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Title: nice power at the Hotel
Post by: Tim A Perry on December 13, 2010, 12:04:57 am
index.php/fa/34195/0/

In the past I posted some of the awful stuff I run in to. I was pleased to find this in the ballroom where I will be doing a light show on NYE.
Title: Re: nice power at the Hotel
Post by: Andrew Broughton on December 13, 2010, 02:46:08 am
Upside down edisons and no cams? Boo.
Title: Re: nice power at the Hotel
Post by: Tony "T" Tissot on December 13, 2010, 04:16:19 am
Looks like six 15 amp circuits.

I share your joy.

Seriously.
Title: Re: nice power at the Hotel
Post by: Milt Hathaway on December 13, 2010, 06:37:06 am
Andrew Broughton wrote on Mon, 13 December 2010 01:46

Upside down edisons...


Apparently that's the by-the-code way now.

Looking at the size of the connectors between boxes, I'll bet they only ran one neutral wire through that entire run of boxes. If I'm imagining correctly, they've got a minimum of 8 wires pulled through that first connector. Nice trick.
Title: Re: nice power at the Hotel
Post by: Jay Barracato on December 13, 2010, 07:33:29 am
The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.
Title: Re: nice power at the Hotel
Post by: frank kayser on December 13, 2010, 07:43:13 am
I don't know about you, but I've yet to find an angled plug on a refrigerator that did not point up in a normally oriented receptacle (ground down)

Jay's explanation sounds reasonable to me...

frank
Title: Re: nice power at the Hotel
Post by: Eric Simna on December 13, 2010, 08:03:58 am
Jay Barracato wrote on Mon, 13 December 2010 07:33

The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.


I can tell you, that from experience, ground UP is a great idea. When I was younger, and stupid, and my step father claimed to know more than he actually did, he built a bedroom in the attic, electrical included.  Well, he used metal cover plates, but forgot the screws to hold them in place.  Well one day I unplugged our space heater and the plate fell.  Shorting H-N.  It was impressive watching the lights dim to nearly nothing. No breakers tripped either.  

My mother promptly went out and bought plastic covers.

That might have been the day I became really interested in electrical work.  Partially to keep my stepfather from ever doing it again.
Title: Re: nice power at the Hotel
Post by: Greg Cameron on December 13, 2010, 12:55:15 pm
Jay Barracato wrote on Mon, 13 December 2010 04:33

The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.


I've actually witnessed this a couple of times. Once it was an unwound guitar string that
had been placed on a guitar amp. It fell off and landed right inside the gap between the amp's plug and the wall outlet. Nice short. The other time was a metal dongle tag for a USB license dongle for an Avid "Media Composer" video editing system. Avid, in their wisdom, decided to make the tags metal. The tag was hanging off of a USB hub sitting on top of a Mac G4 computer. It got jostled and the tag slide off the top of the hub on right into the gap between a power plug and the outlet. Almost started a fire as the short wasn't enough to trip the breaker right away. But it was enough to heat up the tag nice and hot to melt the plug and the wall plate. I guess I wasn't the only one who saw problems with this as Avid changed their dongle tags to plastic at some point.

Greg
Title: Re: nice power at the Hotel
Post by: Rick Stansby on December 13, 2010, 01:12:13 pm
Jay Barracato wrote on Mon, 13 December 2010 04:33

The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.


"upside down" edison plugs used to be a pet peeve of mine, but then someone explained what you have just explained, and now I prefer them "upside down".
Title: Re: nice power at the Hotel
Post by: John Roberts {JR} on December 13, 2010, 02:17:14 pm
OTOH during a flood the rising water would hit a ground lug down terminal first and harmlessly ground the water... While I concede this is a slender benefit.

JR
Title: Re: nice power at the Hotel
Post by: Scott Smith on December 13, 2010, 02:18:15 pm
Rick Stansby wrote on Mon, 13 December 2010 13:12

Jay Barracato wrote on Mon, 13 December 2010 04:33

The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.


"upside down" edison plugs used to be a pet peeve of mine, but then someone explained what you have just explained, and now I prefer them "upside down".

"Falling paper clips".... Shocked
Title: Re: nice power at the Hotel
Post by: Jeff Wheeler on December 13, 2010, 02:53:29 pm
John Roberts  {JR} wrote on Mon, 13 December 2010 13:17

OTOH during a flood the rising water would hit a ground lug down terminal first and harmlessly ground the water... While I concede this is a slender benefit.

