Technically, stranded wire has a slightly larger diameter than solid wire of the same gauge to account for air gaps between strands. However, the ampacity remains the same. A 12 AWG solid wire and a 12 AWG stranded wire can carry the same amount of current.
There are two primary systems used globally to measure cable size: cable size chart
(critical for long runs). If length >20m (for low voltage) or >50m (for 230V), go up one or two sizes. Technically, stranded wire has a slightly larger diameter
Whether you are a DIY enthusiast rewiring a lamp, a solar enthusiast setting up an off-grid system, or a professional electrician planning a new circuit, one question is more critical than any other: 20m (for low voltage) or >