What causes stator failure?

What causes stator failure?
by

4 Answers

Answer :

Speed of the motor increases rapidly


by

Answer :

When the load supplied by the motor decreases abruptly but the voltage is kept constant this may cause overheating of the stator winding leading to failure of the stator.
by

Answer :

Enough rate of current flow instead heavy current flow in the conductor causes stator failure due to heat(temperature) increase.
by

Answer :

Stator faliur due to moistur. Due to priodically heatup of winding.
by

Related questions

What is a stator in a motor?

Description : What is a stator in a motor?

Last Answer : Stator is the stationary part of the electrical machine both motor and generator. In motor it provide the rotating magnetic field to drive rotor and in case of generator stator convert rotating magnetic field into current.

State the function of following parts in Induction motor. (i) Stator (ii) Slip rings

Description : State the function of following parts in Induction motor. (i) Stator (ii) Slip rings

Last Answer : Name of part Function Stator 1) Stator frame supports the core, terminal box and protects the inner parts. 2) Stator core houses stator winding. 3) Stator winding ... ) Provides facility to connect external resistance to rotor circuit through brushes for starting and control.

A _________ is used to measure the stator % winding temperature of the generator.

Description : A _________ is used to measure the stator % winding temperature of the generator.  (A) Thermocouple (B) Pyrometer (C) Resistance thermometer (D) Thermometer

Last Answer : A Resistance thermometer is used to measure the stator % winding temperature of the generator. 

The stator of phase shifting transformer for use in conjunction with an A.C. potentiometer usually has a?

Last Answer : The stator of phase shifting transformer for use in conjunction with an A.C. potentiometer usually has a two-phase winding.

The purpose of stator winding in the compensated repulsion motor is to?

Last Answer : The purpose of stator winding in the compensated repulsion motor is to improve power factor and provide better speed regulation.

An electric motor in which both stator field and rotor rotates with same speed is called?

Description : An electric motor in which both stator field and rotor rotates with same speed is called?

Last Answer : An electric motor in which both stator field and rotor rotates with same speed is called synchronous motor.

Will you share how a past failure helped you succeed?

Description : Will you share how a past failure helped you succeed?

Last Answer : As in succeeding in life or succeed in obtaining wealth or a job? Not sure what you would quantify as success.

What are your thoughts on the FAILURE of Trumpcare?

Description : What are your thoughts on the FAILURE of Trumpcare?

Last Answer : Great delight! It was a cruel, cruel bill.

How will you get over yourself from such failure?

Description : How will you get over yourself from such failure?

Last Answer : answer:Your question is very specific. I can only think of general answers. First, every human being is flawed. Even your greatest heroes aren't perfect. We can all inspire one another without having to be ... is your own best self and not an imitation of someone else. Third, you're not through yet.

Do you feel like a failure?

Description : Do you feel like a failure?

Last Answer : I’ve yet to achieve the Oliver Twist award for getting Great Answered on an orphaned question, so I am a Fluther failure.

Fuel Pump Failure

Description : Fuel Pump Failure

Last Answer : Is your car having acceleration problems? Has there been an occasion when your car simply sputtered and died while on the road? If your answer is yes, then you may want to check your car for fuel pump ... a fuel pump is to take your car to a repair shop where professionals can do it for you.

Was there any feat that you wanted to achieve as a youngster?

Description : Was there any feat that you wanted to achieve as a youngster?

Last Answer : To be academicly advanced to university. From grade 5.

What was the last thing you failed at, did you try again, and what did you do differently the second time?

Description : What was the last thing you failed at, did you try again, and what did you do differently the second time?

Last Answer : I failed grade 12 math, so I took the multiple choice test over and over until statistically I would pass. Exactly 50% to pass. Got my advanced high school diploma and went to university.

Have you wasted your potential? If so, does that bother you?

Description : Have you wasted your potential? If so, does that bother you?

Last Answer : I think so. It bothers me every once in a while when I’m the what if mode. But not so much anymore as I’ve pretty much ended up where I think I was going to end up anyway—I just didn’t do it as a doctor. I did it as a nurse instead. I could have done so much more as a doctor.

Can stereotyping be a positive thing sometimes?

