Posted on 11/09/2012 6:51:48 PM PST by zeestephen
If a new engine "commutator" has to be built by General Electric, the Walla Walla could be out of service for up to two years. An electrical surge caused huge chunks of steel and copper to melt, as well as holes to be blasted through the six foot diameter engine part.
(Excerpt) Read more at msnbc.msn.com ...
Dang it! I hate it when that happens....
Rode the Walla Walla many, many times.
Oh, Susannah...it’s a MOTOR that failed, NOT an ENGINE! But you’re a dame, what would you know?
Sounds like they put full power to one of the motors with its rotor locked. Sounds like it was in that situation for more than a few seconds.
Maybe if you gave her equal pay FOR THE EXACT SAME WORK she would do a better job!
/sarc
The same Washington State that voted for same sex marriage-gee, what a surprise.
The Washington State Ferries are near perfect example of state controlled industry. It is like the Soviet Union is running the system.
These 70 year old tubs are rusty buckets.
The whole fleet should be sunk and used as an artificial reef for the benefit of sea life and fisheries.
The state bans private companies from offering competition, thus insuring union workers job security.
Seems like they would have noticed the lights dimming with all of that current shorting out.
Once you let the magical smoke out of electrical devices, they never work again. (^;
Indeed. And one who scrawls for MSNBC.
Get me a beer, woman, and wash my shorts.
“And look for the union label....”
You might be interested to know that the article does NOT refer to it as an engine, but the summary does. Perhaps they cleaned up their own mess.
Sorry, the “engine” goof is mine.
I cut and pasted some sentences.
I think “engine” came from “engine room.”
I wonder if he was one of them that moved up from San Francisco.
Yeah, that occurred to me too. But they may have been using shore power. If they test those motors under full load as part of the qualification procedure, those mains could have sourced many megawatts steady-state without too much complaint.
Looking at the pictures, it's obvious that the rotor was locked. One set of commutator bars is completely melted. Adjacent bars are coated with flash products but not themselves melted. Quite a lot of copper — by which I mean pounds of it— appears to have been vaporized.
The only other possibility I can think of (and this goes beyond my knowledge of large motors) is that perhaps they somehow managed to energize forward and reversing circuitry at the same time. I say that because it looks like the current actually travelled laterally, from end to end, the long way, through the commutator bars. All the brush holders are smoked, and the carbon brushes appear to have burned away. Perhaps half the brushes are used for forward and half for reverse... that seems a bit old fashioned, but who knows how old these propulsion plants are. They mentioned "boilers" in one of the stories, which indicates they're kind of long in the tooth.
If they had actually put full voltage to the motor with the rotor locked, one would expect that the rotor windings corresponding to the energized commutator bars would also be melted, or at least have been heated to red hot. That would have severely damaged the rotor itself and the adjacent windings. No such damage is shown in the pictures or mentioned by the story's "sources." In that case, I would thin we'd be looking at a lot more than a commutator rebuild.
Once you let the magical smoke out of electrical devices, they never work again. (^;
Yup. Putting new smoke back into a motor with a six-foot diameter commutator would cost some real money, I'm guessing.
Sounds like a “smoke test” gone bad.
No private company would provide WSF service levels.
Not that I would advocate anyone deliberately doing anything like this of course...
It seems like they would just reverse polarity to reverse rotation.
I think you are correct, the commutator was locked and they forgot that fact when they went back online.
I have never worked with motors anywhere near that size bit did get to see the results years ago of what happens when you bring a hydroelectric generator online extremely out of phase with the grid.
Buddy of mine bought a new truck with some of the overtime he got.
Ah HA! Apologies to Susannah. Stephen, put down the Barbie Dolls and go pick up an oily wrench!
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