Live sound question for you electricians out there...

Carny1122

Carny1122

Plugin Whore
Hey guys, I wasn't sure what forum to put this question in, so I stuck it here. If anyone's feelings are hurt by my doing so, eh, that sucks. Sorry :cool:

Anyway, my live sound company just bought a Crown XLS 5000 for $1000 B-stock on MF (I know, I know, I hate to support them, but $1000 with a $200 mail-in rebate for a $1600 amp? Can't pass it up....). We got it on the recommendation from a friend in the industry after having rented (numerous times) a Crown Macro Tech 5000 VZ2 off of a buddy of ours (absolutely killer, killer amp, and he's got 12 of them!), and we wanted to buy a macro, only to realize that three college guys can't really afford one...


So to my point...Long story short, it's a 300 V circuit with a 20-amp fuse on each channel. Granted, it's probably never going to pull 20 amps out of a wall with situations that we have it in. As far as I forsee, we'll only have it (at most) halfway up for the next year or so until with relocate to a larger venue, which we plan on doing...Regardless, it's capable of doing so, so the ULS slapped a 20 amp fuse on it an voila, they throw my knowledge out the window and succeeded in thoroughly confusing me.

Basically, is there a way that I can purchase a 20-amp-load capable power conditioner, plug this S.O.B. in, and manage to plug the power conditioner into a regular wall with a 120V circuit? It doesn't seem to make sense to me, but that's why I'm askin! Also, the 300V cord's plug has a vertical, horizontal, and ground post(s) on it, so it won't go into a regular wall outlet without some sort of adapter. Even then, I'm worried it will trip he breaker immediately.


See I was just fine with 120V stuff and then I had to go and get this thing...damn.....

Also, the guy who we had been renting the macro 5000 off of put regular 2-vertical and 1-ground post plugs on all of his macros so that he could just plug them into any old wall outlet, and he said that he'd do it for us on the XLS 5000, but is that safe?

Not to be picky, I know that beggars can't be choosers, but it'd be awesome if someone who understood electrical stuff could simplify this down to a yes/no/there's no way in hell that will ever work type of answer scheme.

Thanks guys, and happy recording! :D
 
Carny1122 said:
Basically, is there a way that I can purchase a 20-amp-load capable power conditioner, plug this S.O.B. in, and manage to plug the power conditioner into a regular wall with a 120V circuit? It doesn't seem to make sense to me, but that's why I'm askin! Also, the 300V cord's plug has a vertical, horizontal, and ground post(s) on it, so it won't go into a regular wall outlet without some sort of adapter. Even then, I'm worried it will trip he breaker immediately.
Click to expand...


NO, you do not want to try that. Even if it's only half way up you are likely to be getting peaks that will draw over 20 amps. And that's assuming the wall outlet you plug into is a 20 amp outlet in the first place. You may not blow the breaker, but you also may. And of course, in the middle of the show, when you start to push the level up bit by bit, you're going to find yourself blowing a fuse at the most inconvenient times. Get a good power distro box with (at the very least) 100A three phase cam lock feeder input and pass through, a bunch of 20 amp Edison outlets (say, 12 on 6 circuits), and 5 or so 60 amp 5 wire twist lock circuits. Rack your amplifier in a box that hooks up to one of those 5 wire circuits. It's expensive, but doing it right saves you time in setup, makes the stage look cleaner, and makes the equipment work more reliably. Don't risk your shows by having crap power - power distros may not be as sexy as a power amp or mixing console, but in the final analysis it is WAY more important to have good quality power than anything else. You'll also need feeder cable and terminals to tie into the venues power - and unless you know what you are doing you REALLY want to hire an electrician to tie it in for you. It's not that it's hard, but it's easy to cause very serious damage if you do it wrong.

Next time, instead of spending that thousand dollars on an amp, spend it on a great distro and some feeder cable. You can always rent the amps, (or the power, for that matter, but I'd much rather have my own distro that I knew than an amp).


Light

"Cowards can never be moral."
M.K. Gandhi
 
300V circuit? Is this three-phase 100V each in Japan, or did the original poster make a mistake? The crown comes in four configurations: 100 VAC (Japan), 120 VAC (U.S.), 220VAC (various African and Asian countries including most or all of the former U.S.S.R.) and 230-240VAC (Europe). Some of those may actually be one configuration, and the supply might be switchable.

