Which branch-circuit rating is NOT permitted for lighting and receptacle circuits in dwelling unit(s)?

The branch-circuit rating that is not permitted for lighting and receptacle circuits in dwelling units is 25 A. In residential electrical installations, the National Electrical Code (NEC) provides specific guidelines for the ratings of circuits to ensure safety and functionality.

Lighting and general-purpose receptacle circuits in dwelling units are typically rated at 15 A and 20 A. The reason for this standardization is to ensure that circuits can handle typical household loads without the risk of overheating or creating safety hazards. A 30 A circuit is generally reserved for applications that require a higher current, such as larger appliances or specialized equipment, and is not suitable for general lighting or receptacle use in a dwelling.

Since 25 A does not conform to the accepted ratings for lighting and receptacle circuits, it is considered inappropriate and thus not allowed in standard residential electrical configurations. This regulation helps to maintain a uniform safety standard across residential wiring systems.