# Interpole flux should be sufficient to?

Interpole flux should be sufficient to neutralise both the armature reaction flux as well as commutating e.m.f. induced in the coil.

## Related questions

Last Answer : If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by Blv.

Description : Flux density formula

Last Answer : Flux density formula

Description : Define the following terms and state their units: (i) Luminous intensity, (ii) Luminous flux

Last Answer : i) Luminous intensity: This is defined as the luminous flux emitted into a solid angle of space in a specific direction. Its unit is the candela.  OR  The luminous flux per unit solid angle ( ... energy radiated by the light source in all direction. The unit of luminous flux is lumen (lm)

Description : Define the following terms: i) Magnetic flux density, ii) Reluctance, iii) Magneto-motive force, iv) Permeance.

Last Answer : (i) Magnetic flux density (B): It is the magnetic flux per unit area measured at right angles to the flux path. (Its unit is weber/m2 or tesla).  (ii) Reluctance: It is the ... flux to set up through it and it is reciprocal of reluctance. Permeance = 1/ Reluctance. Unit: weber/ampere.

Description : Describe the concept of leakage flux, useful flux and fringing with neat diagram.

Description : Define magnetic flux density and state its formula.

Last Answer : The magnetic flux per unit area is called as magnetic flux density. Magnetic flux density is denoted by B. The formula for magnetic flux density is Weber per metre square or Tesla. Mathematically ... the unit of magnetic flux density is Weber per metre square which is also called as Tesla.

Description : In an induction motor if the flux density is reduced to one-half, of its normal value then the torque will  (1) reduce to one-half (2) reduce to one-fourth (3) remain unchanged (4) increase four times

Last Answer : In an induction motor if the flux density is reduced.to one-half, of its normal value then the torque will reduce to one-fourth

Description : In a synchronous machine, if the field flux axis ahead of the armature field axis in the direction of rotation, the machine is operating as  (1) synchronous motor (2) synchronous generator (3) asynchronous motor (4) asynchronous generator

Last Answer : In a synchronous machine, if the field flux axis ahead of the armature field axis in the direction of rotation, the machine is operating as synchronous generator

Description : Which of the following is a unit of magnetic flux? A) Weber B) Maxwell C) Both A and B D) None of these

Last Answer : Which of the following is a unit of magnetic flux? A) Weber B) Maxwell C) Both A and B D) None of these

Description : It is possible to increase the field flux and, at the same time, increase the speed of a d.c. motor provided its .......... is held constant.

Last Answer : It is possible to increase the field flux and, at the same time, increase the speed of a d.c. motor provided its armature current is held constant.

Description : The property of a material which opposes the creation of magnetic flux in it is known as?

Last Answer : The property of a material which opposes the creation of magnetic flux in it is known as reluctance.

Description : The unit of magnetic flux is?

Last Answer : The unit of magnetic flux is weber.

Description : What is the permissible flux density in case of cold rolled grained oriented steel?

Last Answer : The permissible flux density in case of cold rolled grained oriented steel is 1.7 Wb/m2.

Description : The path of magnetic flux in a transformer should have?

Last Answer : The path of magnetic flux in a transformer should have low reluctance.

Last Answer : Flux density is denoted by B. And it is given as B = flux/ area Where, the unit of flux is Weber and unit of area is meter square. So the unit of flux density is weber per meter square which is also called as Tesla.

Description : The introduction of interpoles in between the main pole improves the performance of d.c. machines, because (A) The interpole produces additional flux to augment the developed torque. (B) The flux waveform is ... armature is removed. (D) A counter e.m.f. is induced in the coil undergoing commutation.

Last Answer : Ans: D Counter e.m.f is produced, it neutralizes the reactive emf.

Description : A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is  (A) 96 V (B) 192 V (C) 384 V (D) 768 V

Last Answer : A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is 384 V

Last Answer : In D.C. generators on no-load, the air gap flux distribution in space is flat topped.

Description : [53] The iron loss of the transformer is negligible during short circuit test because A. The entire input is just sufficient to meet Cu losses only B. Flux produced is a small fraction of the normal flux C. Iron core becomes fully saturated D. Supply frequency is held constant

Last Answer : B. Flux produced is a small fraction of the normal flux

Description : As shown in the illustration, part 'X' of the diagram is known as a/an _____________. EL-0052 A. commutator B. interpole C. starting pole D. auxiliary pole

Description : Sparking at the brushes of a DC propulsion motor can be the result of ____________. A. improper brush pressure B. improper brush seating C. reversed interpole polarity D. all of the above

