What is the minimum conductor size for the PBB?

• A. #2 AWG or larger
• B. #4/0 AWG
• C. #6 AWG
• D. #8 AWG

Answer: (A)

Sizing the conductor for the PBB centers on ampacity—the wire must safely carry the expected current without overheating and with acceptable voltage drop. The PBB carries the power distribution required by the system, so the conductor must meet the current demands under normal operation and any charging or fault conditions. The minimum size is the smallest gauge that satisfies those ampacity requirements; anything smaller risks overheating, while larger gauges aren’t the minimum. Among the options, #2 AWG is the smallest size that meets the needed ampacity, while #6 and #8 are too small for typical PBB currents and #4/0 is larger than necessary for the minimum. Therefore, the minimum conductor size is #2 AWG or larger.