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Eligh
Lv 4
Eligh asked in Science & MathematicsEngineering · 9 years ago

DC motor question, help needed?

A 230V, 1KW , 4.34A motor with an armature resistance of 1 ohm. When supplied at 230V the unloaded motor runs at 900RPM, drawing a current of 0.6A. If the motor is run at 120V, calculate the approx no load speed and the accurate no load speed with bearing losses.

Thanks!

1 Answer

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  • Anonymous
    9 years ago
    Favorite Answer

    The speed of a DC motor is dependant on voltage.

    At roughly half the voltage it will run at roughly half the speed. It will be proportional.

    No load speed, taking losses into account will depend on the % loss, Friction, windage and copper.

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