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#2080 06/21/01 09:33 PM
Joined: Nov 2000
Posts: 2,236
Likes: 1
Member
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).]


-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI
#2081 06/21/01 09:38 PM
Joined: Feb 2001
Posts: 308
S
Member
Sounds like Clutch is going for the Guiness record for loudest outdoor concert. Sounds like they're not going to break the record.

#2082 06/21/01 10:24 PM
Joined: Jun 2001
Posts: 161
M
Member
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.


Mike Wescoatt
#2083 06/22/01 05:47 AM
Joined: Oct 2000
Posts: 5,392
S
Member
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]

#2084 06/22/01 08:14 AM
Joined: Dec 2000
Posts: 4,294
Member
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?)

#2085 06/22/01 09:55 AM
Joined: Jun 2001
Posts: 161
M
Member
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...


Mike Wescoatt
#2086 06/23/01 09:20 AM
Joined: Dec 2000
Posts: 84
C
Member
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)

#2087 06/23/01 09:25 PM
Joined: Nov 2000
Posts: 2,236
Likes: 1
Member
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....


-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI
#2088 06/23/01 11:22 PM
Joined: Nov 2000
Posts: 2,236
Likes: 1
Member
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]


-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI
#2089 06/23/01 11:35 PM
A
Anonymous
Unregistered
>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.

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