A 220 V DC series motor runs drawing a current of 30 A from the supply. Armature and field circuit resistances are 0.4 22 and 0.12 respectively. The load torque varies as the square of the speed. The flux in the motor may be taken as being proportional to the armature current. To reduce the speed of the motor by 50% the resistance in ohms that should be added in series with the armature is

Q: Give the relevant details for drawing lap winding for a de machine with 4 poles, 22 slots and 6…

A: We need to give relevant details for drawing a lap winding for a dc machine having, Poles (P) = 4…

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Q: A 220 V series motor takes 15 A and runs at 700 rpm. The armature resistance including the…

A: The solution is given below

Q: A DC generator feeds a load of current 20 A and voltage 220 V. Calculate the electrical motive force…

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A:

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A: In this answer let us try to understand what are mechanical losses as explained below.

Q: A 250 V series motor has an armature resistance of 0.2 ohm and a series-field resistance of 0.18…

A:

DC Series Motors

A DC motor is a type of electric motor which converts electric energy into mechanical energy. The forces that are produced by the magnetic field are what those common types of motors rely upon. Either electro-mechanical or electronic, all types of DC motors have some internal mechanism to change the current direction in part of the DC motors. As the DC motors could be powered from existing DC lighting power distribution systems, these motors were the first form of motors widely used. By changing the strength of the current in its field winding or by using a variable supply voltage, the speed of the DC motors can be controlled over a wide range.