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Getting power? 50 Amps? is being discussed in the ControlBooth Lighting and Electrics forum; I was just pondering how you guys set-up for gigs or the such, for example some kind of reception or ...

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    Default Getting power? 50 Amps?

    I was just pondering how you guys set-up for gigs or the such, for example some kind of reception or event in ballroom or something. (Okay my examples are terrible. What I mean is, let's say you gotta do something, all rented gear. Where do you plug in your gear? Presumably you won't be using 3-4 20amp circuits. Can you guys go to some kind of panel where they might have some kind of industrial receptacle, for, I don't know, say 60 amps? That's respectable for a small gig, right? Just curious what the custom is for these types of gigs, and getting power for them.

    Charlie

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    Default Re: Getting power? 50 Amps?

    If the venue was built for events it should have a company switch (or 6). A company switch is a place for road shows (or one offs) to get power. When refereeing to a company switch it is understood that it’s 3 phase power. Think of it as a big breaker that the show can tie into. The two main ways to tie in are Cam Loks and bare ends. Cam loks are high amperage plugs (up to 400 amps each phase) and bare ends are just that.

    If the venue dosn't have a company switch most people head to the kitchen and try and find some high amperage service lines to plug into.

    Becasue everyone likes pictures http://www.unionconnector.com/cswitch/gallery.html

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    Default Re: Getting power? 50 Amps?

    Depending on the hotel, convention center, event hall, etc... you have no idea what you are going to get. Most hotels have a 60 or 100 amp panel that is mounted on a piece of plywood and has receptacles mounted all around it. They are 2 or 3 phase, and each receptacle is usually a 20amp circuit. they plug in to a plug that often looks like a big clothes dryer plug.

    Others will use a twistloc plug system, usually a L620 (or many call it a 2120) system with "dog houses", which have a set of standard 20amp plugs on them.

    Few will have actual "lug" power. These are usually available in 200 or 400 amp services. These are not common in smaller venues, but common in large.

    Don't forget, it costs money to tap into these. A recent hotel job that I did cost me $450 for a 60 amp service. Lug power at the LasVegas Convention Center is about $1200 per day.

    To be flexible, I used to have a 12 channel, 1.2k dimmer rack that was wired to 6 edison plugs. It allowed me to plug them into the three phase systems that I usually get, with one into it's each 20amp circuit. I just sold this on ebay and bought two of the Leprecon ULD dimmer packs.

    To be honest, it will be different at each venue.
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    Default Re: Getting power? 50 Amps?

    As was said, usually there is a wonderful panel all ready to be tied into, just need some sort of Power Distro system and your ready to go (well, assuming you or someone else are qualified to do the tie in).

    If no company switch, go look for the breaker boxes, figure out what is where, figure out how much is free. Go get the electrical drawings for the space, figure out what panel has enough unused power in it.

    I had to do something like this for a show I recently did. The wig and makeup department needed 16kw of power for hair dryers and whatever else wig and makeup people use. We ended up finding an unused panel in the basement of the theater, checked the blue prints, found where it was run to, decided that it was indeed safe, and tied a small sensor rack with non-dim cards into the panel (it happened to be single phase, so we had to switch the sensor rack to single phase). From there we ran one multi cable up to where wig and makeup needed the power.


    I've also done shows scrounging 20 amp outlets around, figuring out what is tied to what, taping up extra outlets so no one tries to plug anything else into them........... but that sound be avoided if at all possible.
    www.ZacharySpitzer.com

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    Default Re: Getting power? 50 Amps?

    Generator power is really not as expensive of an option as you would think. I have rented the big caterpillar trailer generators for a few shows. To be honest, if you are charged for power at the venue and need to hire an electrician to tap into a panel, it is probably cheaper.
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    Default Re: Getting power? 50 Amps?

    Stanton is correct. Sometimes you have to pay a flat rate for a "tie-in". let's say $6-12 / amp < it's sort of a sliding scale> so at times getting a generator < jenny> is a lot cheaper, even if you do have to pay a babysitter. Convention centers, meeting facilities will almost always have as others have stated, Hubbel, Cam-Lok, or L120 plugs availible. If not, Break out the sniffer and start looking for dedicated circuits.
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    Default Re: Getting power? 50 Amps?

