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Explosion on Bridge Caused by 'Thermic Event:' Police
NBC10 ^ | Feb 1, 2013 | Lauren DiSanto

Posted on 02/01/2013 7:21:28 PM PST by fatima

Four people were hospitalized with minor injuries Friday night after an explosion on a bridge over the train tracks at 30th and Cecil B. Moore in Brewerytown.

The explosion was originally thought to have been an explosive device, but after an extensive investigation, police are calling it a "thermic event."

(Excerpt) Read more at nbcphiladelphia.com ...


TOPICS: Culture/Society; Extended News; US: Pennsylvania
KEYWORDS: bridge; explosion; thermic; thermicevent
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1 posted on 02/01/2013 7:21:33 PM PST by fatima
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To: fatima

17,000 volts AC at 16 hertz can cause a lot of damage if bridged by frozen water. I wouldn’t want to be nearby.


2 posted on 02/01/2013 7:24:49 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: fatima

What’s a “thermic event,” an explosion set off by Muslims?


3 posted on 02/01/2013 7:25:47 PM PST by madprof98
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To: Publius

16 Hz?


4 posted on 02/01/2013 7:28:30 PM PST by null and void (Gun confiscation enables tyranny. Don't enable Tyranny)
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To: fatima

Gerbils Swarming?


5 posted on 02/01/2013 7:28:42 PM PST by rfp1234 (Arguing with a liberal is like playing chess with a pigeon.)
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To: madprof98
What’s a “thermic event,” an explosion set off by Muslims?

No, it was set off by Therms. Gee, try to keep up.

Off with there heads!Thermahu akbar!

6 posted on 02/01/2013 7:30:40 PM PST by Graybeard58 (_.. ._. .. _. _._ __ ___ ._. . ___ ..._ ._ ._.. _ .. _. .)
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To: null and void

Depending on where you are, the frequency on the Northeast Corridor can run from 16 to 60 hertz. It has to do with who electrified that stretch of track originally. Thanks to the modern art of thyristors, today’s electric locomotives can change on the fly.


7 posted on 02/01/2013 7:30:49 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: null and void

Yeah, it Hz a lot!


8 posted on 02/01/2013 7:31:25 PM PST by Oberon (Big Brutha Be Watchin'.)
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To: Publius

Crazy stuff,my daughter takes this train everyday.
“Chief Sullivan says icicles formed as a result of the recent moisture and these icicles came in contact with high power lines from AMTRAk that run underneath the bridge.”


9 posted on 02/01/2013 7:32:23 PM PST by fatima (Free Hugs Today :))
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To: Graybeard58
Off with there heads!

What a idiot I is. Their heads not there heads.

10 posted on 02/01/2013 7:32:42 PM PST by Graybeard58 (_.. ._. .. _. _._ __ ___ ._. . ___ ..._ ._ ._.. _ .. _. .)
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To: fatima

Global Warming: It makes bridges explode.


11 posted on 02/01/2013 7:33:08 PM PST by ClearCase_guy (Nothing will change until after the war.)
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To: fatima

Was Al Gore seen lurking in the neighborhood?


12 posted on 02/01/2013 7:33:15 PM PST by Jim Robinson (Resistance to tyrants is obedience to God!!)
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To: fatima

13 posted on 02/01/2013 7:34:06 PM PST by Charles Martel (Endeavor to persevere...)
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To: fatima

Back in the Sixties, I commuted on these lines when I was in college.


14 posted on 02/01/2013 7:34:18 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: Jim Robinson

He’s too big to lurk.


15 posted on 02/01/2013 7:34:18 PM PST by fatima (Free Hugs Today :))
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To: Jim Robinson

Now we know what happens when his chakra is released....


16 posted on 02/01/2013 7:37:19 PM PST by Norm Lenhart
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To: Graybeard58

We got it anyway.


17 posted on 02/01/2013 7:38:53 PM PST by x1stcav (Man up! We're all going to have to become Samuel Whittemores.)
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To: fatima

Why can’t they simply call it a short circuit caused by icicles touching the third rail?

“Thermic Event”, huh?


18 posted on 02/01/2013 7:39:39 PM PST by BwanaNdege ("To learn who rules over you simply find out who you are not allowed to criticize"- Voltaire)
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To: BwanaNdege

Not third rail. Overhead caternary.


19 posted on 02/01/2013 7:41:44 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: fatima

Good thing this never happened back before glogal warming.


20 posted on 02/01/2013 7:43:47 PM PST by REDWOOD99 ("Everyone should pay taxes. Everyone should pay the same rate.)
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To: null and void; Publius

16 , 17 Hz. Whatever it takes.


21 posted on 02/01/2013 7:46:25 PM PST by UCANSEE2 (What difference does it make (if they eat cake)?)
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To: UCANSEE2

16, 17 Hz. What Difference Does It Make????


