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Author Topic: Preferred receptacle?  (Read 3468 times)

Stephen Swaffer

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Preferred receptacle?
« on: February 07, 2014, 11:47:34 pm »

 I was recently asked to install a receptacle to eliminate having to have an electrician (me) tie in when groups play at a local youth center.  I installed a 14-50R.  Sounds like everybody has there own preference-and wire cost may dictate the size distro one builds, but what do you prefer/hope to find?
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RYAN LOUDMUSIC JENKINS

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Re: Preferred receptacle?
« Reply #1 on: February 07, 2014, 11:52:38 pm »

I was recently asked to install a receptacle to eliminate having to have an electrician (me) tie in when groups play at a local youth center.  I installed a 14-50R.  Sounds like everybody has there own preference-and wire cost may dictate the size distro one builds, but what do you prefer/hope to find?

A fused disconnect, cam locks, a couple CS 50 amp twistlocks or a couple 14-50r are all good in my book. 
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Ray Aberle

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Re: Preferred receptacle?
« Reply #2 on: February 07, 2014, 11:56:40 pm »

A fused disconnect, cam locks, a couple CS 50 amp twistlocks or a couple 14-50r are all good in my book.
Same here. 14-50R is going to be pretty standard though-- someone who rolls with a distro used with that or generators will most likely have an adapter to hit that and go to their CS 50A twistlock setup. Renting spider boxes/50A feeder cable is easy to do if you need more power for someone who doesn't have their own gear. I would suggest that the venue (if they expect to do this often) have a range-to-gennie adapter on hand for spiderbox use. That won't be more then a hundred bucks to build.

-Ray




[I remember when I was young, and a hundred dollars was a LOT. Now, when I go spend multiple thousands of dollars at a time, and can go to a show with $50K-$100K worth of gear... sheesh. $100 is nothing. Haha.]
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Mike Sokol

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Re: Preferred receptacle?
« Reply #3 on: February 08, 2014, 08:15:59 am »

I was recently asked to install a receptacle to eliminate having to have an electrician (me) tie in when groups play at a local youth center.  I installed a 14-50R.  Sounds like everybody has there own preference-and wire cost may dictate the size distro one builds, but what do you prefer/hope to find?

A 14-50R in a box with a circuit breaker should be the minimum. I used these all the time in the 70's for my own band's distro since I could often find them as kitchen receptacles in crappy clubs. Two things to watch out for though. I would NOT just stick a surface mount 14-50R on the wall with unprotected wiring. That's certainly going to get any inspector's blood flowing. So make sure it's in a real metal box and fed by metallic conduit.

Secondly, anytime you plug into a 14-50R receptacle, meter it first to make sure it reads 240 or 208 volts between the hot legs. The reason for this is that I've encountered several of these in campgrounds that had the two hot contacts tied to a common phase. Seems stupid and certainly a code violation, but that's what you get when DIY volunteers do wiring. While any of your 120-volt gear will operate normally from that mis-wired outlet, the neutral currents will add rather than subtract, so the neutral wire can see up to 100 amps current. Running 100 amps through a connector and wire sized for 50 amps will create a melt-down. I have a picture of that fail somewhere and will post it when I can find it.

Adding cam-locks in the same box with their own 100-amp disconnect would be a nice addition and not too expensive. I think that a 100-amp 240-volt service with a 100-amp breaker on cam-locks (L1, L2, N, G), plus a pair of 14-50R receptacles each on their own 50-amp dual breaker would be great, and not break the bank. I would also install five Edison NEMA 5-20 receptacles in a row, each on their own 20-amp breaker. This would be one-stop shopping so any band could tie-in with heavy extension cords, stove plug, or cam-locks. I would think that with modern LED lighting and Class-D amps that you could run a pretty large show from a 100-amp/240-volt service panel with the above connections. Make sure you spec a 100-amp main breaker on this so that a combination of all the loads won't smoke the incoming circuit. Yes, I know you all know this, but I still see crazy stuff that's downright dangerous.
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Tim McCulloch

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Re: Preferred receptacle?
« Reply #4 on: February 08, 2014, 10:27:23 am »

Mike, are campgrounds/RV (caravan, for your Euro readers) parks all exempt from any form of inspections?  From the amount of work you do with these camping units and places I can't believe anyone would plug in at such facilities.  With the obvious problems they can create from a relatively simple distribution system, how do they not get sued out of existence and the campground owner's group not lobby to get member facilities up to snuff?

