What size conductor is required in each conduit feeding a 600-A panel from a transformer in the given scenario?

To determine the required size of conductors for feeding a 600-A panel from a transformer, it’s important to reference the National Electrical Code (NEC) standards and the ampacity tables for conductors. The size of the conductor must not only support the current load but also take into account factors such as conductor type, insulation rating, and ambient temperature.

For a 600-A load, using the NEC ampacity tables for copper conductors, typically, a minimum of 3/0 AWG is appropriate when considering the standard installation conditions and continuous load requirements. This size ensures that there is sufficient current carrying capacity to handle the electrical demand without overheating the conductors.

Additionally, the choice of conductor must factor in the location, installation methods, and any adjustments required for multiple conductors in a raceway. When these conditions are considered, 3/0 AWG emerges as a typical choice for a 600-A feeder from a transformer, effectively balancing safety and code compliance.

The other options would either be insufficient for carrying the necessary load or excessive, which could introduce unnecessary cost and complexity. Thus, selecting 3/0 AWG as the conductor size helps maintain electrical efficiency, safety, and compliance with electrical code requirements.