22 posted on 02/01/2013 7:53:37 PM PST by batterycommander (a little more rubble, a lot less trouble)
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To: fatima

A “thermic event”

Must have been written by the same government weenie who brought us:
“overseas contingency operations”
“kinetic actions”
“affordable health care”
“man-caused disaster”


23 posted on 02/01/2013 7:54:14 PM PST by ProtectOurFreedom
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To: Publius

DC I understand. 50/60 Hz I understand. 400 Hz I understand.

I don’t “get” 16 Hz. I even think the 25 Hz used in some parts of the world is too low. Visual flicker on the lights, unnecessarily large transformers, etc.

16 Hz? Why would they do that???


24 posted on 02/01/2013 8:11:23 PM PST by null and void (Gun confiscation enables tyranny. Don't enable Tyranny)
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To: null and void

You would need to talk to the guys who electrified that stretch of the Pennsylvania Railroad’s Northeast Corridor in 1933. It made sense to the electrical engineers of the time. It probably doesn’t now.


25 posted on 02/01/2013 8:15:12 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: null and void
Visual flicker on the lights

Disco all the time.

26 posted on 02/01/2013 8:17:39 PM PST by The Cajun (Sarah Palin, Mark Levin......Nuff said.)
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To: null and void

Sounds like some old motor generator set that’s older than dirt, and maybe older trains needed (need?) the low frequency to run special slow synchronous motors. Just a guess... today, if trains can deal with multiple frequencies, it would of course make sense to tie it directly into the utility with transformers and have it be 60 Hz.


27 posted on 02/01/2013 8:18:41 PM PST by HiTech RedNeck (How long before all this "fairness" kills everybody, even the poor it was supposed to help???)
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To: Publius

They probably wiring in heaven now... I would guess it was a need of synchronous motors on the trains of the time. The capability of rectifying the currents required to move a train had to wait for the era of silicon semiconductors.


28 posted on 02/01/2013 8:22:47 PM PST by HiTech RedNeck (How long before all this "fairness" kills everybody, even the poor it was supposed to help???)
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To: The Cajun
Visual flicker on the lights
Disco all the time.

Heck of a thing for epileptics

29 posted on 02/01/2013 8:28:44 PM PST by HangnJudge
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To: HiTech RedNeck

Correct, I’m sure. In the old days, there was a locomotive change at the Pennsylvania Station in New York, and not just because the New Haven took over from the Pennsy. The New Haven’s 1906 electrification was set to a different frequency.


30 posted on 02/01/2013 8:28:55 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: Publius

Sorry, my misinterpretation of the story. I figured that below the roadway meant 3rd rail.

I was thinking of the old DC trolleys when I was a kid. Underground 3rd rail in town, but they did go to overhead catenary once out of the built up areas, like the run to Glen Echo.


31 posted on 02/01/2013 8:32:02 PM PST by BwanaNdege ("To learn who rules over you simply find out who you are not allowed to criticize"- Voltaire)
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To: fatima
Obviously warming up for the next Spidey movie.


32 posted on 02/01/2013 8:34:34 PM PST by Bratch
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To: BwanaNdege

When the DC system was built in the late 19th Century, Congress mandated that the trol;eys use third rail within an underground conduit within the District. They went to caternary wire outside the District.


33 posted on 02/01/2013 8:35:51 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: Publius

The former Pennsylvania Railroad section of the Northeast Corridor is electrified with 11,000 volt 25 Hz, as are the former Reading commuter lines. I need to check the historical basis for the lower frequency. Apparently it was a combination of transmission losses, and being able to operate “universl motors” that could operate on DC.
The 17 Hz is actually 16 2/3 Hz of the Deutsche Bahn (1/3 of 50 Hz).
Those are old legacy systems


34 posted on 02/01/2013 8:42:26 PM PST by Fred Hayek (The Democratic Party is the operational wing of CPUSA.)
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To: Fred Hayek
Thank you.

In 1997, I read Michael Bezilla's The Electrification of the Pennsylvania Railroad, and now it's out of print. I was going from a failing memory.

35 posted on 02/01/2013 8:45:19 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: Publius

The old New Haven was also at 25 Hz. There used to be a locomotive change at Manhattan Transfer (not far from the current PATH Harrison station), however, the original Pennsy New York electrification was third rail (600 vdc) from Sunnyside Yard to Manhattan Transfer in order to enable tunnel operation under the Hudson and East Rivers. When the PRR extended the 11kV catenary from Trenton to New York, Manhattan Transfer was eventually done away with.
Now the former New Haven line is 12.5kV 60 Hz to New Haven (formerly 11kV 25 Hz, the old NH power system was badly worn), with the new Amtrak electrification from New Haven to Boston at 25kV 60Hz.