I was an electrician on a Family Motorcoach Assn. event.  Miles of 4/0 between generators and really big spider boxes, with extension runs available to exhibitors and attendees.  Not a single report of any problem that could be attributed to the temporary system, but several that were mis-wired shore power plugs on the coaches themselves.  Why would anyone spend $$$$$ on a Monaco or other Class A and then wire the damn plug themselves?  /rant
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"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut

Mike Sokol

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Re: Preferred receptacle?
« Reply #5 on: February 08, 2014, 02:02:25 pm »

Mike, are campgrounds/RV (caravan, for your Euro readers) parks all exempt from any form of inspections?

Yes, campgrounds are not required to have inspections and many times a campground will use somebody called a "workamper" to do wiring. A "workamper" is a DIY guy who works in trade for free camping space. There's no requirement that they're licensed in any way, and no test procedure or certification. And many campgrounds are being forced to add more 50-amp/240-volt outlets to accommodate the huge RV's now becoming popular. That combination of DIY labor and campgrounds wanting to take shortcuts causes a lot of grief.

Quote

I was an electrician on a Family Motorcoach Assn. event.  Miles of 4/0 between generators and really big spider boxes, with extension runs available to exhibitors and attendees.  Not a single report of any problem that could be attributed to the temporary system, but several that were mis-wired shore power plugs on the coaches themselves.  Why would anyone spend $$$$$ on a Monaco or other Class A and then wire the damn plug themselves?  /rant

Yes, those Class-A motorhomes start in the $100,000 range and go UP from there, many costing $250K to $500K. And the owners are so cheap that they'll rewire the plugs themselves or use a Home Depot extension cord instead of paying $100 for an RV rated cord. Yikes...

And these big RV coaches draw a LOT of power. So much so, that the RVIA (governing body of the RV manufacturers) is considering adding 100-amp/240-volt services for new coaches and campground pedestals. Don't know when it will all end, but I think it's a bad idea to be connecting to what's essentially house power while standing on the wet ground in the rain. Some campgrounds even tape over the circuit breaker in the pedestal so you don't wear them out which forces RV owners to plug in while "hot". More "Yikes"...

I have hundreds of emails like this in my file which is just crazy.
« Last Edit: February 08, 2014, 02:13:48 pm by Mike Sokol »
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Lyle Williams

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Re: Preferred receptacle?
« Reply #6 on: February 08, 2014, 04:22:38 pm »

Cam locks in a youth center sounds like a recipe for disaster...   :-)
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Mike Sokol

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Re: Preferred receptacle?
« Reply #7 on: February 08, 2014, 04:24:58 pm »

Cam locks in a youth center sounds like a recipe for disaster...   :-)

You're right. Put them in a box with a locked cover and only hand out the keys to serious sound crews with real power distro gear. That may be a code requirement in new venues.
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Ray Aberle

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Re: Preferred receptacle?
« Reply #8 on: February 08, 2014, 05:31:01 pm »

You're right. Put them in a box with a locked cover and only hand out the keys to serious sound crews with real power distro gear. That may be a code requirement in new venues.
It's been my impression that most venues already keep their cams under lock and key. Whether for safety of the personnel... or for the protection of their revenue stream. :D

-Ray
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Tim McCulloch

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Re: Preferred receptacle?
« Reply #9 on: February 08, 2014, 09:19:46 pm »

It's been my impression that most venues already keep their cams under lock and key. Whether for safety of the personnel... or for the protection of their revenue stream. :D

-Ray

http://www.unionconnector.com/company-switch/connection-chamber-switches

This design has shunt-trip on each Cam connector.  The master breaker cannot be turned to "ON" if all connectors are not mated (single neutral runs require a dummy plug), nor can it be energized if the connection chamber door is open.  The shunt trip can also be remotely activated (more safety interlocks or possibly revenue enforcement).

Similar products are made by others.  The LEX version has key locked access to all connections, IIRC.

I enjoy using these company switches.  Much safer that the old days of the big knife switches... and we have at least one local theater that has those.
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"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut
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