Who knows what a rising flood might hit first.  It could be a conductor supplying the receptacle, and which one that might be is anybody's guess.

I have read some lively debate on the topic of which way to install receptacles.  I remain convinced that either way is okay, but I have a few appliances in my home that have angle cords which like to be plugged in "right side up."  I have never seen an angle cord meant for "upside down" operation.  Polarized wall warts support themselves against the faceplate, box, or wall best if they are plugged in "right side up."  If I was deciding which way to mount them myself, I would go with "ground down."  If I hired an electrician to do work for me and he put my receptacles in "ground up" I would not throw a fit.
Title: Re: nice power at the Hotel
Post by: Milt Hathaway on December 13, 2010, 03:11:02 pm
Jeff Wheeler wrote on Mon, 13 December 2010 13:53

John Roberts  {JR} wrote on Mon, 13 December 2010 13:17

OTOH during a flood the rising water would hit a ground lug down terminal first and harmlessly ground the water... While I concede this is a slender benefit.

Who knows what a rising flood might hit first.  It could be a conductor supplying the receptacle, and which one that might be is anybody's guess.



Of course, at a certain point it doesn't matter:

index.php/fa/34203/0/
Title: Re: nice power at the Hotel
Post by: dave tesch on December 13, 2010, 03:22:33 pm
when my home flooded with 9' of water the power stayed ON. the service panel (completely submerged) stayed ON. full power to entire house; in fact we powered the trash pump from house power to suck the water out. water is a lousy conductor of electricity, it almost doesnt conduct at all but the impurities in water do. apparently the water that flooded my home was clean enough that it did not conduct electricity even when submerging the service panel and entrance.

as per the "upside down" edisons, the ones mounted with ground pin DOWN are upside down. look at most other plugs/outlets in the code and they are ground pin UP.
Title: Re: nice power at the Hotel
Post by: Bennett Prescott on December 13, 2010, 03:26:41 pm
Wow. A picture is worth a thousand words.
Title: Re: nice power at the Hotel
Post by: Greg Cameron on December 13, 2010, 03:59:11 pm
dave tesch wrote on Mon, 13 December 2010 12:22

water is a lousy conductor of electricity, it almost doesnt conduct at all but the impurities in water do. apparently the water that flooded my home was clean enough that it did not conduct electricity even when submerging the service panel and entrance.


Sure, but who's going to stick their arm in to find out? lol... All it takes is one container of Morton's salt in the cupboard to get into the mix to create a lethal electrolyte. Back in EE school in college, I recall a lab where we tested conductivity of distilled water, vs. tap water, vs. either with a tiny pinch of salt. Average tap water was indeed a poor conductor of 120v house voltage though it did conduct somewhat. However, just a few grains of salt in a beaker was enough to turn it into a very good conductor. I certainly wouldn't want to chance a submerged building with known live juice in it. That open bottle of catchup you left on the coffee table eating In-N-Out french fries could be your undoing Wink

Greg
Title: Re: nice power at the Hotel
Post by: Gus Housen on December 13, 2010, 08:39:19 pm
Isnt a metal gang box gounded anyway so water would touch the grounded box anyway?
Title: Re: nice power at the Hotel
Post by: Randy Gartner on December 13, 2010, 10:41:46 pm
dave tesch wrote on Mon, 13 December 2010 20:22

when my home flooded with 9' of water the power stayed ON. the service panel (completely submerged) stayed ON.


If the breakers never tripped while the panel was fully submerged,it was probably a Zinsco or FPE.That's why they went out of bussiness.As far as ground up or down,it was never addressed in the NEC to my knowledge.As far as a metal cover falling off,I only have ever seen that once in 36 years as an electrician.In that case,the ground was up but it still shorted because it touched both the ground and the hot prong of the cord.
Title: Re: nice power at the Hotel
Post by: Jay Barracato on December 14, 2010, 10:08:53 am
Randy Gartner wrote on Mon, 13 December 2010 21:41

dave tesch wrote on Mon, 13 December 2010 20:22

when my home flooded with 9' of water the power stayed ON. the service panel (completely submerged) stayed ON.


