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Hi everybody,

Few days ago, I randomly watched this very impressive video: high voltage fire

I'm really surprised by this movie, could someone explain me how that is possible to happen? I think it happened in France.

Thanx in advance for your replies.
 

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Hi everybody,

Few days ago, I randomly watched this very impressive video: high voltage fire


I'm really surprised by this movie, could someone explain me how that is possible to happen? I think it happened in France.

Thanx in advance for your replies.
Good stuff welcome to the forum..:thumbup:
 

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Im guessing the 230/400 volt tap going underground was shorting out, melting itself each time from the shorting all the way to the top of the pole.

The primary obviously was either unfused or overfused.
 

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Either the short wasn't sustained long enough to open any over-current device, or the overload simply caused the OCD to fail in the closed position.

 

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Either the short wasn't sustained long enough to open any over-current device, or the overload simply caused the OCD to fail in the closed position.


In this case, the cause was a broken fuseholder in the substation's control system room that prevented the SCADA system from notifying the operators of the fault. . The failure of a $5 part resulted in the destruction of the entire substation. This was the Ives Dairy substation in Florida. (It later suffered another severe destruction when a stray cat got into some bus work and started multiple fires.) I found the cause of the cat incident on a lineman's forum, and one of the many copies of this video on YouTube had a detailed explanation of this incident in the description posted by one of the POCO worked who repaired the damage.

EDIT: Found the following description of the event from another version of the video, quoted for your enjoyment:

On August 17th 1993, the Ives Dairy Substation in Miami, Florida experienced a total system failure when a power surge on the Miami grid fried one of the capacitor banks, and caused a breaker to trip open. Unfortunately, the breaker malfunctioned and created an arc fault (a continuous lightning bolt that acted like an uncontrollable welding torch from hell) between the hot side of the breaker and wherever it could find a ground to complete the circuit, thus pulling far more current then the facility was designed for.

Unknown to FPL operators at the time, the emergency response system that would have notified the grid dispatcher of a serious problem (who would have then cut the power to the substation and neighborhood to kill the arc fault) was inoperative, and no message was ever sent. Since the dispatcher had no way of knowing about the arc fault, the substation continued to self-destruct.

The uncontrolled arc fault caused the coolant (mineral oil) inside the primary transformer to overheat to critical levels until it was boiling in a highly flammable state. This boiling caused pressure to rise inside the transformer (like a pressure cooker) until the seals finally blew. Mineral oil vapor proceeded to pour out at that point (the plume of white fog at the end) which ignited on the arc fault. The flames caused by this immediately ignited back to the source, (the boiling transformer tank), which ignited the mother load of oil inside causing the substation to explode in a giant ball of fire.

The sudden loss of all transformer coolant resulted in a simultaneous flash-meltdown of the transformers innards, which immediately caused the main high voltage fuse to overload and blow (the loud explosion at the end), finally killing the arc.

As a side note, even though it sounds like a million things went wrong, there were really only two main things that went wrong. Arcing is actually very common when a breaker opens since the breaker has hundreds of thousands of volts running through it. And capacitor bank failures are common since they can fry in the event of a power surge.

The UNCOMMON event that caused this was the fact that the arc-fault suppression system (the system that extinguishes the arc), and the Emergency Response System (that would have told the grid dispatcher that something was STILL wrong) were both placed on the same circuit breaker, and that breaker was faulty. Those two backup systems are really the only final thing a substation has in order to prevent this from happening in your neighborhood, and both of them were inoperative in this instance because of that bad circuit breaker, (and the fact that someone put both the backup system and the auxiliary backup system on the same circuit to begin with - a big no no).

You can view an aerial photo of the substation location here: http://maps.google.com/maps?f=q&hl=en&geocode=&time=&date=&am... (Note: this is a current map photo of the newly rebuilt, slimmed down substation that sits where the old substation used to be.)
 

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The substation fire in the dairy was beside a golf course or park and in the long version of the video many people walk past the fire and some nearly around the time of the explosion. It was a miracle that no one was burned or electrocuted. Worse it shows how little awarness of the danger to passers by. Of course the resultant fire ball was a lot larger than I expected too.
 

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The substation fire in the dairy was beside a golf course or park and in the long version of the video many people walk past the fire and some nearly around the time of the explosion. It was a miracle that no one was burned or electrocuted. Worse it shows how little awarness of the danger to passers by. Of course the resultant fire ball was a lot larger than I expected too.
Got a link to the long version of the video?
 

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Good stuff welcome to the forum..:thumbup:

Bit hard to say for sure but here goes,

Wires running down pole,
Damaged isulation, water and dust accumulte.
Arcing comences, might not throw breakers
if fault current below trip out point.
Falling debrie probably burning ex insulation material.

Anything else.
 

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http://youtu.be/tp1S1YrPYik


Just saw this. Not nearly as impressive but much closer.


I wish I had a camera when some aluminum pots at the smelter I worked at started leaking. That was kind of scary. Almost jumped out the window once.

edit: How do you get youtube to embed?
1: Copy the YouTube link from YouTube
2: When doing a post, click on the
icon
3: Paste the copied link between the [...] and[/...] (Those brackets will have "YOUTUBE" written in them where I put the .... )

It'll end up like this:

 

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Hi everybody,

Few days ago, I randomly watched this very impressive video: high voltage fire

I'm really surprised by this movie, could someone explain me how that is possible to happen? I think it happened in France.

Thanx in advance for your replies.

Bonjour et bienvenu au fourm ici.,

Je n'étais pas trop loin de l'endroit où les dommages causés par le feu de 415 volts défaut d'arc.

Quel est le rôle de la France es-tu en ce moment?

Plus la tension il va le plus l'arc s'affichera.

Il ya beaucoup de vidéos sur youtube leur montrer à quel point il peut être, et juste attendre et voir certains des plus grands transfomer partir en fumée et spectacle de feu assez grand avec grand bruit.


Hello and welcome to the fourm here.,

I was not too far from where the damage by fire caused by 415 volt arc fault.

What part of France are you in now ?

The higher the voltage it goes the bigger the arc will show up.


There is alot of youtube videos show them how bad it can be and just wait and see some of the larger transfomer go up in smoke and pretty big fire show with loud noise.


Merci,
Marc
 
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