"Tesla Motor", ever hear of it? 1

[jraef]

I'm going out to a mine in Arizona tomorrow to discuss a couple of projects we are working on, and yesterday one of our salesmen told me that at this mine, they have a very old motor that he referred to as a "Tesla Motor", apparently built by old man Nick hisself. He said he was told it is one of only 4 ever made and 2 in existence, and when they take it out of service it is already promised to the Smithsonian. They have the other remaining one but it is not working, this one is apparently still in use at the mine. I doubted the veracity of this but in checking, the mine is actually old enough to have been around when Tesla was making motors (pre-Westinghouse), and he did come out to Colorado Springs, which is not all that far away. But I could find nothing with my favorite search engines on what this motor might be.

This was couched in a discussion of applying VFDs to wound rotor motors on ball mills, and the salesman described this as "the weirdest soft starter he has ever seen". As it was described to me (by a salesman mind you), the motor starts up and BOTH the rotor AND THE STATOR rotate (I know, an oxymoron right there). Then when they want to have it take on the full load, they apply a mechanical brake to the "stator" part and slowly bring it to a stop, which then allows the rotor to slowly take on the full loading. The concept kind of makes sense to me actually, but I am now in full curiosity mode and I'm hoping that I can convince someone at the mine tomorrow to let me take a peek at it and maybe even snap a few pictures , or joy of joys, a brief video!

I find nothing on it with relation to Tesla, and unfortunately now when you say "Tesla" and "motor" in a search engine, you get a bazillion hits on Tesla Motors, the car company, clogging up the results. I looked at the Tesla Electric Motor on display in the Smithsonian website, but it is one of his original prototype 2-phase electric motors and fairly small, nothing that would have been all that useful in a copper mine at the turn of the century.

Anyone else ever heard rumor or story of such a thing?

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> faq731-376

 

[MikeHalloran]

ISTR, maybe 40 years ago, a flurry of publicity, and maybe even a patent, for a large motor that started with the 'stator' rotating, and braked it to accelerate the rotor and the load.

I don't recall Tesla's name being associated with it, other than inventing the progenitor of all polyphase motors.

Somehow I associate the borough of Brooklyn, NY with it.

It predated the availability of large cheap VFD drives, which surely killed any market for it.




Mike Halloran
Pembroke Pines, FL, USA

 

[MikeHalloran]

Here's a page with comparative anatomy of Tesla's motor patents, some of which may be useful:

http://twinkle_toes_engineering.home.comcast.net/~twinkle_toes_engineering/induction_motor.htm

Mike Halloran
Pembroke Pines, FL, USA

 

[waross]

A couple of brain cells fired at the mention of braking the stator to accelerate the load. I'll have to think on that for awhile. It may have been mentioned in an old text book that may have been lost in my three way moves between British Columbia, Honduras and Alberta.
I'm looking forward to hearing more about this one.
Thanks for sharing Jeff.
Yours
Bill

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Zogzog]

I would love to see this thing, pleas eget photos (This isn't in Kingman by chance is it?).

Some guy brought in a small Tesla motor on Pawn Stars, turned out it was made by Tesla for classroom use as a demo to get kids interested in electricity, that was pretty cool.

High Tops
Premiere Date: 12/26/2011
The Pawn Stars feel a jolt of history when a guy brings in the original AC motor built by Nikola Tesla. Considered one of the most important inventions of the 19th century, will they power up a high voltage deal for this national treasure, or will the negotiation run out of juice? Don't get me started with Tesla motors, I am mad at them.

 

[jraef]

No it's not Kingman, but I was there and that's where the conversation took place. It's apparently at the Freeport McMoRan Miami mine. Going to be there this afternoon.

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> faq731-376

 

[jraef]

Damn. The meeting was cancelled. And it was the Freeport McMoRan Morenci mine, not the Miami mine. Oh well, gives me something to look forward to for the next trip in a couple of months.

But one of the specialists says he has a photo he will email to me tonight, I'll post it if i get it.

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> faq731-376

 

[Zogzog]

Great steaks at the Dam Bar in Kingman, and some good local brews on tap too.

 

[jraef]

Had a Dam steak at the DamBar! Had the Dam Fries and the Dam Salad withe Dam Special Dressing too...

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> faq731-376

 

[OperaHouse]

That reminds me of going to a steel mill in Lakawana. They had a large GE pit motor they were wanting to replace. You know, they sold you the rotor & stator and you made the rest out of concrete. They had no idea of the HP. It looked like Edison himself had wound it. We quoted 3 hours to do the telemetry and got there at noon. Left 3 days later because they would only shut it down 5 minutes at a time and then only when something on the line broke. It drove a rolling mill in the next bay with this shaft that was bent up like a cork screw. It would just flop in the floor as it spun. By the end of the steel bar the motor was about grinding to a hault.