Description : Can stereotyping be a positive thing sometimes?

Last Answer : If you see a ‘gang’ coming towards you and assume they will hurt you, and you end up getting home safe because of your stereotyping, I guess that would be a positive.

When in your opinion can a person really give up on himself? At what point can he say that it's not worth even trying?

Description : When in your opinion can a person really give up on himself? At what point can he say that it's not worth even trying?

Last Answer : Probably when it’s causing more physical harm than good, then it’s time to call it quits.

How many corporations failed in the U.S. in 2010?

Description : How many corporations failed in the U.S. in 2010?

Last Answer : Not sure if some government agency tracks this number. It would be very difficult to keep track of, as it would have to include every Joe-Schmo who started up a business off some asinine idea ... for instance had a painting business one summer. Incorporated and everything. Didn't even last a year.

Did Gordon Gekko have something: ”....Greed, for lack of a better word, is good. Greed is right, greed works.”?

Description : Did Gordon Gekko have something: ”....Greed, for lack of a better word, is good. Greed is right, greed works.”?

Last Answer : Yes. Yes he did.

Do some people hate success in others?

Description : Do some people hate success in others?

Last Answer : There are people all over the place who can’t succeed themselves and therefore envy others and want to see them brought down / discouraged at the very least. And yeah, they feel like losers so they want the contaminate the rest of the world with their feelings. They are the people you need to avoid.

What are other examples of where "new and improved" may not always be better?

Description : What are other examples of where "new and improved" may not always be better?

Last Answer : answer:Cosmetic surgery :(

Is there something you would like to do, but are afraid you might fail?

Description : Is there something you would like to do, but are afraid you might fail?

Last Answer : Call a talk show on the radio. I am afraid I will say something stupid and forever brand myself as the ‘Idiot’ who made a arse of himself on the air.

Why can't we value failures for their ability to contribute to our future success?

Description : Why can't we value failures for their ability to contribute to our future success?

Last Answer : Most people do – they refer to it as “experience”. Most very experienced people have hit the deck a few times.

Have you ever been afraid to do something (thinking that you'd fail), but, when you pushed yourself to do it, you realized that it wasn't so difficult afterall and your effort proved to be successful?

Description : Have you ever been afraid to do something (thinking that you'd fail), but, when you pushed yourself to do it, you realized that it wasn't so difficult afterall and your effort proved to be successful?

Last Answer : Yes, my job dispatching. I originally turned it down, thinking I’d never be able to remember 30+ pick-up routes. Now I could do it in my sleep.

Has the fear of failing prevented you from trying to achieve something in your life?

Description : Has the fear of failing prevented you from trying to achieve something in your life?

Last Answer : So much. I consider it one of my worst flaws.

Experience is simply the name we give our mistakes?

Description : Experience is simply the name we give our mistakes?

Last Answer : I like to think that some of my experiences have been positive :)

The rotor impedance of a slip ring induction motor is (0.1 + j0.6)Ohm/ ph . The resistance/ph to be inserted

Description : The rotor impedance of a slip ring induction motor is (0.1 + j0.6)Ohm/ ph . The resistance/ph to be inserted into rotor to get maximum torque at starting should be

Last Answer : The rotor impedance of a slip ring induction motor is (0.1 + j0.6)Ohm/ ph . The resistance/ph to be inserted into rotor to get maximum torque at starting should be 0.5 Ohm

What is the rotor of a motor?

Description : What is the rotor of a motor?

Last Answer : Rotor is the rotating or moving part in motor and generator.

Voltage failure of an AC generator may be caused by ____________. A. failure of the exciter generator B. a tripped bus circuit breaker C. high mica segments on the stator bus bar D. excessive prime mover speed

Description : Voltage failure of an AC generator may be caused by ____________. A. failure of the exciter generator B. a tripped bus circuit breaker C. high mica segments on the stator bus bar D. excessive prime mover speed

Last Answer : Answer: A

Which type of protection is provided on a generator to protect against stator insulation failure?