36 posted on 02/01/2013 8:50:49 PM PST by Fred Hayek (The Democratic Party is the operational wing of CPUSA.)
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To: Publius

Thanks!

Great info.


37 posted on 02/01/2013 8:51:31 PM PST by BwanaNdege ("To learn who rules over you simply find out who you are not allowed to criticize"- Voltaire)
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To: Fred Hayek

Thanks for bringing me up to speed. I was drawing a blank on the 1999 Amtrak electrification to Boston.


38 posted on 02/01/2013 8:53:35 PM PST by Publius ("A centralized government is a centralized evil." -- Gen. John Graham)
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To: HiTech RedNeck; null and void; Publius
I wasn't aware the 16 Hz low frequency was used in the US -- it was common in Europe. I thought the standard US low frequency was 25 Hz. Learn something new every day.

Anyway, the history I learned was that a most trains had standardized on large DC commutator motors, which could also be used in AC. Problem was, the higher the frequency, the more internal inductance problems you had. 25 Hz was a good compromise between internal inductive loss and transmission loss on the line.

39 posted on 02/01/2013 8:54:02 PM PST by FredZarguna (Father of our Country Facepalm.)
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To: Graybeard58

They are a radical group called ‘Hz-bull-duh ‘!
A radical group of electrons , inconvienced , and doing self-immolation.

Thermahu Akbar !


40 posted on 02/01/2013 8:54:57 PM PST by Tilted Irish Kilt (" Our enemies no longer fear us, our friends no longer trust us " .. Why would they ?)
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To: Fred Hayek

Yeah that’s mostly my understanding (see previous post.) With AC you could mitigate the huge transmission loss you get with direct current, but as you increased the frequency you start to have higher and higher inductance losses in the windings of a DC motor. 60 Hz was too high for those motors. 25 Hz was a trade-off point between internal losses and line losses.


41 posted on 02/01/2013 8:57:34 PM PST by FredZarguna (Father of our Country Facepalm.)
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To: FredZarguna; Fred Hayek

Thank you gentlemen.

I assumed that there would be a FReeper who actually knew the answer.

Two is an unexpected bonus.


42 posted on 02/01/2013 9:16:23 PM PST by null and void (Gun confiscation enables tyranny. Don't enable Tyranny)
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To: fatima

Oh Dear ! All this thermic stuff beats the Hertz out of me.


43 posted on 02/01/2013 9:27:27 PM PST by mosesdapoet (.Couldn't help it it was too good a catenery to pass up)
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To: Publius

“17,000 volts AC at 16 hertz can cause a lot of damage if bridged by frozen water. I wouldn’t want to be nearby.”

Amtrak catenary on the New York to Washington segment is energized at 11,000 volts 25hz.

Going under an overhead bridge, there’s not a great distance between the bridge structure and the wire itself — the insulators are often short there to maximize clearances between the wire and the rails. What happens is that water which under warmer conditions might drip bridge-to-wire freezes and then extends downward until it may touch the wires, then — zap!


44 posted on 02/01/2013 9:28:01 PM PST by Road Glide
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To: Graybeard58

You gave me a good laugh with that one.


45 posted on 02/01/2013 10:02:45 PM PST by gunsequalfreedom (Conservative is not a label of convenience. It is a guide to your actions.)
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To: fatima

25Hz power came from the design RPM of the Westinghouse Niagra Falls turbines, which were designed before alternating current became the standard. They could not change the hydraulics, so they had to chose between 16-2/3, 25, and 50Hz. 16-2/3 caused flicker, and 50 didn’t work for the motors of the day, so they settled on 25.


46 posted on 02/01/2013 10:20:33 PM PST by Born to Conserve
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To: Publius

To #19. Overhead caternary?

Well, put up chicken wire to keep them darn cats and canaries off the electrical wires.

By the way, he you entered that word in the New Dictionary of corrupted American words?


47 posted on 02/01/2013 10:46:55 PM PST by MadMax, the Grinning Reaper
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To: Graybeard58

Icce therms!

Ugh, make that icky therms!


48 posted on 02/02/2013 1:47:18 AM PST by ApplegateRanch (Love me, love my guns!©)
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To: fatima

Thermic Event = Massive Tig welder.


49 posted on 02/02/2013 3:29:24 AM PST by Candor7 (Obama fascism article:(http://www.americanthinker.com/2009/05/barack_obama_the_quintessentia_1.html))
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To: Jim Robinson
Was Al Gore seen lurking in the neighborhood?

Probably not. There was no report of a seismic event at the same time.

50 posted on 02/02/2013 3:35:44 AM PST by Fresh Wind (The last remnants of the Old Republic have been swept away.)
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