For raceways containing ungrounded conductors, what is the minimum conductor size that needs protection when entering a cabinet or box?

In contexts involving raceways that contain ungrounded conductors, the National Electrical Code (NEC) specifies minimum requirements to ensure safe and effective operation. The choice of 4 AWG aligns with NEC guidelines regarding the protection of conductors entering cabinets or boxes.

When conductors are ungrounded, they still require adequate size to handle potential fault currents without risking overheating or failure. The 4 AWG size provides sufficient current-carrying capacity while also accommodating the necessary protection measures to prevent damage or hazardous conditions. This choice reflects concerns for both safety and compliance with code requirements for ungrounded systems, ensuring that the conductors are appropriately sized to handle the electrical load and any potential faults that could occur during operation.

Conductor sizes smaller than 4 AWG may not provide the necessary level of safety and could be insufficient in various scenarios involving fault conditions, leading to potential risks such as overheating or inadequate protection against short circuits. Therefore, 4 AWG is the minimum size that should be utilized in this context to ensure both safety and compliance with standards.