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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
that!
Take care,
Bart
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
>>malls
>>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
>>older
>>people alive means they need more doctors to *stay* alive. So more doctors,
>>more lawyers and other service/support industries (offices and strip malls).
>>And
>>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
>>further
>>decentralize the electrical loading in areas further from the electricity
>>production.
>>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,
>>the
>>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
>>the
>>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
>>stuff"
>>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,
>>and
>>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
>>bid
>>won't be awarded). So I would suspect increased use of refurbished old
>>transformers - but will fresh oil cure heat-damaged insulation? Diagnostics to
>>test
>>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
>>*real*
>>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?
>
>Cheers,
>
>Greg
>
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