What is the minimum size SO cord permitted containing conductors for a motor rated at 5 hp and supplied by a 120/208-V, 3-ph, 4-W panel?

To determine the minimum size of SO (Service-Optional) cord permitted for a 5 hp motor supplied by a 120/208-V, 3-phase, 4-W panel, it's essential to consider both the rated specifications of the motor and the relevant electrical codes.

For a motor rated at 5 hp operating at 208 volts in a three-phase system, it’s important to understand the current draw of the motor, which can typically be calculated or obtained from motor tables. In general, a 5 hp motor at 208 V would have a full load current of approximately 15.2 amperes.

The National Electrical Code (NEC) provides guidelines on conductors' minimum sizes to handle the electrical load safely. Given that SO cords are a flexible type of cord used for motors and other equipment, they have specific requirements regarding the minimum size based on the service conditions, including amperage and operating temperature.

Considering the typical ampacity tables that apply to SO cords, the minimum size that would accommodate the full-load current safely is based on the continuous ratings and derating factors as per the NEC, which can essentially validate that 11 AWG is a suitable size for this application.

In summary, a minimum size of 11 AW