    I just wanted to take a moment here to publicly kick myself.
    As I mentioned in a previous post I'm in currently reading Gillette's Designing With Light cover-to-cover. The section of the book that explains electrical distribution, company switches, etc. was one page further than my bookmark. Go figure. Maybe I'll read the rest of this book before I post any more?

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    Default Re: Getting power? 50 Amps?

    Quick story....any mind? Good!
    Once upon a time...
    I was setting up a pool side Luau for a corporate customer of mine followed by a dance party on the pool deck at the Hilton at Myrtle Beach, SC. I ordered a 100 amp service (it was the biggest they had) for lighting and found 2 open 20 amp circuits for sound. (The band provided sound, we just did the truss and lighting.....the pic is before we raised the truss, the wind was too strong right then to raise the truss just yet)

    We couldn't begin set up until 3pm for an 8pm show, so we had little time to set up. I got there, my guys started putting the truss up and hanging lights, and I put my multimeter on the power distro that they had for me. We had a problem, only one phase had power and I was getting 50volts on the ground and 80 volts on the neutral. I asked to talk to the electrician and we went to the panel room. He had it hooked up very wrong, (I still can't figure out what he did), but the electrical room was under the pool side bar and had more than 8" of water on the floor. He said that it was like this everyday, as the room was below sea level. He was hooking up the cable to the breaker on a hot panel with the front cover off as he was standing on a cinder block that was standing on its ends. It was ridiculous and one of the more unsafe things that I have seen.
    I don't remember the cost of that service, but I think it was about $300 for 100 amps, but it was not 3 phase.
    Attached Thumbnails Attached Thumbnails Getting power?  50 Amps?-luau.jpg  
    Last edited by stantonsound; June 11th, 2007 at 09:42 PM.
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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by stantonsound View Post
    Quick story....any mind? Good!
    Once upon a time...
    I was setting up a pool side Luau for a corporate customer of mine followed by a dance party on the pool deck at the Hilton at Myrtle Beach, SC. I ordered a 100 amp service (it was the biggest they had) for lighting and found 2 open 20 amp circuits for sound. (The band provided sound, we just did the truss and lighting.....the pic is before we raised the truss, the wind was too strong right then to raise the truss just yet)
    We couldn't begin set up until 3pm for an 8pm show, so we had little time to set up. I got there, my guys started putting the truss up and hanging lights, and I put my multimeter on the power distro that they had for me. We had a problem, only one phase had power and I was getting 50volts on the ground and 80 volts on the neutral. I asked to talk to the electrician and we went to the panel room. He had it hooked up very wrong, (I still can't figure out what he did), but the electrical room was under the pool side bar and had more than 8" of water on the floor. He said that it was like this everyday, as the room was below sea level. He was hooking up the cable to the breaker on a hot panel with the front cover off as he was standing on a cinder block that was standing on its ends. It was ridiculous and one of the more unsafe things that I have seen.
    I don't remember the cost of that service, but I think it was about $300 for 100 amps, but it was not 3 phase.
    Should we assume you are the guy in the background with the lei?

    On a serious note, am I the only one that absolutely abhors the look of the aluminum/chrome/silver PAR cans? Too shiny. I'd rather matte black any-day. It does look a little better against the aluminum truss. But I still think it looks "cheap". Or, am I just crazy?

    Edit:
    Another quick question, that 360Q. Is that a 6x16, or 6x22? I asked this question before, but didn't have an accurate picture, just want to double check.

    Edit Edit:
    Out of curiosity, as it looks like a stormy day, what is the general procedure for rain and lights outside? You just pull the cords real quick and then lower your gear real quick and try and get it to a dry place, or is it okay in the rain, as long as there is no power, or what?
    Last edited by Charc; June 11th, 2007 at 10:29 PM.

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    Default Re: Getting power? 50 Amps?

    This show was September 2004, as the date in July was canceled due to a Hurricane.

    Question 1: Fat dude, white shirt, lei on, yup....that's me

    Question 2: I love chrome par cans. It isn't rock and roll without them.