I'm assuming you mean that the amplifier has a 240VAC power supply and a 20 amp fuse, in which case it can draw up to 4800W off the power grid. If you got a step-down transformer, it would need to handle that wattage. Your circuit would also have to handle 4800/120, or 40 Amps. Bottom line is that no, there's no way you'd be able to handle that on a standard 5A circuit. You'd trip the breaker in about ten seconds. If you had a 10A circuit, you'd still trip it almost immediately. With a 20A circuit, you might be able to get away with it. Emphasis on might. Bear in mind that breakers (ground fault breakers notwithstanding) don't trip based on peak load. The overload has to be sustained to make it trip. That said, I probably wouldn't try it.

If, however, you mean that the device uses a 110VAC/20 amp fuse and you're asking if you can get by on a standard 110VAC 5A circuit... well, the answer is still no.

That's one obscenely high power amplifier....
 
Yeah, it's absurdly strong...

I really can't afford power distrobution stuff at this time, we're just three very broke college guys.

I don't have the amp with me at school (obviously), but lookin online, there are four different modes to run it (selectable or not, I'm really not too sure). 100V ~ 50Hz, 110-120V ~ 60Hz, 220-230V ~ 50Hz, and 240V ~ 50Hz.

The breakers on the back don't say if they're 20 amp or not, but I'm nearly positive that they are (it'd be nice to have the manual here, huh?).

Here's my logic....

they wouldn't make it if you couldn't use it. I just need to figure out how to use it.

Any simple (or simpler) options than power redstribution? I'm thinking that we're going to probably take it to the guy who we had originally been renting the macros off of...he's wise in the ways of sound. I trust him!
 
First off, the sideways prong on that amp desigantes a 20 amp plug. Many people do not realize it, but most all of the cords we use are actually only 15 amp rated. You will notice that often times you will see plug outlets, especially in commercial or business areas that have recepticles that are kind of combo where you can plug this type, and the regular 15 ampo type that we usually use in. you can get adaptors to convert a 20 amp plug down to 15 amp style which generally does not cause an issue because the breakers most everywhere are 20 amp now and all of the wiring inbetween is 20 amp capable.

The Fuhrman you listed is sort of similar to what is being talked about, but only incorporates 5 twenty amp circuits, and does not look like it has any sort of source cable.

As for getting an AC distro, if you are running a live sound company having a distro is a must. Not only is it convenient, but can also solve and help isolate a lot of grounding issues. As for getting a three phase distro, I would actually recommend against that and getting single phase unless you are running a HUGE sound system. Sound does not draw all that much AC and even a 100 amp single phase distro is capable of running shows of about 5,000 people at full rock volume. Three phase is certainly more capable, but if you are rolling into smaller venues, power is going to be much more complicated. I would reccomend a power distribution system like Light described above but in a single phase 100 or 200 amp setup. I would also reccomend getting a cam lock to 50 amp or 220 adapter. This makes power ties at a lot of venues very easy. Also consider that with single phase 100 amp systems your feeder does not have to be nearly as large, and you will be using 4 pieces of feeder as opposed to 5 pieces which cuts down on time, weight, and case size.

One other thing to consider, in real world application, unless you are running some very high wattage subs and a 2 ohm load, amps wide open, and driving them to their limit, the XLS 5000 will probably run all day long on a single 20 amp circuit unless it is also exposed to constant direct sunlight or poorly vented (heat build up can increase your chances of throwing a breaker if already running near the breakers threshold). I would reccomend making sure nothing else is running on the same circuit though as the XLS 5000 just for sanity sake. I would also still use the actual 20 amp plug whenever possible.

Getting a good distro is extremely important like light mentioned, but at the same time, to get a decent distro and even just 50 feet of mid gauge single phase feeder with cam locks (I would make sure you have at least 100' and even better 150' or 2 sections of 100'), you are probably looking at spending around 2 grand for the set up and a case.
 
Okay, very good to know.

Is it possible that you guys could maybe throw some links up to sites that (if not sell) have distro units? I'm definitely going to look into getting one (well, seeing as how that's my best option!)

Thanks for the help guys. I'll probably be looking into getting one over Christmas sometime...any recommendations on companies?

And I emailed Furman about that unit, and they never emailed back. Anyone else have trouble with their customer support?
 
You must log in or register to reply here.
Back
Top