Description : Which of the listed conditions could cause a DC motor to have excessively hot windings and sparking at the brushes? A. Reversed interpole polarity B. High bar-to-bar voltage C. Loose brushes D. Excessive humidity

Description : As shown in the illustration, the motor generator(M-G) set's three-phase motor drives the ______________. EL-0101 A. motor and the generator B. motor and the exciter C. generator and the exciter D. main field and the interpole field

Description : The direction of rotation of a DC propulsion motor can be changed by reversing the _____________. A. brush holder position B. polarity of the field poles C. brush staggered order D. motor interpole connections

Description : Sparking of D.C. motor brushes can be caused by __________. A. an open commutating winding B. many mechanical, electrical or operating faults C. an open interpole D. all of the above

Description : As shown in the illustration, the M-G set's three-phase motor drives the ______________. EL-0101 A. motor and the generator B. motor and the exciter C. generator and the exciter D. main field and the interpole field

Description : In the construction of D.C. motors, parts of both the series and shunt fields are wound on the _____________. A. opposite main pole B. rotor core C. interpole D. same main pole

Description : Relative to the direction of rotation, a D.C. motor commutating pole has the same polarity as the _____________. A. main pole following B. interpole following C. main pole preceding D. interpole preceding

Description : One method of testing for a reversed shunt field coil in a DC generator or motor is by connecting the field to a direct current source, at reduced field rated voltage, and test for ... placed near each field C. test lamp across adjacent fields D. copper jumper across the interpole connections

Description : A ground can be defined as an electrical connection between the wiring of a motor and its ____________. A. shunt field B. circuit breaker C. metal framework D. interpole

Description : What current flows in the interpole windings?

Description : If we have 30kva, 250 kva, 300kva d.g set than how many earthing we do?

Last Answer : We should have two distinct earthing for neautral earthing and two for Body earthing.To achieve minimal resistance neautral earthpit should be connected in parallel.similarly body earthing too.

Description : The voltage built-up process of a d.c. generator is  1. difficult 2. delayed 3. cumulative 4. Infinite

Last Answer : The voltage built-up process of a d.c. generator is cumulative

Description : for the voltage built-up a self-excited D.C. generator, which of the following is not an essential condition.  1.there must be some residual flux  2.field winding mmf must aid the residual ... 3.total field circuit resistance must be less than t critical value  4.armature speed must be very high

Last Answer : for the voltage built-up a self-excited D.C. generator, which of the following is not an essential condition.  1.there must be some residual flux  2.field winding mmf must aid the ... .total field circuit resistance must be less than t critical value  4.armature speed must be very high

Description : The slight curvature at the lower end of the O.C.C. of a self-excited dc generator is due to  1. residual pole flux 2. high armature speed 3.magnetic inertia 4. high field circuit resistance

Last Answer : The slight curvature at the lower end of the O.C.C. of a self-excited dc generator is due to magnetic inertia

Description : In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will   (a) Improve but terminal voltage will fall   (b) ... will fall   (c) Improve and terminal voltage will rise   (d) worsen and terminal voltage will rise

Last Answer : In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will Improve but terminal voltage will fall

Description : The terminal voltage of a DC shunt generator drops on load because of all of the following except : (A) Armature reaction (B) Armature resistance drop (C) Commutation (D) Field weakening due to armature reaction and armature resistance drop

Last Answer : (D) Field weakening due to armature reaction and armature resistance drop

Last Answer : If  equalising bar is connected to the 2 DC generators  the current will be equal in 2 generators irrespective of parallel connection so that we connect equaliser bar

Last Answer : The critical resistance of the D.C. generator is the resistance of field.

Last Answer : Wave winding is composed of that even number which is exact multiple of poles + 2.

Last Answer : Armature reaction in a generator results in demagnetisation of leading pole tip and magnetisation of trailing pole tip.

Description : If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be?

Last Answer : If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be zero.

Last Answer : In a separately excited generator supplying rated load the armature reaction is always present.

Last Answer : A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be about 2 V.

Description : A sinusoidal voltage of 5 Hz is applied to the field of a shunt generator. The armature voltage wave?

Last Answer : A sinusoidal voltage of 5 Hz is applied to the field of a shunt generator. The armature voltage wave will be of 5 Hz.

Last Answer : In a level compounded D.C. generator, full load terminal voltage is equal to no-load terminal voltage.

Last Answer : In over compounded generator, full load terminal voltage is more than no load terminal voltage.

Last Answer : In case of a flat compounded generator voltage remains constant irrespective of the load.

Last Answer : An exciter for a turbo generator is a shunt generator.

Last Answer : In a D.C. generator in case the resistance of the field winding is increased, then output voltage will decrease.