This is an exception to the electric code, not the rule. Almost every outlet must be paired with the appropriate wire size and breaker. A 30A outlet must be ba

This is an exception to the electric code, not the rule. Almost every outlet must be paired with the appropriate wire size and breaker. A 30A outlet must be backed with a 30A breaker (no exceptions!) and wire must be at least capable of carrying 30 amps. There's also restrictions on wire size based on the outlet/breaker, since certain breakers/outlets cannot handle certain wire sizes. For instance, NEMA 5-15 outlets generally can't support wire sizes above 12 gauge, so you're limited to 12 or 14 gauge only.