If the breakers never tripped while the panel was fully submerged,it was probably a Zinsco or FPE.That's why they went out of bussiness.As far as ground up or down,it was never addressed in the NEC to my knowledge.As far as a metal cover falling off,I only have ever seen that once in 36 years as an electrician.In that case,the ground was up but it still shorted because it touched both the ground and the hot prong of the cord.




Or more likely the power was off further upstream before the panel was submerged.

edit- I just remembered being extremely frightened at Del Fest after the storm a couple years ago with a foot of standing water everywhere around the stage and no clue where the power lines were.
Title: Re: nice power at the Hotel
Post by: Clayton Luckie on December 14, 2010, 11:26:14 am
Milt Hathaway wrote on Mon, 13 December 2010 14:11

Of course, at a certain point it doesn't matter:
index.php/fa/34203/0/


That's not what I meant when I asked for "shore power".  Rolling Eyes

cl
Title: Re: nice power at the Hotel
Post by: Joe Brugnoni on December 14, 2010, 11:50:52 am
Damn, now I need to go to the bathroom Laughing
Title: Re: nice power at the Hotel
Post by: Silas Pradetto on December 14, 2010, 12:00:06 pm
John Roberts  {JR} wrote on Mon, 13 December 2010 14:17

OTOH during a flood the rising water would hit a ground lug down terminal first and harmlessly ground the water... While I concede this is a slender benefit.

JR


Pure water doesn't conduct, impurities are what make it conductive. Even in a conductive state, it still has a high resistance. I doubt a circuit would trip if submerged in water in most cases (unless GFCI protected), instead, an electrolysis effect might happen where the water starts to react.
Title: Re: nice power at the Hotel
Post by: Jay Barracato on December 14, 2010, 12:03:37 pm
The resistance of pure water is approximately 18 megaohm. In a lab setting the resistance is used as a measure of purity in distilled or deionized water units.
Title: Re: nice power at the Hotel
Post by: John Roberts {JR} on December 14, 2010, 02:11:01 pm
My tap water is running between 1M and 2M .

JR
Title: Re: nice power at the Hotel
Post by: Silas Pradetto on December 14, 2010, 02:35:26 pm
Jay Barracato wrote on Tue, 14 December 2010 12:03

The resistance of pure water is approximately 18 megaohm. In a lab setting the resistance is used as a measure of purity in distilled or deionized water units.


I just looked it up, since I never had before and had been going based on what science teachers and others told me.

18 megaohms certainly isn't completely non-conductive, but it is quite a high resistance. I wonder what the impedance graph of water looks like?

How is 18 megaohms measured? What distance in the water are we talking about? I'm assuming one would just dunk DMM probes in the water and measure? But wouldn't the resistance increase the farther the probes are apart, like with copper or anything else?

I'm interested now Very Happy

I'm going to do an impedance sweep of the shop's water tonight Laughing
Title: Re: nice power at the Hotel
Post by: Alan Sledzieski on December 14, 2010, 03:40:43 pm
Never could understand why anyone would want the ground up.  Cords hang down, if slightly pulled out the equipment ground would be lost first, yet the H and N still inserted.  So your still energized with no eq. ground.
Title: Re: nice power at the Hotel
Post by: Silas Pradetto on December 14, 2010, 03:44:26 pm
Alan Sledzieski wrote on Tue, 14 December 2010 15:40

Never could understand why anyone would want the ground up.  Cords hang down, if slightly pulled out the equipment ground would be lost first, yet the H and N still inserted.  So your still energized with no eq. ground.


I'd rather have my cord plug itself back into the overused, non-spec-grade receptacle and have the show continue than have it unplug because it has no more grip, and end the show.

The ground pin is longer anyway.

PS-Give me camlocks or a twistlock any day over wall plugs.

"But they were enough for this really big show we had in here last year"

Ha!
Title: Re: nice power at the Hotel
Post by: Milt Hathaway on December 14, 2010, 03:52:07 pm
Alan Sledzieski wrote on Tue, 14 December 2010 14:40

Never could understand why anyone would want the ground up.  Cords hang down, if slightly pulled out the equipment ground would be lost first, yet the H and N still inserted.  So your still energized with no eq. ground.


