What minimum size starter is required for a 10 hp, 3-phase, 230/460-volt motor to be operated at 460 volts?

To determine the minimum size starter required for a 10 hp, 3-phase, 230/460-volt motor operating at 460 volts, it's fundamental to refer to the National Electrical Code (NEC) and industry standards, which dictate that motor starters must be appropriately sized based on the horsepower (hp) of the motor.

For a 10 hp motor, the general guideline is to use a starter that can handle the starting and running current of the motor. In the case of a 10 hp, 3-phase motor at 460 volts, the full-load current can be found in industry standard tables. Typically, for a 10 hp motor at this voltage, the full-load current is approximately 12.1 amps to 13.5 amps depending on specific manufacturer specifications.

Motor starters are typically rated by size, and in many industrial applications, size classifications range from 0 through 7, with size 0 starters designed for smaller motors and size 3 being used for motors larger than 10 hp. Since a 10 hp motor falls within the range suitable for a size 1 starter, this would be the minimum compliant choice to ensure reliable operation without risk of overload or failure.

Thus, the selection of a size