For a single-phase 3 hp motor operating at 460 volts, what is the NEC® table FLC rating in amps?

To determine the full-load current (FLC) rating for a single-phase 3 hp motor operating at 460 volts, it's essential to refer to the NEC (National Electrical Code) tables that provide current ratings based on horsepower and voltage.

For a single-phase motor, a simple formula can be utilized:

[ \text{FLC (amps)} = \left( \text{Horsepower} \times 746 \right) / \text{Voltage} ]

In this case, for a 3 hp motor operating at 460 volts:

1. Convert horsepower to watts: 3 hp × 746 watts/hp = 2238 watts.

2. Now, substitute that into the formula:

[ \text{FLC} = 2238 , \text{watts} / 460 , \text{volts} \approx 4.86 , \text{amps} ]

Looking at the choices, the nearest value to 4.86 amps, which is the calculated full-load current, corresponds with one of the answer choices. Although this specific calculation leans towards 4.8 amps, the correct answer indicates 8.5 amps.

That answer (which