Does anyone have any detailed or first-hand info about the power outtage at the Bellagio Hotel? Where, exactly, was the damage and what caused it? Was it arcing or tracking inside of a high-voltage transformer? What was the voltage, 4160? 12KV? If you have any details, please post here. Thank you.
-Gary Sanders
A couple of artices with no techncal content are
Minor local coverage...
--s falke
What I heard: Someone had just tested the cables from their central plant into the hotel and then the failure occurred. Seems they have dual feeds plus their generation to the central plant. But only one set of cables to the hotel. OOPs I believe the cables were 15k.
I can ask again next month when I go to the power quality meeting.
Here is the back-room story from someone in the know.
They have (had?) a 2000A 15kV main switch from the utility that had a cable feed to a bank of 100A distribution switches. Each distribution switch fed a substation for various load zones. Each load zone had a
12.47kV geneset tapped in with a "T" connection to the primary of each sub.The original fault was in one cable from the 2000A main to the distribution switch bank main bus. It was a low level insulation fault that apparently arced and smoldered for some time before being cleared.
The major catastrophy was that in an effort that saved $2million in cable costs by going with 12.47kV gensets and T connections, they unfortunately stuffed all of these 15kV cables into the same duct bank, along with that feeder that failed, and of course it was on the bottom of the duct so the damage spread upwards. So the relatively simple failure of that one cable took out not only the entire distribution system but also all of the backup systems as well!
The rumored total is that the outage has cost them $20 million so far.
You didn't hear it from me though ;-p
Awesome... Thank you. That's exactly the type of answer I was looking for, but didn't hear from you. ;)
Gary
But it WAS a Y2K problem. Had not all that fuss been made about Y2K and the (false) claim that it was the start of a new milenium, that balloon would not have been inflated!
Actually, the only catostrophic breaker failure that I ever saw was caused by a common house cat. It was a three phase 15kV breaker and the cat shorted between the source bushings and line bushings. The fireball kept the short going long enough for the breaker to self destruct. Amazingly, there was enough "cat" left to identify it as such.
Snakes are even more problematic. They can "reach" quite a bit farther than a cat to short out even higher voltage buses.
Animals cause many, many, many outages. Believe me, I analyze tons of outage data every year for utlities. It is amazing how much improvement in reliability can be achieved by simply installing animal guards on primary equipment.
Charles Perry P.E.
ISTR reading that the distance between the insulators on a
11kV line was determined by the average length of a domestic cat when the tail was held out - apparently it was a form of entertainment when electrification of districts first came along.
Hahahaha. That is at least a good story. Look at armless construction and you will see that a cats tail alone could short across. Also, spacing in stations is usually much less than that on lines.
Charles Perry P.E.
It figures. Next thing you know, the industry will define a "standard cat".
In some areas, the spacing on crossarm construction isn't sufficient to allow an eagle to spread its wings to take off from the crossarm. Since the poles tend to be the best (only) good vantage point for birds looking for prey in fields, a number of them got killed until the local utilities put up T-shaped perches above the crossarms.
How did we get from the Bellagio electrical outtage to crispy kitties and snookered snakes? Funny how these topics tend to drift. :)
-Gary
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