    Question 3: I believe it was a 6x22. I love using gobos. We had the arches on the building, and a whole bunch of "I'm lovin it" on the pool deck from the truss towers around the pool. There was a red "I'm Lovin It" in the bottom of the pool (note the two leko's with a gold and red gels) I'll post a pic below.

    Question 4: It was a little wet. We were using truss mounted dimmer packs. I carry a bunch of the really big zip loc bags (5 gallon?) and put the packs in the bags and hung them under the truss. When I worked big concerts in college (local crew), the techs would power all of the cans, etc... to full before it would start raining and the water would evaporate off. I am not recommending it, but it is what they did. It never really rained, just a sprinkle and overcast.

    We used less lighting than was planned due to the wet weather. We didn't use any movers. All told, on the stage we only used:

    6 S4 Pars
    3 Ellipsoidals
    4 Par 64's
    8 Par 38's

    Then each truss tower had 1 6x12 with a gobo and 2 Par 64's.
    Attached Thumbnails Attached Thumbnails Getting power?  50 Amps?-backviewmainstage.jpg  
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    Default Re: Getting power? 50 Amps?

    Pictures will probably help.
    Here is an example of a Company Switch.

    Here's a 200a 3 phase distribution box with 24 - 20 amp weatherproof recepticals.

    Hope this helps.
    Thanks,

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by stantonsound View Post
    This show was September 2004, as the date in July was canceled due to a Hurricane.
    Question 1: Fat dude, white shirt, lei on, yup....that's me
    Question 2: I love chrome par cans. It isn't rock and roll without them.
    Question 3: I believe it was a 6x22. I love using gobos. We had the arches on the building, and a whole bunch of "I'm lovin it" on the pool deck from the truss towers around the pool. There was a red "I'm Lovin It" in the bottom of the pool (note the two leko's with a gold and red gels) I'll post a pic below.
    Question 4: It was a little wet. We were using truss mounted dimmer packs. I carry a bunch of the really big zip loc bags (5 gallon?) and put the packs in the bags and hung them under the truss. When I worked big concerts in college (local crew), the techs would power all of the cans, etc... to full before it would start raining and the water would evaporate off. I am not recommending it, but it is what they did. It never really rained, just a sprinkle and overcast.
    We used less lighting than was planned due to the wet weather. We didn't use any movers. All told, on the stage we only used:
    6 S4 Pars
    3 Ellipsoidals
    4 Par 64's
    8 Par 38's
    Then each truss tower had 1 6x12 with a gobo and 2 Par 64's.
    I think I spotted one of the ziploc bags on the right side of the picture. Looks like a great setup. The gobo on the column, from the 6x22 looks like it worked really well, and I bet the red ERS aimed at the pool looked really good too. Nice work. (Nice lei too. )

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    Default Re: Getting power? 50 Amps?

    I'm going to jump in here and remind everyone that power taps like this are right on the edge of electricians territory. My college is great and has installed cam taps in nearly every venue my club works and makes sure they all have proper disconnects, knowing that this is FAR safer than any other way practically available. Doing bare tales or hooking into a panel is something that needs to be done by an electrician, and even cam should only be done once you have been trained on the proper procedure for connecting cam.

    To elaborate abit more about WPI, we are really lucky to have a pair (usually one 120 amp and one ~200 amp) in each of the major venues where we host events. We generally use one for sound and one for lighting to keep things as separate as possible. We also have a firm procedure in place for connecting and checking the connections, as well as warning everyone when the power is turned on and when it is off. With these procedures in place we have had no major incidents with power in recent years!
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    Default Re: Getting power? 50 Amps?

    And this is where I love being an Aussie. Most of the time, you rock up with your dimmer and plug straight into the conveniently provided 5 pin, 32 amp three phase outlet. 40 or 50 amp outlets also greatfully received. 63 amp are physically much bigger and hence need an adaptor. 10, 15 and 20 amp sockets are physically smaller and also need an adaptor, and careful thought so you don't overload them.

