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Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be?
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Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c....
Solution:
Given data:
- V = 250V
- Ra = 0.080 ohm
- Eb = 242V
- N1 = 1500 rpm
- I1 = 87A
Calculations:
1. The armature current Ia can be calculated using the equation,
V = Eb + IaRa
Therefore, Ia = (V - Eb) / Ra
Ia = (250 - 242) / 0.080
Ia = 100 A (approx.)
2. The torque developed by the motor is proportional to the armature current. Therefore, when the armature current is increased from 87 A to 100 A, the torque developed will also increase.
This will cause the speed of the motor to decrease.
3. The speed of the motor as a generator can be calculated using the equation,
Eb = (V - IaRa) / K
Where K is the motor constant.
The motor constant K can be calculated using the equation,
K = (Eb / N1)
Therefore, K = (242 / 1500)
K = 0.161 V/rpm
4. Substituting the values of V, Ra, Ia and K in the equation for speed,
N2 = (V - IaRa) / K
N2 = (250 - 100*0.080) / 0.161
N2 = 897 rpm (approx.)
Answer:
The speed of the machine as a generator will be 897 rpm (approx.).
Given data:
- V = 250V
- Ra = 0.080 ohm
- Eb = 242V
- N1 = 1500 rpm
- I1 = 87A
Calculations:
1. The armature current Ia can be calculated using the equation,
V = Eb + IaRa
Therefore, Ia = (V - Eb) / Ra
Ia = (250 - 242) / 0.080
Ia = 100 A (approx.)
2. The torque developed by the motor is proportional to the armature current. Therefore, when the armature current is increased from 87 A to 100 A, the torque developed will also increase.
This will cause the speed of the motor to decrease.
3. The speed of the motor as a generator can be calculated using the equation,
Eb = (V - IaRa) / K
Where K is the motor constant.
The motor constant K can be calculated using the equation,
K = (Eb / N1)
Therefore, K = (242 / 1500)
K = 0.161 V/rpm
4. Substituting the values of V, Ra, Ia and K in the equation for speed,
N2 = (V - IaRa) / K
N2 = (250 - 100*0.080) / 0.161
N2 = 897 rpm (approx.)
Answer:
The speed of the machine as a generator will be 897 rpm (approx.).
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Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be?
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Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be?.
Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be?.
Solutions for Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? in English & in Hindi are available as part of our courses for GATE.
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Here you can find the meaning of Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? defined & explained in the simplest way possible. Besides giving the explanation of
Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be?, a detailed solution for Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? has been provided alongside types of Q3. A 250V d.c shunt motor has Ra=0.080. When connected to a 250V d.c. supply it develop s back emf of 242 V at 1500 rpm. If the armature current is changed to 87 A, the speed of the machine as a generator will be? theory, EduRev gives you an
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