A 10 kilowatt 100 volt 1,000 rpm dc machine has an armature resistance of 0.09 ohm...
A 10 kilowatt 100 volt 1,000 rpm dc machine has an armature resistance of 0.09 ohm and is connected to a 100 V dc supply.
1.2.1 Determine the starting current and the rated current if no starting resistance is used in the armature circuit.
1.2.2 Determine the value of the starting resistance if the starting current is limited to twice the rated current. (1 mark)
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A 10 kilowatt 100 volt 1,000 rpm dc machine has an armature
resistance of 0.09 ohm...
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FQ3
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3. A 25-kW, 230-V shunt motor has an armature resistance of 0.064 Ω and a field-circuit resistance of 95 Ω. The motor delivers rated output power at rated voltage when its armature current is 122 A. When the motor is operating at rated voltage, the speed is observed to be 1150 r/min when the machine is loaded such that the armature current is 69.5 A a. Calculate the rated-load speed of this motor In order to protect both the motor...
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