The electrical inspector is inspecting the wiring methods in an existing residential dwelling and comes across a section of electrical wiring that is run through a metal conduit. Which of the following is the correct requirement for the wiring method according to the 2023 NFPA 70 NEC?
- AThe wiring method must be Type MC cable.
- BThe wiring method must be Type NM cable.
- The wiring method must be Type THWN cable.
- DThe wiring method must be Type UF cable.
Exam tip
Familiarize yourself with the requirements for wiring methods in metal conduits as specified in the NEC.
Why C is correct
According to Section 330.30(B) of the 2023 NEC, when wiring is run through metal conduit, it must be Type THWN cable. Type MC cable (Option A) is suitable for direct burial but not for conduit runs, Type NM cable (Option B) is for non-metallic sheathed cable, and Type UF cable (Option D) is for underground installations.