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Re: Vegas pole pigs can't take the heat (fwd)

---------- Forwarded message ----------
Date: Sat, 07 Jul 2007 17:00:22 -0700
From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Vegas pole pigs can't take the heat (fwd)

Ok David,

Don't call pigs "dinosaurs"!  That gets personal <grin>.  These 
dinosaurs still "ROCK THE WORLD" regardless of DRSSTC's, SISG's, bla, 
bla, bla, solid state stuff. RAW NARLY POWER == PIG! No contest! Throw 2 
SISG's at it and I'll throw 2 pigs at it. Guess who wins? Heck, you know 

Take care,

Tesla list wrote:

>---------- Forwarded message ----------
>Date: Sat, 07 Jul 2007 21:15:09 +0000
>From: David Rieben <drieben@xxxxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Cc: drieben@xxxxxxxxxxx
>Subject: Re: Vegas pole pigs can't take the heat (fwd)
>Hi guys,
>Wow, I got more info than I expected from this question ;^) Thanks to 
>everyone for their most informative inputs and thanks to Chip for his
>latitude of tolerance for a borderline OT subject that's beginning to drift
>completely OT ;^0  I think I now understand. The bottom line is that pole
>pigs still rock as power supplies for large, archaic "dinosaur" SG driven 
>coil systems. I'd like to eventually take the leap into DRSSTC land, but I
>consider myself just too electronically challenged as well as financi-
>ally challenged to seriously take on a megalythic solid state coil system
>at this time. BTW, both my 15 kVA pig that powers my Green Monster
>coil system and my spare 25 kVA unit are U.S. made -  Solomon, KS.
>and Laurel, MS., respectively :^))
>David Rieben
>-------------- Original message -------------- 
>From: "Tesla list" <tesla@xxxxxxxxxx> 
>>---------- Forwarded message ---------- 
>>Date: Fri, 6 Jul 2007 17:44:55 EDT 
>>From: FIFTYGUY@xxxxxxx 
>>To: tesla@xxxxxxxxxx 
>>Subject: Re: Vegas pole pigs can't take the heat (fwd) 
>>In a message dated 7/6/07 2:42:26 P.M. Eastern Daylight Time, 
>>tesla@xxxxxxxxxx writes: 
>>>It sounds to me like the said trans- 
>>>formers in Las Vegas may have been a bit underrated to begin with and/ 
>>>or they may have been toward the end of, or even past their useful life 
>>>cycle and the current heat wave may have been the "straw that broke 
>>>the camel's back". Any more qualified comments? 
>>I'd say it's the combined effect of several related causes. The 
>>electrical infrastructure of the USA is still expanding and changing. 
>>Over the past few decades, manufacturing has been declining 
>>(precipitously so in the past decade). These jobs have been replaced by service 
>>industries. Factories and supportive industrial zones were usually located near 
>>shipping routes (highways, rivers, rail lines, ports). But offices and strip 
>>can go anywhere. 
>>People have been buying houses like crazy. Again, a housing development 
>>can be built just about anywhere. Those strip malls and offices go 
>>hand-in-hand with the new housing. 
>>People are also living longer. Perhaps because of better quality 
>>healthcare being more widely available (affordable is another issue!). More 
>>people alive means they need more doctors to *stay* alive. So more doctors, 
>>more lawyers and other service/support industries (offices and strip malls). 
>>they are staying in their houses longer, so there are less houses available 
>>which means more new houses for first-time buyers. 
>>So the geographic distribution of electrical power is getting more and 
>>more spread out, from heavy consumption in urban/industrial centers, to all 
>>over the place - even remote rural areas. So this means *more*, smaller 
>>distribution transformers to all these little loads. 
>>Las Vegas, for example, is a huge electrical load in the middle of the 
>>desert. Even in Arizona, housing developments are taking over desert land 
>>(right, D.C. Cox?). The irrigation and service industries in these areas 
>>decentralize the electrical loading in areas further from the electricity 
>>Existing power generating plants were built near industrial centers. But 
>>we aren't willing to tolerate new nuclear plants, nor does the population 
>>want to live next to a coal-burning power plant. Again, power plants need to be 
>>built near transportation centers to bring in fuel, or at least near a body 
>>of water for cooling (nuclear). If the houses, offices, and strip malls are 
>>being built away from the power plants, more transmission and distribution 
>>equipment is necessary to bring the power to the people. 
>>Fine, except the people *using* these loads have nothing to do with 
>>producing the distribution equipment! Since factories in the US are closing, 
>>pole pigs and distribution equipment is increasingly being made overseas. I 
>>see a lot of ABB brand distribution equipment here in the US, and I would 
