In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out. So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor. So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition.
Shashi singh In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out. So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor. So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition. Thank you for asking such a conceptual question so that other peoples concept will also clear by reading this question and answer.
Shashi singh In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out. So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor. So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition. Thank you for asking such a conceptual question so that other peoples concept will also clear by reading this question and answer.
last one is wrong because we can not draw N v/s T charecteristics... because Tproportional to Φ.Ia and Npro...to 1/Φ then in dc shunt motor Φ is contant then N is also constant... so that T is constant.....therefore we can't draw T N charecteristics
Flux is constant in DC Shunt Motor but speed N is not constant. Because speed N = Eb/flux fi. So if flux fi is constant then speed is directly proportional to Back emf Eb and therefore if back emf Eb changes due to change in armature current, (as back emf Eb=V - IaRa), speed N also changes. And armature torque T is product of Fi & armature current Ia. But if Flux fi is constant then armature torque Ta is directly proportional to Armature Current Ia. Therefore if armature current is varying, in the same proportion armature torque varies and therefore we can draw Speed Torque Characteristics in DC shunt Motor. Thank you for asking the question. - Electrical Academy
thank you sir your videos are very helpfull for my semester exam preparations!!
Nice explanation
Very nice explanation, Thankyou so much
Super continue like this only then only we can learn more
In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out.
So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor.
So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition.
sir equation se mat samjhao can u please explain practically if we remove supply from field winding how speed will increase to maintain back emf?/
Do you have English version of this lovely vedio?
Sir jbb N directly proportional hai armature current ka too phir speed increase hoga to current bhi to increase hona chaiya....?
Not N propotional to directly current inversly propotional current
Thanks sir
Good
Sir speed vs torque speed slightly decreases due to increase in torque or decrease in torque plz any one tell very cunfused of it
Ur explanation is too much good sir, thanku for making this video 🙏
Welcome sir
Sir dc sunt moter no load pr running kr rhi hai aur uska field vainding open ho jaye to moter pr Kya efact hoga
Shashi singh
In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out.
So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor.
So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition.
Thank you for asking such a conceptual question so that other peoples concept will also clear by reading this question and answer.
Shashi singh
In a DC shunt motor if you cut the supply for the field , the speed would dangerously increase in order to maintain the back emf of the motor as flux is inversely proportional to the speed of motor.So if flux drops to 0 speed will tend to infinity. practically it will damage the windings of the motor and also can break the shaft if the fuse doesn't blow out.
So fuse is provided in such cases or MCB's are connected which protects the motor from damage by closing the circuit. And starter which is provided to that DC shunt motor also work in that cases by deenergizing the hold on coil of starter and starter handle comes to its initial position to protect the motor.
So to protect from adverse effects, shunt field winding should not be removed when the dc shunt motor is at working condition.
Thank you for asking such a conceptual question so that other peoples concept will also clear by reading this question and answer.
Sir app ye nhi bataye kii armature current constant Kyu hota hai
sir please explain am so confused
last one is wrong because we can not draw N v/s T charecteristics... because Tproportional to Φ.Ia
and Npro...to 1/Φ then in dc shunt motor Φ is contant then N is also constant... so that T is constant.....therefore we can't draw T N charecteristics
Flux is constant in DC Shunt Motor but speed N is not constant. Because speed N = Eb/flux fi.
So if flux fi is constant then speed is directly proportional to Back emf Eb and therefore if back emf Eb changes due to change in armature current, (as back emf Eb=V - IaRa), speed N also changes.
And armature torque T is product of Fi & armature current Ia.
But if Flux fi is constant then armature torque Ta is directly proportional to Armature Current Ia. Therefore if armature current is varying, in the same proportion armature torque varies and therefore we can draw Speed Torque Characteristics in DC shunt Motor.
Thank you for asking the question.
- Electrical Academy
Sir I am mechanical engineering student
Subject basic electrical drive and control
Par video dalo
Please whats app or number email id I syllabus