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Full-load current for single-phase AC motor

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    Full-load current for single-phase AC motor

    The full-load current for a single-phase alternating current 115 volt, 1 horsepower motor is which of the following:

    Gonna need motor efficiency and power factor to calculate the answer.

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    Quote Originally Posted by test11 View Post
    The full-load current for a single-phase alternating current 115 volt, 1 horsepower motor is which of the following:

    Gonna need motor efficiency and power factor to calculate the answer.
    Answer comes from NFPA 70 Table 430.248: 16A at 115V for single phase 1HP motors. I'm not sure how they calculate this without the values you mentioned. Maybe they use a standard efficiency and PF constant?

    1HP motors have a typical PF of 0.84 based on this: https://www.engineeringtoolbox.com/p...tor-d_654.html

    Using that info and an Efficiency of 50% gets you close using this calculator: https://goodcalculators.com/motor-fla-calculator/

    Anyone know how NFPA gets these values?

    Click image for larger version. 

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