Holy ......!!!!!

Thank goodness no one was hurt by all this!!

I'll bet the sound was also very dramatic and scary.

A very sobering reminder of how dangerous electricity can be.

WOW!!!

That sound must've been more than scary, try deafening!!! I can only imagine the force a fault of that magnitude would have! I believe it was iwire (Bob) that once said... "Lest we forget..."

Amen to that and the fact that (hopefully) no one was injured

-Randy

there were...TWELVE... faults before it all ended, I had more pictures, but i can't find them. the whole thing lasted about 30 seconds...and I didn't know whether to wind my butt or scratch my watch....it is terrifying to be only 20' from something like that and not have anywhere to run....
in other words just sheer PANIC , there were about 15 people standing in the area

this is sounds as bad as when our bus duct blew up at work. needless to say it only last a few seconds but it shut the entire plant down for two days.i belive it was a 1200 amp duct at 480 volts.it caused the breakers to trip in the substation about 4 miles down the road. not only scaring us to death , but having some pretty upset residental customers down the road. come to find out that some one had paralled all the busses to all three pad mounts in the back yard which amounted to about 3600 amps+i think a few of us had to change our shorts, not to mention hide some where when they asked who had done the switch gear. luckily no one was hurt. just scared!

[This message has been edited by circuit man (edited 10-02-2005).]

......yeah, know what you mean, The cables that come up in the bottom of that cabinet were a temp feed (4160 ) from a tranny in back of the building... which had NO relay protecton on the secondary, needless to say , when the fireworks quit, the engineers ran over to the cabinet and OPENED the door,
The Lineman foreman was on the radio SCREAMING that the transformer was still LIVE and to stay away from the cabinet, two of the cables were still HOT..
those engineers were very lucky that day.
as I said, I have more pics and I hope I find them, in those, are pictures of the engineers opening that door

......

togol:

Twelve faults?! Double wow.

I've been trying to figure out from the first pic what was in flames..was that the transformer, the "MPT" (For us unfamiliar, what's that?), or a different angle of the cabinet?

And with so many people around, very lucky indeed that no one was hurt.

Was this a result of miscommunication or are you not at liberty to discuss that?


edietd to remove irrevelant question

[This message has been edited by mxslick (edited 10-04-2005).]

..sorry , MPT.. main power transformer,
in the second shot there is a scorch mark on the wall ,see it ? from where I was hiding I was looking straight toward that mark, or perpindicular to the sidewall.

the generators 138Kv output supplied ...thru an Aux. transformer in the middle of the first picture... plant power ..(4160V ) and then the MPT whose HV side was 345Kv
I was in the area , along with about 15 other folks, waiting for a test of the MPT to begin, ( it had been taken out of service because of a very bad installation procedure that had damaged the 138Kv bushings.... ) prior to the repairs, and following a procedure the cables from the Aux trans. were disconnected at the terminals in the damaged cabinet and
the temporary power was then reconnected to those terminals and a barrier was placed in between the live and disconnected cables. additionally the utilities Air break and the Air break at the MPT were locked OPEN.

This plant was still in the comissioning stages and not fully operational,and the clock was running
when the repairs were completed about two weeks later, the start -up folks wanted to get under way ASAP !

Now ,I was the GF for the start -up crews and was out there to basically CYA if there was a problem. in other words ..just observing
I was standing next to the senior start-up engineer when the test began, it occured to me that no one had insulated the still disconnected 4160V cables in the top of the cabinet, and I mentioned that to the Eng.......
.......this space left intentionally blank......

I also had my camera w/ motor drive with me , and started snapping away when the Air break started coming closed......

its been 4 years and I can still hear that sound, ...look in the back of the truck, see the red GAS tank

Is this a peaker or some kind of co-gen facility?

How could such serious errors go by unnoticed?

Well, I guess as the saying goes, "It's only money!"

Peter

CT, its a peaker in Aurora Il.
it wasn't unnoticed, ....it was ignored !!!

togol

How I envy you.

I never have great stories to tell.

The best I can do is recount some semi-suicidal apprentice boner; and none of them would be news to anyone.

I am pleased no one was hurt.

It seems that some sort of LOTO breakdown occured.

togol:

Thank you for the clarification. So if I read it correctly the fireball was coming from the damaged cabinet....

I would have probably changed careers after such an event, since I've seen and heard many incidents which make me very cautious around any electrical gear. To still have such vivid memories after four years...

