A residential electrical panel has conduit filled to 80% of its capacity. The conduit is 1-inch rigid metal conduit. How many 12-gauge THHN conductors can be installed in the conduit?
- A10 conductors
- B12 conductors
- 15 conductors
- D20 conductors
Exam tip
Always check the conduit fill tables in the NEC for the correct number of conductors.
Why C is correct
According to 2026 NEC Article 318.10, 1-inch rigid metal conduit can contain 15 12-gauge conductors at 80% fill. The correct answer is 15 conductors.