Description : Which type of protection is provided on a generator to protect against stator insulation failure? A) Differential protection B) Overcurrent relay C) Thermocouple actuated alarm D) Reverse power relay

Last Answer : Which type of protection is provided on a generator to protect against stator insulation failure? A) Differential protection B) Overcurrent relay C) Thermocouple actuated alarm D) Reverse power relay 

A synchronous motor maintains synchronism with the rotating field because _____________. A. field strength varies directly with rotor slip B. DC current applied to the rotor coils causes the rotor magnets to lock in with the rotating flux of the stator C. the stator poles are dragged around due to the flux created by the excitation current D. the stator flux rotates in the opposite direction

Description : A synchronous motor maintains synchronism with the rotating field because _____________. A. field strength varies directly with rotor slip B. DC current applied to the rotor coils causes the rotor ... the flux created by the excitation current D. the stator flux rotates in the opposite direction

Last Answer : Answer: B

stator What ?

Last Answer : Alternator Fixed Part of it Stator Says.

Voltage build up in an isolated induction generator depends on A. Capacitor bank value B. Residual magnetism of the rotor iron C. Residual magnetism of the stator iron a) A, B b) A, B, C c) B d) A, C

Description : Voltage build up in an isolated induction generator depends on A. Capacitor bank value B. Residual magnetism of the rotor iron C. Residual magnetism of the stator iron a) A, B b) A, B, C c) B d) A, C

Last Answer : Ans: A

As shown in the illustration, the purpose of the item labeled 'Z', in assembly No. 2, is to _____________. EL-0001 A. keep the rotor in balance B. align the rotor to the stator C. dynamically balance the rotor D. cool the motor

Description : As shown in the illustration, the purpose of the item labeled 'Z', in assembly No. 2, is to _____________. EL-0001 A. keep the rotor in balance B. align the rotor to the stator C. dynamically balance the rotor D. cool the motor

Last Answer : Answer: D

Which of the following statements describes what will occur if the motor shown in the illustration is required to carry 150% of full load? EL-0056 A. The primary counter emf will be increased. B. The stator current will increase. C. The slip will decrease. D. The slip value, stator current curve, and torque curve will all coincide.

Description : Which of the following statements describes what will occur if the motor shown in the illustration is required to carry 150% of full load? EL-0056 A. The primary counter emf will be increased. B. ... slip will decrease. D. The slip value, stator current curve, and torque curve will all coincide.

Last Answer : Answer: B

The torque and current curves for a three-phase induction motor with a cage rotor, are shown in the illustration. Which of the following statements is true concerning the depicted curves? EL-0056 A. As slip increases, rotor reactance decreases. B. The pullout point on the torque curve is about seven times the normal full load torque value. C. At stand still, stator current is 150% of normal. D. If the motor is loaded to the point where 40% slip has resulted, it will stall.

Description : The torque and current curves for a three-phase induction motor with a cage rotor, are shown in the illustration. Which of the following statements is true concerning the depicted curves? EL-0056 A. As slip ... D. If the motor is loaded to the point where 40% slip has resulted, it will stall.

Last Answer : Answer: D

On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point to prevent the formation of condensation C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Description : On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point ... C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Last Answer : Answer: B

Which of the following is a characteristic of fractional horsepower repulsion start motors? A. They start with a rotating stator field. B. The short circuiting ring is removed from the commutator while starting. C. The brushes are removed from the commutator while starting. D. They have a low starting torque.

Description : Which of the following is a characteristic of fractional horsepower repulsion start motors? A. They start with a rotating stator field. B. The short circuiting ring is removed from the commutator while ... brushes are removed from the commutator while starting. D. They have a low starting torque.

Last Answer : Answer: B

The speed of a squirrel-cage, multi-speed, induction motor, as used aboard ship, is varied by changing the __________. A. number of connected poles in the stator B. frequency to the motor C. excitation voltage D. resistance of the rotor circuit

Description : The speed of a squirrel-cage, multi-speed, induction motor, as used aboard ship, is varied by changing the __________. A. number of connected poles in the stator B. frequency to the motor C. excitation voltage D. resistance of the rotor circuit

Last Answer : Answer: A

Air gap readings for electrical generating equipment should be taken periodicly. This is to _______. I. determine the condition of the bearings II. prevent damage to the rotor and stator A. I only B. II only C. both I and II D. neither I or II

