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#31745 - 12/02/03 11:56 PM 10 hp Motor  
Keny  Offline
Junior Member
Joined: Dec 2003
Posts: 5
Toronto, Ontario, Canad
10 hp motor in the plant, you heard hum and load noise. What is the problem of the motor?
A. Open field shunt.
B. Phase to phase short.
C. Stator is shorted or went to ground.
D. Something else.....


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#31746 - 12/03/03 12:33 AM Re: 10 hp Motor  
crash  Offline
Member
Joined: Oct 2003
Posts: 147
Calgary Canada
Keny: I like multiple choice exams!

A- Open shunt field. Motor would not run.
B- Phase to phase short. OCP would trip.
C- Stator is shorted or... OCP would trip.
D- Something else....

I think the answer is D.


#31747 - 12/03/03 01:04 AM Re: 10 hp Motor  
jlhmaint  Offline
Member
Joined: May 2002
Posts: 202
Fredericktown, OH, U.S.A
I would agree something else possilbly bearing failure.


#31748 - 12/03/03 08:43 PM Re: 10 hp Motor  
mvpmaintman  Offline
Member
Joined: Sep 2003
Posts: 123
Manhattan, Kansas, USA
Is this poly phase? Could be a single phasing motor.

Check amp draw on each leg, for premature failure and to see if motor is overloaded mechanically.

Bearing will usually be a higher pitch, than an overloaded or weakening motor.


:cool

Just some thoughts.


#31749 - 12/04/03 03:53 PM Re: 10 hp Motor  
Crowbar  Offline
Member
Joined: Jan 2003
Posts: 33
Pittsburgh, PA,USA
A- Open shunt field. Motor would not run.

DC Shunt motor with open shunt field WILL run, away that is making a very distinct sound I might add.


#31750 - 12/05/03 12:46 AM Re: 10 hp Motor  
Scott35  Offline

Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA
How about:

* E. All Of The Above
* F. All Of The Above, Under Certain Circumstances
* G. If There Was A Description Of The Type Of Motor And The Load On Shaft, Answer May Be Derived
* H. All Of "A" Through "G"

I will choose "H"!!!

Keny, is this an exam question also?
If so, what is your answer and how did you arrive at it?

Scott35


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!


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