Stranded vs Solid Copper

sleepwalker65

There is only one correct breaker for each panel. That is the one that is the correct current rating (regular/GFCI/AFCI) specified by the manufacturer of your panel. Any other breaker is the wrong breaker. Period.

This is mistaken. There are instances where there are alternatives to using the OEM's breaker. For example, Siemens makes substitutes for some Square D breakers. UL listed, too. See this.

@towertone 60Hz and you’re talking about skin effect? Are you sure you’re an electrician?

Skin effect has zero role in signal transmission at audio frequencies. This is simply more snake oil promoted by cable manufacturers and their "believers." Cables are passive devices and as a result have a linear response. Only at very high frequencies, way beyond those of human hearing, does skin effect play a significant role.

I’d agree either stranded or solid should work the same. I’d use solid for internal box wiring and stranded for cables, based solely on flexibility.