Description : Air gap readings for electrical generating equipment should be taken periodicly. This is to _______. I. determine the condition of the bearings II. prevent damage to the rotor and stator A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: C

The purpose of the item labeled 'Z' in assembly No. 2, shown in the illustration is to _____________. EL-0001 A. keep the rotor in balance B. align the rotor to the stator C. dynamically balance the rotor D. cool the motor

Description : The purpose of the item labeled 'Z' in assembly No. 2, shown in the illustration is to _____________. EL-0001 A. keep the rotor in balance B. align the rotor to the stator C. dynamically balance the rotor D. cool the motor

Last Answer : Answer: D

A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature

Description : A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature

Last Answer : Answer: C

A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Description : A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Last Answer : Answer: C

A three-phase, squirrel cage, induction motor will run hot due to _____________. A. open stator coils B. high power factor C. dirty or corroded slip rings D. reversed commutating poles

Description : A three-phase, squirrel cage, induction motor will run hot due to _____________. A. open stator coils B. high power factor C. dirty or corroded slip rings D. reversed commutating poles

Last Answer : Answer: A

In the illustrated device, the part labeled '1A' _________. EL-0001 A. are start and run windings for a single phase shaded pole induction motor B. is the stator for a polyphase induction motor C. is the armature for a squirrel cage rotor motor D. are direct current shunt field windings for a universal motor

Description : In the illustrated device, the part labeled '1A' _________. EL-0001 A. are start and run windings for a single phase shaded pole induction motor B. is the stator for a polyphase induction ... armature for a squirrel cage rotor motor D. are direct current shunt field windings for a universal motor

Last Answer : Answer: B

In the illustrated motor, roller bearings are used because __________. EL-0001 A. of their ability to absorb moderate thrust loads B. they electrically insulate the rotor from the frame reducing cross-currents C. the shafting and end bells do not require as close a tolerance to properly fit this type of bearing D. the clearance between the rotor and stator is generally as close as mechanical tolerance will permit

Description : In the illustrated motor, roller bearings are used because __________. EL-0001 A. of their ability to absorb moderate thrust loads B. they electrically insulate the rotor from the frame reducing ... clearance between the rotor and stator is generally as close as mechanical tolerance will permit

Last Answer : Answer: D

The air gap in an induction motor should be periodically checked with a feeler gage to prevent possible ___________. A. rotor contact with the stator B. axial misalignment of the rotor C. damage to the motor bearings D. electrical damage to the bearings

Description : The air gap in an induction motor should be periodically checked with a feeler gage to prevent possible ___________. A. rotor contact with the stator B. axial misalignment of the rotor C. damage to the motor bearings D. electrical damage to the bearings

Last Answer : Answer: A

The rotation of a three-phase induction motor can be reversed by _____________. A. interchanging any two of the three line leads to the stator B. disconnecting one of the three line leads to the stator C. switching the shunt field coil leads D. permanently disconnecting any two of the three line leads to the stator

Description : The rotation of a three-phase induction motor can be reversed by _____________. A. interchanging any two of the three line leads to the stator B. disconnecting one of the three line leads to the ... the shunt field coil leads D. permanently disconnecting any two of the three line leads to the stator

Last Answer : Answer: A

The speed of a multi-speed, squirrel-cage, induction motor operating in a fixed frequency system can be changed by _____________. A. reconnecting stator windings for different numbers of poles B. changing the RPM of the rotor flux C. changing the phase sequence of the applied voltage D. reconnecting the stator so that no poles have the same polarity

Description : The speed of a multi-speed, squirrel-cage, induction motor operating in a fixed frequency system can be changed by _____________. A. reconnecting stator windings for different numbers of poles B. ... sequence of the applied voltage D. reconnecting the stator so that no poles have the same polarity

Last Answer : Answer: A

The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Description : The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Last Answer : Answer: C

In a compound-wound motor, a portion of the line current flows through the _____________. A. inertial poles B. stator C. shunt field coils D. frame

Description : In a compound-wound motor, a portion of the line current flows through the _____________. A. inertial poles B. stator C. shunt field coils D. frame

Last Answer : Answer: C