>>presume the quality is high. I *do* know Europeans tend to design things with 
>>smallest "service factor" possible, with the least amount of copper (don't 
>>get me started!). And many "American" brands are having their distribution 
>>equipment made in Mexico (don't get me started on *that*!) Either way, the 
>>quality and/or robustness of foreign equipment is often not up to the "old 
>>that many utilities could "count on" to take the abuse. 
>>There's also the side effect of fewer engineers in the USA (because of 
>>less manufacturing and more service jobs), and the shift of engineering duties 
>>to unqualified personnel. So we have people making decisions about the 
>>distribution network who don't have the experience or credentials necessary. 
>>I would *speculate* that many utilities are owned by controlling 
>>interests that have no experience or knowledge about the utilities business, 
>>only treat their utilities according to profit margin, not quality of service. 
>>The materials cost of distribution equipment is sky-high at the moment, 
>>due to the metal commodities used in their manufacture. This puts pressure on 
>>both the manufacturer (to reduce safety margins/service factors by using the 
>>least amount of material to remain competitive in pricing) and on the 
>>engineer to keep project costs down (or the project won't happen, or the job 
>>won't be awarded). So I would suspect increased use of refurbished old 
>>transformers - but will fresh oil cure heat-damaged insulation? Diagnostics to 
>>or identify problems in electrical equipment continues to improve, but it 
>>costs money and skilled personnel (more money). The lead time for distribution 
>>equipment has drastically increased as well. So there's also the result that 
>>more loads are put on existing equipment, instead of properly upgrading it. 
>>I speak from experience in my neck of the woods, that getting a utility 
>>to increase the size of a service because of an increase in load demand is 
>>like pulling teeth. At my last two jobs, we increased the load on old services 
>>significantly, with continuous demand (18+ hours a day/six days a week). The 
>>utility refused to upgrade, and when they did, they ran service conductors 
>>that were half the size they needed to be. It wasn't until we threatened 
>>lawsuits over loss of service/factory production that we got to explain to 
>>engineers the situations and get them corrected. 
>>-Phil LaBudde 
>Date: Fri, 06 Jul 2007 19:18:39 -0400
>From: BRIAN FOLEY <ka1bbg@xxxxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: Re: Vegas pole pigs can't take the heat (fwd)
>Hi, interesting,  originally they were sized for the estimated demand, i bet
>if you measured the wattage they are actually running at peak demand, it
>probably is more than twice rated. in this town we have 3 transformers
>feeding 3 towns from here. the transformers were rated at 200 kva, those
>caught on fire in the winter, were replaced by 450 kva, and this spring one
>burned up so that one is now rated a550 kva and seems to working ok.
>they take a lot of punishment. cul brian f.
>Date: Fri, 6 Jul 2007 15:23:09 -0700 (PDT)
>From: G Hunter <dogbrain_39560@xxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: Re: Vegas pole pigs can't take the heat (fwd)
>This is a puzzle.  I'm no engineer, but I think pole
>transformers are protected from overload by a
>"blowout" fuse or a mechanical recloser.  If too many
>customers switch on the AC, why don't these protect
>the transformer from excessive current?
>I lived on an Air Force base in the deep south for
>many years.  Every year on the first really hot day of
>summer, a large polemount (supported on a trestle
>between two poles) transformer would fail at the
>hottest part of the afternoon.  Even though this pole
>unit was 2 or 3 blocks away, I could hear it fail just
>before my base housing unit lost power.  I recall the
>distinctive growling sound of power arcing so loud it
>echoed around the base.  Once or twice I actually saw
>the flicker of blue-white light playing off nearby
>trees and structures, even in the brassy summer
>sunshine.  Once it actually burst into a smokey,
>spectacular fire, flaming oil dripping to the ground. 
>Fortunately, the errant unit was in an open area away
>from houses and streets.
>This was between 1984-95, and I've forgotten exactly
>how many times it failed, but it happened often enough
>that I came to expect it every year--sort of like the
>4th of July.  After one such summer failure, I noticed
>the replacement unit was much bigger than before.  The
>transformer never failed again.  I guess somebody
>finally got a clue.
>If the smaller, failure-prone unit was overloaded by
>peak summer demand, why didn't the protective devices
>kick in?