I'd rather have the ground connection resistance start to rise than have a current-carrying connection's resistance start to rise, especially under a heavy load.
Title: Re: nice power at the Hotel
Post by: David "Luke" Landis on December 14, 2010, 08:34:07 pm
Scott Smith wrote on Mon, 13 December 2010 14:18

Rick Stansby wrote on Mon, 13 December 2010 13:12

Jay Barracato wrote on Mon, 13 December 2010 04:33

The logic that was explained to me the first time I saw a contractor doing that was that if a paper clip or something was dropped on a partially inserted plug, it would hit the ground first and slide off, instead of potentially shorting the hot/neutral.


"upside down" edison plugs used to be a pet peeve of mine, but then someone explained what you have just explained, and now I prefer them "upside down".

"Falling paper clips".... Shocked

Metal Drum Brushes.....
Title: Re: nice power at the Hotel
Post by: Jeff Wheeler on December 14, 2010, 08:49:11 pm
Ground Fault Circuit Interrupter

I know how we all hate these things when musicians have broken gear they refuse to fix, even though they had the same broken shit that tripped GFIs last time you had them four months ago, and they know you remember it ... but IMO GFCI should be required for stage power.  I just wish everyone else agreed with me so I didn't seem like the crazy one!  Crazy is risking your life by handling some guitar rig that looks like, and probably did, just fall off a truck and produces that burning smell when powered on, instead of having a safety device that inconveniences people by making them repair their broke-ass gear.  $0.02.
Title: Re: nice power at the Hotel
Post by: dave tesch on December 14, 2010, 08:52:27 pm
Never could understand why anyone would want the ground up. Cords hang down, if slightly pulled out the equipment ground would be lost first, yet the H and N still inserted. So your still energized with no eq. ground.

try it. it aint gonna happen. if you look even with a quick glance you will see the ground pin is a lot longer than hot and neutral. the ground inserts first, and unless modified is the last to be removed.

if you can connect hot and neutral without connecting ground on an unmodified plug/outlet then you are amazing.
Title: Re: nice power at the Hotel
Post by: Phil LaDue on December 14, 2010, 09:47:12 pm
Gus Housen wrote on Mon, 13 December 2010 20:39

Isnt a metal gang box grounded anyway so water would touch the grounded box anyway?
I haven't seen a metal gang box in new construction in quite a while.
(exterior and service areas excepted)
Title: Re: nice power at the Hotel
Post by: jason misterka on December 14, 2010, 10:26:13 pm
Jay Barracato wrote on Tue, 14 December 2010 10:08



edit- I just remembered being extremely frightened at Del Fest after the storm a couple years ago with a foot of standing water everywhere around the stage and no clue where the power lines were.


Hey Bud -

Why worry?  I was more worried about getting blown away or hit by lighting.

The generator was disabled early on in the storm not turned back on until we traced all cable runs (power, speaker cable, motor cable, etc..) and made sure they were dry. Feeder was put on pallets where needed, though much of the feeder run was in grass instead of mud puddles since it was on the other side of the fence from the dancing hippies.

Did you not stay to see the 20 festival workers manning the 4 blow dryers for two hours to get us back up and running Smile  What a weekend...

Jason


Title: Re: nice power at the Hotel
Post by: Jay Barracato on December 15, 2010, 06:46:16 am
jason misterka wrote on Tue, 14 December 2010 21:26

Jay Barracato wrote on Tue, 14 December 2010 10:08



edit- I just remembered being extremely frightened at Del Fest after the storm a couple years ago with a foot of standing water everywhere around the stage and no clue where the power lines were.


Hey Bud -

Why worry?  I was more worried about getting blown away or hit by lighting.

The generator was disabled early on in the storm not turned back on until we traced all cable runs (power, speaker cable, motor cable, etc..) and made sure they were dry. Feeder was put on pallets where needed, though much of the feeder run was in grass instead of mud puddles since it was on the other side of the fence from the dancing hippies.

Did you not stay to see the 20 festival workers manning the 4 blow dryers for two hours to get us back up and running Smile  What a weekend...

Jason





Jason,

I weathered the storm in my trailer which has actually been through worse. I talked to you briefly onstage just as you were starting the cleanup process (I was with Gil landry at the moment). In hindsight, it really wasn't the stage area that had me worried but the hodge podge of cables and boxes in the camping area. To cross from the stage to the camping area you had to cross what was basically a small river that had a number of cables on the ground. Where they went or came from I am not sure, but they probably were not from your main generator.

