I need to run a power for 18000 watt DJ equipment

[ultramegabob]

I got a call to look at running a circuit for some DJ equipment, he told me he needs a 100 amp single phase 4 wire circuit, and described to me what sounds like he plans on using a 50 amp range recept and cord to connect to his system. I told him that there was no way that I would connect it that way, and explained why, he acted like he understood what I was explaining, but said he travels all over the country D.J.ing and never had a problem getting it connected that way. He is going to call me with the nema number of the cord cap he uses so I know exactly what he is dealing with... The way I plan on dealing with this is either 1. run a 50 amp circuit and tell him not to run so much equipment, or 2. run a 100 amp circuit and use somthing like Cam-loc or pin and sleeve connections. Does anyone have any other suggestions or pictures of set ups what they have done? thanks in advance!

oh yeah, he told me he has 18000 watts of equipment, and we are going to be feeding it from a 208/120v panel.

 

[Buck Parrish]

That 18000 is the maximum if every thing is turned wide open all at the same time.
I had a similar situation. They told me similar to what your guys are telling you. " We never had a problem doing it like that." So I did it and it worked fine. That's when I realized they we're useing the name plates to add up the watts. And they really werent useing half of what they thought they we're.

 

[ultramegabob]

I am going to have to figgure out what the correct thing to do is, I dont have any interest in putting a 50 amp recept on a 100 amp breaker and have some DJ crank up the volume and start a fire during a public event....

 

[Buck Parrish]

Yeah, I went around and looked at the name plates of all their equipment.
Then I stayed for the practice session. oouuccHH!!!
They probably only need a 50 amp breaker.

 

[fireryan]

we one time had a band tell us that they needed a 200 amp service for there set up. We installed a 200 amp temp service and all was good even though we thought it was a bit overkill. I found out the reason that they wanted a 200a service because the 2/0 cord they were using wouldnt fit on a 100 breaker so they figured that they must need a 200a service

 

[Buck Parrish]

Your right, When it comes to musical eqipment. The more amps you say have. It seems the equipment is better. Like the speakers in the back of your car. 3x9 jensens or pioneer " Oh that is 1000 watts" That makes it seem better.

 

[fireryan]

could you put in a 100amp disconnect and then just run his cord in there and do away with the cord end?

 

[LarryFine]

My HT system amplification totals 2200 watts continuous, but I doubt I've ever used that much from the service. Anyone want to lend me a power recorder?

could you put in a 100amp disconnect and then just run his cord in there and do away with the cord end?

You mean legally?

 

[fireryan]

My HT system amplification totals 2200 watts continuous, but I doubt I've ever used that much from the service. Anyone want to lend me a power recorder?

You mean legally?

what would be the violation there larry?

 

[walkerj]

Flexible cords cannot be used as permanent wiring.

 

[ultramegabob]

this cannot be a permanent connection anyway, the DJ must be able to make the connection and disconnect it himself, he travels around, this is not a permanent location for him. l

 

[iwire]

I am willing to bet all he needs is a two pole 50 but to him that is 50 + 50 = 100.

In any case I would not violate the code as night club fires have taken many lives

Also some areas require that sound systems be shut down by activation of the fire alarm system. If that is the case where this is a shunt trip breaker would be in order.

 

[gra electric]

I work as an audio engineer for a professional touring audio company as well as electrical work. We do venues from 5000 to 35000 people. Our rig which is rated peak at 65000watts. Continuous, or program runs at about 40% of that and that is very loud. The rest is for "headroom" for any short burst of energy required to produce music. Without that headroom a short peak could result in distortion which is very audibly noticeable. We tie into a single phase 100A disco at each venue and never have a problem.

That dj could have probably survived on a 30A and been just fine. Now if he has significant lighting than that is a different story. (100kw worth of lighting in concert level requires 3phase 400A at 208V)

 

[DanZ]

Just out of random, wild curiosity, do you know if he came up with 1800 from adding up the name plate electrical watts, or from adding the "equipment" watts. I know I'm not explaining it right, but think nameplate wattage vs 18 1000w speakers.

I had this conversation with a friend, who insisted his 120W RMS head used 120w of 120V AC. Turns out it's closer to 95VA @ 120V. That could add up pretty quickly.

 

[zbang]

(100kw worth of lighting in concert level requires 3phase 400A at 208V)

How do you get that? If it's decently balanced, 100kw total = less than 300a/phase. Granted, most lighting tie-ins are 400a, but you don't -need- that.

I also think the DJ added up all the nameplate wattages. For this sort of thing, I've become a fan of installing 50a2p RV-type receptacles and providing both a standard spider box for those that need regular outlets and an adapter to a 14-50R. Then tell the venue that if the band's plug doesn't fit either, call me.

 

[ultramegabob]

I am willing to bet all he needs is a two pole 50 but to him that is 50 + 50 = 100.

In any case I would not violate the code as night club fires have taken many lives

Also some areas require that sound systems be shut down by activation of the fire alarm system. If that is the case where this is a shunt trip breaker would be in order.

I absolutely will not do anything that I know is a violation, and I feel that this is potentially a hazard to life and property, I have a feeling that I am not going to get the job, he was supposed to call me back and give me the nema number on his cordcap that he uses and so far no call.... I have a feeling he will try to find someone else to do what he wants, I am going to contact the building owner monday and give him a heads up on what they are wanting done, I may give a call to the electrical inspector as well.... if by chance I do get a call back from him, and he is using a range cord, all I will install is a 50 amp circuit, I dont need this job bad enough to gamble with safty.....

 

[gra electric]

How do you get that? If it's decently balanced, 100kw total = less than 300a/phase. Granted, most lighting tie-ins are 400a, but you don't -need- that.

When you figure all the mover lights, and theatrical lighting that goes along with most concert lighting systems you get pretty close to the 400a rating. I actually mispoke as most concert lighting rigs are typically 120kw (120*1000watt par cans) If it is perfectly balanced it would be over 300 per leg. Add onto it all the backstage safety lighting, plus any off the wall stuff the lighting director wants to add it gets seriously close...So yes you do need a 400a tie in, because if the lighting rig went down mid show my but is without a job...lol

 

[mivey]

I work as an audio engineer for a professional touring audio company as well as electrical work. We do venues from 5000 to 35000 people. Our rig which is rated peak at 65000watts. Continuous, or program runs at about 40% of that and that is very loud. The rest is for "headroom" for any short burst of energy required to produce music. Without that headroom a short peak could result in distortion which is very audibly noticeable. We tie into a single phase 100A disco at each venue and never have a problem.

Ignoring pf and taking 240 instead of 208 to get the lowest amps:

65,000 watts / 240 = 271 amps
40% of that (the continuous %) = 108 amps

How do you get by with 100 amps, single phase?

 

[ultramegabob]

Update...

Update...

I never got a call back from the customer with the NEMA numbers, and they didnt return my message when I called to check on it. A couple weeks ago I saw an advertisment for a show that was going on in the location, so I figgured they must have found someone that was willing to do the illegal installation that they wanted, so I made a call to our inspector and told him what to look for, I ran across the inpector today and he told me that he checked it out shut them down last week:grin:

 

[scwirenut]

this is simple, he has a 50amp range cord, probably 3 wire..thats feeds his distribution box. every small time band in the world has one, this very common. these guys are figuring their watts from the secondary of their power amps. these run at 26 volts. dont be scared when he says 18kw. just run a 6/3 on a 50 amp breaker with a regular 3 wire range outlet. . he'll do the rest. .... if it turns out he does have a 4 wire plug ( rare) then you will already have the 6/3, just change the device. most of these guys have a 4 wire to 3 wire converter anyway.