Truly a miracle no one was hurt, indeed. But I imagine that like you, they still have effects from that day.

A bit OT here:
BTW, in the thread "what do you look like?" was that switch in the pic at the same facility? I'll bet the "bark" from the "B" phase was a pucker-inducer as well.

Here's the link:
https://www.electrical-contractor.net/ubb/Forum1/HTML/002850-7.html

My very first exposure to that kind of horrible sound was when as a kid, I was bicycling past a pole with a transformer when it got hit by lightning. The concussion knocked me clean off my bike and the arc's noise gave me nightmares for months. But it did later reinforce my interest in all things electrical.

Edited to add link for your viewing pleasure...

[This message has been edited by mxslick (edited 10-08-2005).]

Tesla,
it WAS a once in a lifetime event ,that's for sure.....

.. a bit more explanation, that damaged building is where ALL of the LOTO for the plant power is done,in other words , the tranformers 4160V output can be isolated in that building, but the 138Kv feeds for it are either from the generator ,or a backfeed from the utlity thru the MPT.


normally, opening the gen. breaker and the airswitch isloates the primary and a breaker in the building isolates the secondary

Tom

[This message has been edited by togol (edited 10-07-2005).]

mxslick, yes that is the same job, taken in Spring that year, ironically, I had to get a butt chewin' ....by the SAME engineer who was running the test that led to the fire.....,
about damaging the switch in my photo

Sounds to me like that "engineer" is the one in need of a serious butt chewing, at least. After this incident that chap would never work on any project I owned for sure.

Chews you out for opening a switch? Bet ya the "fault" on "B" phase was due to him in one way or another.......

See more pics Here



[This message has been edited by electure (edited 10-22-2005).]

Togol, thanks for sharing your experiences with this. I work in a power plant and frequently do the switching in the high voltage rack and appreciate how very lucky everyone is to walk away from this one. I have seen a few failures, but thankfully nothing of this magnitude, and nothing caused by faulty procedure. Someone must have had to clean out their pants after this one.

One point though, are you missing a decimal point in your voltages? Our generators put out 13.8 Kv, and our primary switchrack uses 34.5 Kv. At first I thought you must have been working with a really large unit, but the numbers just make more sense to me with the decimals.

CaOperator, at that job everyone involved always referred to the outputs those two units as "345".... while the others were
"138 " , the MV was called thirteen eight, or 13.8 .
It was, as I recall, a really big deal on the morning that the big line was energized ! The start-up folks wanted EVERYONE to stay in tthe trailers while they brought that it up. Something that wuold not occur with energzing 34.5 Kv

The short answer is that the line was 345Kv. .......I couldn't beleve it either, as it was my first exposure to REALLY high voltage

This plant was plagued with many mis-haps , another ...near-miss...involved that same line, near the end of the construction phase.

After some initial checks ....
The Utility opened their switch in their yard and ..following their safety procedure...,pulled a pin out of the mechanical linkage..to prevent an accidental closure.

On our side, they followed LOTO, plus, a thoughtful lineman installed some 4/0 "safety grounds" on the high side of the transformer , at the switch !

Naturally, we experienced some VERY high winds a few days later, which, because of the missing pin, .... and unknown to anyone inside the plant ....,caused the Utility switch to fall closed .
energizing the line, but because of the wind , no one could hear it !

Our switch , which was under LOTO in the control room, started to drift closed, until it finally got close enough to those grounded stabs and then BLEW the 4/0 grounds clear which caused a TRIP on the Utility side....
There were men working on the other side of the transformer blast wall when this happened, and while no one was physically injured , there were very many ummm, pissed -off electricians

BTW, the lineman got his butt chewed out for hanging those 4/0 grounds on his own initiative, but his actions prevented a very, very serious catastrophe.
as usual , the lineman boss forgot to apologize to the guy afterward

togol

DRIFTED CLOSED????!!?? I (and several others, lol)would have somebodies butt for that one. What good is a self closing air gap? Our switchrack disconnects ALL have padlocks on them, both in the open and closed positions, if they changed positions accidentally then there has been a serious failure.
And hanging grounds requires everyone involved to be notified.
It sounds like there were two seperate work authorities issued here and there was no proper written procedures. Even in cases (or perhaps especially) of abnormal conditions we take the time write up a procedure and review it with all parties.
I am thankful the agency I work for does not engage in russian roulette switching like that.
Again thank goodness you and all others are safe and whole.

Bump...
Or if you prefer, tapa, tapa....