    This is a 50 amp Clipsal outlet a la the type in question:

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by Chris15 View Post
    And this is where I love being an Aussie. Most of the time, you rock up with your dimmer and plug straight into the conveniently provided 5 pin, 32 amp three phase outlet. 40 or 50 amp outlets also greatfully received. 63 amp are physically much bigger and hence need an adaptor. 10, 15 and 20 amp sockets are physically smaller and also need an adaptor, and careful thought so you don't overload them.
    This is a 50 amp Clipsal outlet a la the type in question:
    "A la" the type I'm sure I've never seen before in my life. I don't think we have anything like that over here. The CamLocks (taps?) look like a pretty good option. After finding out more about it though, I do agree with everyone, that this is not something to be tried lightly. I just figured if perhaps it was standard practice to leave 30 amp circuits open anywhere (this sounds stupid now that I write it...) I'd like to find out where...

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    Default Re: Getting power? 50 Amps?

    Just to add my .02

    Large venues like was said have company switch or disconnect, typically 200 or 400 amps and 3 phase, and as described usually has bare ends or cam loks

    Lex makes a very nice three phase 100 amp distro. Be aware that the cost of the feeder cables can be more than the distro.
    Generators are great, BUT getting the feed into your venue location and having the subsequent distro to provide these feeds.

    the danger area is that in between when you start looking around for somewhere to plug in. I agree the Kitchen is the usual place to go, BUT you need to be very careful. There are (in the us) still lots of plugs in kitchens typically used for fryers that you will see, problem is a lot of these are three prong plugs. Reason is that typically these devices simply used the two hots, and.... here is where it gets dangerous, some the third is neutral, sometimes it is the ground. Some people will just connect the neutral and the ground together at this point, but again this can be dangerous, since the code is that there should be only ONE point where the ground and neutral are bonded together and that is at the service entrance. A lot of the old timers call these connections the dryer plug ghetto distro connection. ;-)

    IMO you are better with a few other options, on is get your self your own disconnect, in the 50 amp area, there are lots of relatively inexpensive spa or pool disconnects, have the disconnnect wired into the panel.

    The other option is to buy your self a square d QO or Siemens breaker usually around 60 amps two pole along with your setup, that way if there is not an empty unused breaker in the panel, typically the panel will be one of the two breakers and you can get them to add the breaker into the panel for you and connect you up.

    All this is of course typically with venues that are "friendly" to event providers
    Sharyn

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    Default Re: Getting power? 50 Amps?

    In reference to the raining/storm question. Where I'm located (northeast) we just crank all the cans up to full and let them bake off the water. Works very well. In one instance we cranked the truss down and wrapped it with plastic because it was one of the old trusses that had dimmer sticks pre-installed and we really didn't want those to get soaked.

    If we think its going to rain, we typically will bag any major connections (feeder, mults, etc) even though they are suposed to be water proof. Any movers that might get wet are typically struck, depending on who the equipment supplier is and how difficult it would be to pull them out of the air.
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    Default Re: Getting power? 50 Amps?

    For rain, snow, any precipitation you can just let it evaporate off. This works fine with movers. You just cant power em down till its dry.

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    Default Re: Getting power? 50 Amps?

    Hmmm. The "water-bake-off technique" (if you will), is a pretty ingenious system for keeping your gear dry. The one thing I don't quite understand about that system is, let's say you are trying to light some kind of more intimate dance space at one of these functions; perhaps you are running your fixtures at 40%. It starts to pour, the crowd doesn't care, and continues to dance. You want to save your gear, so you bump up the fixtures to full. Doesn't that kind of ruin the atmosphere you had created? Wouldn't the crowd get angry, if they were having fun, and you started blinding them?

    Does the crowd usually run for cover, or do you guys just not care about the crowd anymore?

    Just curious.

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    Default Re: Getting power? 50 Amps?

    Hmm, again. I was looking at some power distribution systems online, after getting inspired from this thread. I cam across this picture, and I want to take a stab at it, to see if I'm understanding this:



    So NEC states that Black is hot, while white is neutral, and green is ground. So in this picture we see the mains connection in the back (normally this is covered by a plate that says "Danger; High Voltage", it's not normally exposed.) So I'll presume that the two rows of receptacles are for, lack of better words two separate "Power Outs". I'll go ahead and guess the not covered green connector is ground. The N must stand for neutral, and all three hot legs (right term?) are sharing a common neutral. So then it looks like three separate hot legs (that can't be right, it sounds too funny) are for... three phase power? (I'm not sure I'm getting the three phase power conceptually.) Other than that I can't think of a reason why you'd need three separate hot legs.

