For a 15 HP, 460 volts motor showing an FLA of 18 amps, what is the minimum size SOO cord required?

To determine the minimum size SOO cord required for a 15 HP, 460 volts motor with a full load amperage (FLA) of 18 amps, it's essential to consider the National Electrical Code (NEC) guidelines for conductors. The NEC provides tables that outline the appropriate wire sizes based on the current carrying capacity, which reflects not only the motor's full load amperage but also the insulation type and installation conditions.

For a motor with an FLA of 18 amps, generally, the conductor must have a sufficient ampacity to safely carry this current under typical operating conditions while being compliant with the NEC. In most scenarios, the 60℃ rating of SOO cord requires a higher gauge wire to accommodate higher current draws safely.

When applying the ampacity tables, a wire size of 10 gauge is often identified as the minimum to safely handle the 18 amps, as it provides an adequate safety margin and helps prevent overheating. In fact, the 10 gauge cord can safely handle considerably more than 18 amps, thereby ensuring reliable operation of the motor.

When analyzing the other choices, options that are lower than 10 gauge would likely not have sufficient ampacity for the 18-amp load, potentially leading to