Getting the rig back together and up for the last set of the night was probably one of the most significant and impressive acts of "the show must go on" I have personally seen.

I had a noon loadin that sunday back in Annapolis, so I cut out early Sunday and did not see too much of the cleanup.

Hope to see you again soon under better conditions.

Jay
Title: Re: nice power at the Hotel
Post by: David Buckley on December 26, 2010, 07:17:52 am
Andrew Broughton wrote on Mon, 13 December 2010 20:46

Upside down edisons...

My understanding is that there is no "right" way to mount an Edison; The NEC is silent on the issue.
Title: Re: nice power at the Hotel
Post by: Tom Manchester on December 26, 2010, 01:29:45 pm
Join my flickr group! It's dedicated to hotel power distros.

http://www.flickr.com/groups/1566167@N20/
Title: Re: nice power at the Hotel
Post by: Tim A Perry on December 26, 2010, 03:14:06 pm
index.php/fa/34417/0/

Here is one I took at a local party center. I swear on my boy scout handbook this is not a gag.
Title: Re: nice power at the Hotel
Post by: drewgandy on December 26, 2010, 03:29:02 pm
Tim A Perry wrote on Sun, 26 December 2010 14:14



Here is one I took at a local party center. I swear on my boy scout handbook this is not a gag.


Where do you tie in?
Title: Re: nice power at the Hotel
Post by: Alan Sledzieski on December 26, 2010, 03:54:38 pm
Tim A Perry wrote on Sun, 26 December 2010 15:14

index.php/fa/34417/0/

Here is one I took at a local party center. I swear on my boy scout handbook this is not a gag.



At least its labeled.
Title: Re: nice power at the Hotel
Post by: Tim A Perry on December 26, 2010, 03:55:02 pm
I don't know... we used LED lights into a wall outlet for this show.


index.php/fa/34419/0/

Here was a prep survey for the theater job.
Title: Re: nice power at the Hotel
Post by: Lee Brenkman on December 26, 2010, 05:46:10 pm
We're planning a "small" upgrade to this venue.

At least they kept the fuses clean Razz

index.php/fa/34425/0/
Title: Re: nice power at the Hotel
Post by: Jim Brooks on December 27, 2010, 11:00:56 am
I really like how the one hot wire coming into the panel loops to provide power for both legs in the panel.
KOOL!

Jim
Title: Re: nice power at the Hotel
Post by: Tim A Perry on December 27, 2010, 11:26:40 am
Jim Brooks wrote on Mon, 27 December 2010 11:00

I really like how the one hot wire coming into the panel loops to provide power for both legs in the panel.
KOOL!

Jim


I believe this is a 3 phase panel that is wired for single phase 220.

I hope some brave soul someday finds the breaker feeding this panel and replaces the cover. The rest of the 'switchgear' in this facility while old is intact.
Title: Re: nice power at the Hotel
Post by: Dave C(arugo) on December 31, 2010, 11:07:13 am
Doing a run of gigs with a function band for the last few days, and two days ago I ran into a nice 32amp 3 phase ceeform outlet, on the end of an appropriately sized 2 metre cable coming from a switched wallbox... installed behind 10 or so stacked folding rolling hotel banquet tables, in the storage room behind the hotel's stage, with no way of getting the cable out of the store-room into the ballroom without leaving the door open. The hotel insisted on leaving the fluoroescent lights in the storeroom on.

So even though the installation was electrically fine, it was not really thought through...

Last night a different hotel gave us 4 metalclad 13 amp sockets (UK type) behind the stage. First song in and we tripped the breaker. Some investigation ensued with the hotel staff and we found that we were on the same power feed as the 4 large 3phase space heaters that they were using to heat the ballroom; the total breaker capacity was 25amps. They then claimed that the fairy lights behind the stage were most likely the problem, and proceeded to unplug them as they were on the same feed that we were using.

Problems stoped after they unplugged the space heaters...

Hopefully tonight will be better, but I wouldn't bet on it....

Dave C.
Title: Re: nice power at the Hotel
Post by: Geoff Doane on January 06, 2011, 10:19:12 pm
This year's (and last) NYE was out of town at an older bar, but at least they have the power together (for my modest needs).  Having a 15-50 receptacle on stage is a treat.

index.php/fa/34634/0/

I just wish they had installed it on one side or the other instead of practically right in the middle of the stage.

GTD