Written pole motors

[Dean Hoffman]

This U.S. company says they can make larger single phase motors up
to 75 horsepower. I was wondering about the good and bad points of
this. http://tinyurl.com/24c92bs

Thanks.

 

[Guest]

Looks ALL GOOD to me.



You are welcome.

IF claims are as stated.
How does the stator adapt to the necessary conditions without some sort of
feedback control? It appears to be a variation of previously existing PM
motor technology.
It may be very good but, surely, on the basis of the reference- there is no
more than PR handwaving.

 

[daestrom]

IF claims are as stated.
How does the stator adapt to the necessary conditions without some sort
of feedback control? It appears to be a variation of previously
existing PM motor technology.
It may be very good but, surely, on the basis of the reference- there is
no more than PR handwaving.

Just looking at the numbers in the table under 'Benefits of Technology'
(page 3), there are some discrepancies. For the conventional 3-phase
motor, the power doesn't work out right for a 0.85 power factor. Nor
does the stated kVA.

If the technology's valid, I can see a niche market were you need a
low-starting current motor. But it seems like the added complexity
would result in a higher price for 'average installations'.

daestrom

 

[James Sweet]

I "explored" the company's website.

There was an interesting instalation up in Wisconsin or Michigan in an
irrigation application.

The farmer worked with the power company to help select the motor. The
power company knew it couldn't give the farmer 3 phase power nor could it
tolerate excessive start up currents.

On the surface this sounds a lot like the old repulsion-induction
motors. Wasn't low starting current one of the big advantages of those?

 

[Charles Perry]

This U.S. company says they can make larger single phase motors up to
75 horsepower. I was wondering about the good and bad points of this.
http://tinyurl.com/24c92bs

Thanks.

I have been involved in testing some of these as well as applying them in
the field. They do work. The downside? More expensive, more complicated.

Charles Perry P.E.

 

[Dean Hoffman]

I have been involved in testing some of these as well as applying them in
the field. They do work. The downside? More expensive, more complicated.

Charles Perry P.E.

Can one make any educated guesses about durability? I was
thinking of the irrigation application mentioned by John Gilmer.
Irrigation well motors generally sit outside. They are usually in the
50 to 75 hp. range in my area. They get hit by blowing dirt, crop
dust, precipitation, and whatever else the wind can carry. Lightning,
and air temperatures ranging from about -20ºF to over 100ºF are part of
the deal.

Thanks

Dean

 

[Charles Perry]

Can one make any educated guesses about durability? I was
thinking of the irrigation application mentioned by John Gilmer.
Irrigation well motors generally sit outside. They are usually in the
50 to 75 hp. range in my area. They get hit by blowing dirt, crop
dust, precipitation, and whatever else the wind can carry. Lightning,
and air temperatures ranging from about -20ºF to over 100ºF are part of
the deal.

Thanks

Dean

I know of units that have been in the field for over 10 years. I have not
heard of any reliability issues.

Charles Perry P.E.