    Did I get the rest of that though?
    Last edited by Charc; June 13th, 2007 at 12:06 PM.

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    Default Re: Getting power? 50 Amps?

    Correct, Green is ground(earth)
    Let's have a little test.
    What do you connect first when tying in with cams?
    Philip LaDue
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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by avkid View Post
    Correct, Green is ground(earth)
    Let's have a little test.
    What do you connect first when tying in with cams?
    Haha, are you insane? I'm no where near qualified to tie in with cams.

    For the sake of answering the question, I'm prepared to be hypothetically electrocuted. We'll I'd have to hazard a guess that the first thing I'd connect is the ground, to make sure the hypothetical me is never the path of least resistance.

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by charcoaldabs View Post
    Haha, are you insane? I'm no where near qualified to tie in with cams.

    For the sake of answering the question, I'm prepared to be hypothetically electrocuted. We'll I'd have to hazard a guess that the first thing I'd connect is the ground, to make sure the hypothetical me is never the path of least resistance.
    Good guess. Now the cool thing. New Panels like the one you posted a picture of, have an interesting safety interlock. you can't open the little cover till the previous lead is installed. Most < ok, a lot> of the newer disconnects out there also have gone to the new NEMA standard of having 2 < two > neutrals. As you observed earlierin a standard 3 phase camlock panel al three pahases are sharing a common nuetral. This new style panel releives some stress on that circuit. < and sells more cable, camlocs, and panels.>



    In response to one thing mentioned earlier, Peter, This is not "sort of" getting into the realm of a "real" electrician. This is the realm of a real electrician. Tie-ins and disconnects should not be performed by anyone who is not properly trained and licensed. Most state have a MINIMUM requirement of being an LME < limited Maintenance Electrcian> license holder before you can even take the screws out of a panel to do a tie in. In Portland you are "supposed" to be an LME prior to connecting cam-loks into a company switch. Lets make it Very Clear children. Electricity can kill you dead. Even a 60amp sub panel in the woodshop has the ability to roast your eyeballs right outta your skull. As for cam-loks I once lost half of an EDI 48 touring rack because one of my "kids" from the shop decided to help out during an out. She just started disconnecting, the ground first, then the neutral........ Luckily it was only the pack that fried.
    < I hated that pack anyway it weigh 600 pounds.> < But I didn't tell her that!>
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    Default Re: Getting power? 50 Amps?

    Many of the installs are now going with a system that will not allow you to open the cap on the cam lok if the system is energized. There is usually a requirement now to have posted right there the proper connect and disconnect sequence.

    Van's experience is a classic example of how to have a disaster. NEVER EVER REMOVE THE NEUTRAL FROM A HOT CONNECTION, THE SAME GOES FOR GROUND.

    For the sake of education, when connecting, on a standard setup go from right to left, first connecting ground, then neutral then each of the hots, all with the power off.

    to disconnect, power off, again typically going from left to right, disconnect each hot, then neutral then ground.

    Sharyn

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by SHARYNF View Post
    NEVER EVER REMOVE THE NEUTRAL FROM A HOT CONNECTION, THE SAME GOES FOR GROUND.
    So, in an example "from the world"....

    A 24x2.4kW Sensor Rack and a 6x6kW Sensor Rack tied into a 400amp company switch. Tails to Tees to two short runs of feeder to the two racks. The cables had to be routed under the corner of a showdeck (with the cams right at the upstage edge of the deck--ie, not hidden by the deck).

    SOMEHOW, something go put down on the neutral tee, and caused it to rotate just enough that it was completing the circuit but not "locked".

    When there would be a lot of traffic at that corner of the deck it would wiggle the connection.

    Our first indication that something was wrong was a twofer that melted like a cannon fuse. Then the lights on those racks all stopped working. I started metering power at the racks. At the 6kW rack: L1 to N was giving me ~200v, L2 to N was 60-80v, L3 to N was ~120v. N to G was ~80v. At the other rack things seemed fine, but nothing would turn on.

