What is the full-load current of a 460 volt, 20 hp motor?

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To determine the full-load current of a 460 volt, 20 horsepower (hp) motor, you can use the formula that relates horsepower to current for three-phase motors. The formula is:

[ I = \frac{P \times 746}{\sqrt{3} \times V \times \text{efficiency}} ]

Where:

  • ( I ) is the full-load current in amperes

  • ( P ) is the horsepower (20 hp, in this case)

  • 746 is the number of watts per horsepower

  • ( V ) is the line voltage (460 V)

  • Efficiency is typically around 0.9 (90%) for a well-functioning motor but can vary.

Assuming an efficiency of about 0.9, the calculation would look like this:

  1. Convert horsepower to watts: ( 20 \times 746 = 14920 ) watts.

  2. Plug the values into the formula:

[ I = \frac{14920}{\sqrt{3} \times 460 \times 0.9} ]

Calculating ( \sqrt{3} ) gives approximately 1.732, and then:

[ I \approx \frac

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