For the same cross-sectional area and material, which has a higher current-carrying capacity: a single-core cable or a multi-core cable? Why?

Answer: Single-core cables have a higher current carrying capacity.

The reasons are as follows:

  A single-core conductor contains only one wire, offering ample space and rapid heat dissipation. In contrast, a multi-core conductor consists of multiple conductors enclosed within a single sheath, leading to mutual heat accumulation and poor heat dissipation. Consequently, multi-core conductors are prone to heat buildup and temperature rise; for safety purposes, the national standard mandates a reduction in the allowable current-carrying capacity. 

 Additionally, a single-core conductor exhibits uniform electric field distribution and eliminates electromagnetic interference between conductors, resulting in more stable current transmission.

  Therefore, under identical specifications, the current-carrying capacity of a single-core cable exceeds that of a multi-core cable. For instance, the PV1F/H1Z2Z2K photovoltaic DC single-core cable produced by Shenghua Cable demonstrates more stable current-carrying performance thanks to its superior heat dissipation design and high-quality insulating sheath, making it better suited for high-current, long-distance, and highly reliable applications in photovoltaic and energy storage systems.