    It took a while to figure out exactly what had happened--tech was still happening around us.

    Disconnecting the neutral is not only VERY dangerous (potentially to people, and apparently twofers!) when the system is energized, it will cause lots of weird things to happen.

    --Sean
    Sean R. McCarthy

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    Default Re: Getting power? 50 Amps?

    Jezza,

    Do you know John Carver?
    Thanks,

    Bill Cronheim - ESC, Inc.

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by SHARYNF View Post
    For the sake of education, when connecting, on a standard setup go from right to left, first connecting ground, then neutral then each of the hots, all with the power off.
    to disconnect, power off, again typically going from left to right, disconnect each hot, then neutral then ground.
    Sharyn
    I've seen many panels with the gound on the left, so I would disagree that it is "standard" to connect right-to-left
    A safer way of putting it might be:

    Connecting: Start with the ground, and work accross
    Disconnecing: Start at the opposite end from the ground, and work accross, ending with the ground
    -Fred

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by fredthe View Post
    I've seen many panels with the gound on the left, so I would disagree that it is "standard" to connect right-to-left
    A safer way of putting it might be:
    Connecting: Start with the ground, and work accross
    Disconnecing: Start at the opposite end from the ground, and work accross, ending with the ground
    -Fred
    And some gear/boxes have soft tails....

    Green/ground is ALWAYS connected first.
    Then white/neutral
    Then the three hot legs

    Disconnect in reverse order. Then the panel layout is irrelevant.

    --Sean
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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by BillESC View Post
    Jezza,
    Do you know John Carver?
    Was that directed to me?

    No, I don't. Why do you ask?

    --Sean
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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by Sean View Post
    Green/ground is ALWAYS connected first.
    Then white/neutral
    Then the three hot legs
    Disconnect in reverse order.
    That's exactly what I was getting at with my earlier "test" question.
    Philip LaDue
    9 year member.

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by Sean View Post
    And some gear/boxes have soft tails....
    Green/ground is ALWAYS connected first.
    Then white/neutral
    Then the three hot legs
    Disconnect in reverse order. Then the panel layout is irrelevant.
    --Sean
    I agree, my point that I did not make clear was that some of the newer systems have interlocked caps, layout is relevant and forces an order

    Sharyn

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    Default Re: Getting power? 50 Amps?

    A lot of the new company switches I see have no caps but have the connections behind a door (with a feed through on the bottom) which cannot be opened while the switch is on. Another interesting tidbit to remember is that the ground and neutral cams should be reverse gender from the hots so they can't be crossed.

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by Sean View Post
    Was that directed to me?
    No, I don't. Why do you ask?
    --Sean
    Nope, I was asking Jezza.

    Has anyone come across an old main panel using stick fuses where the neutral also is fused? Happened to me and was a very long two days and a very long story.
    Thanks,

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by BenFranske View Post
    Another interesting tidbit to remember is that the ground and neutral cams should be reverse gender from the hots so they can't be crossed.
    That is up in the air, while it is a good idea in my book this would have to be a universal thing otherwise the amout of adapters needed will make this counter productive. WE are almost done with 3 pin DMX cable after 10 years, the move to flipped G+N might take twice that as the cost per conector is greater.

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by BillESC View Post
    Nope, I was asking Jezza.

    Has anyone come across an old main panel using stick fuses where the neutral also is fused? Happened to me and was a very long two days and a very long story.
    Fused Neutral ? That's Weird! What's the point ? If you fry that leg and you don't fry one of the hot legs, you're goona be in for a world of hurt.
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    Default Re: Getting power? 50 Amps?

    Yes, Van, thank you for clarifying that. The only part of this that is not treading into electrician's terratory is the connecting / disconnecting of cam. This can be done by a non-licenced electrician with proper training.

