic too!
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