    About the flipped gender ground / neutral, we recently found out that that is quite a standard practice "out west" according to several rental houses and distro manufacturers in our area, and most of the eastern seaboard uses all of one gender on a device. We found this out the hard way when a new distro we ordered came with the ground and neutral's genders reversed. We simply bought two "gender benders" and always keep them with that distro and run the rest of our equipment with all connectors the same gender on any given device.
    [b]Peter[/b]

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by soundman View Post
    That is up in the air, while it is a good idea in my book this would have to be a universal thing otherwise the amout of adapters needed will make this counter productive. WE are almost done with 3 pin DMX cable after 10 years, the move to flipped G+N might take twice that as the cost per conector is greater.
    It seems to be an East coast/ West coast thing. Most of the lighting gear, on the East coast has H&N reversed. This has been the case for at least 10 years. There are already countless "turnarounds" floating around (and MMF or MFF tees can be used as well).

    --Sean
    Sean R. McCarthy

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    Default Re: Getting power? 50 Amps?

    Its more of a rock vs. film thing.

    Rock reverses the G+N because installs are quick.

    Film uses Etape to mark the colours on the legs and does not worry about the colour of the cams. Thus it makes it simpler to not have them reversed.

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    Default Re: Getting power? 50 Amps?

    Beware a Floating Delta! Had this in a club in PA once. All three legs measured 120 volts to neutral.. 3 Phase Y right? Nope! A separate feed that handled air, it was a delta box (240 between hots) with no neutral tap on the transformer! (As compared to the tapped delta 120/120/208) When a leg was loaded, it would go to 0 and the remaining legs would go through the roof! (I had to climb the pole outside to figure this one out.) There was a second feed for another mains panel coming in that was standard 3 phase Y (120/120/120 208-208-208) So the tip off was the 120 to ground but 240 between legs and three legs in the box. Only one I ever ran across in 30 years! (BTW, I was using EDI dimmers, they seamed to laugh off the over-voltage! Shame they weigh more than a truck!)
    Now, on to "Tapping fees." Never ran into this, even though I did a lot of work down in the Philadelphia theater district. (Schubert, Academy, Forest, etc.) I have to qualify that statement as they were union houses that billed the promoter directly, so there may have been billings I did not know about. Around these parts they are known as "Theatrical Disconnects" for road shows. There were some locations that would charge for a "House Electrician" which was generally the guy that would sit at the bar and watch you do it. My guess is this varies from state to state. The worst were the club owners that would point to 20 amp wall sockets as you were holding camlocks in your hands! Education of venue owners was always the hardest part for me.
    To answer some of the questions posted on this thread, Three phase power uses the same size neutral because the power is happening at a different time on each leg with a phase lag between them. With an exactly balanced load, no current flows through the neutral. (This will never happen in real life!) As far as handling power, it's like rigging: If at first you don't succeed, don't do power taps! There is no room for error.
    As far as rain goes, "Danger Will Robinson!" I know, we have all had to do them, but until they invent a 400 amp GFI, it will not be safe. As for the equipment, Cover the moving lights first! They may get wet, work fine, and then three months later fail!

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    Default Re: Getting power? 50 Amps?

    Quote Originally Posted by JD View Post
    Beware a Floating Delta! Had this in a club in PA once. All three legs measured 120 volts to neutral.. 3 Phase Y right? Nope! ...................... but until they invent a 400 amp GFI, it will not be safe...........

    When i was a young know it all, as opposed to now when I'm a Mature know it all, I hooked up a dust collector to a plug in our new shop. Fired up just fine, then I touched it and got the crap knocked out of me. Yup is was an old mechanical warehouse / metal working facility where they used a lot of heavy machinery, all of it delta. FYI now days most good electricians will mark an outlet or switch with a triangle to let others know it is a delta feed and not 3 phase 120. As a good measure, always check every hot to hot, and neutral to hot. They should be 240,240,240,120,120,120, for standard 3 phase 240/120 or 208,208,208,120,120,120 for a 3 phase 208 or motor feed.
    Neutral to ground should be 0 if it's anything higher than 12v there is a good possibility that there is a floating nuetral, or reversed nuetral somewhere in the system.


    I actually used a 400 amp gfci for the dive scenes in Men Of Honor , Since we were on a dock with a lot of lights and we had folks in the water,around the water etc.etc we had to have this little unit in-line with our Jenny. it was about 2x2x2.5 feet and weighed a ton!
    Van J. McQueen
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    "The only Dumb Question is the one you don't ask."

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