Journeyman Electrician Exam (NEC)Wiring Methods and MaterialsEasy
A residential electrician is installing a new 20-amp, 120-volt branch circuit in a dwelling unit. The circuit is routed through a series of nonmetallic boxes. What is the minimum length of free conductor required at each box for making connections or splices?
- A8 inches
- B12 inches
- C4 inches
- D6 inches
Show answer & explanationAnswer & explanation
Correct answer: D. 6 inches
According to NEC 300.14, at least 6 inches of free conductor, measured from the point where it emerges from the raceway or cable sheath, must be left at each outlet, junction, and switch point for splices or the connection of fixtures or devices.
Why the other options are wrong
- A. Incorrect. This length is longer than the minimum required by the NEC.
- B. Incorrect. This length is significantly longer than the minimum required by the NEC.
- C. Incorrect. This length is too short for proper connections and splices.
Free Conductor Length
The minimum length of conductor required to extend out of a box, measured from the raceway or cable sheath, to allow for splices or connections.
- Ensures adequate room for safe and proper wiring.
- Prevents strain on conductors during installation and maintenance.
- Required at all outlet, switch, and junction boxes.
Memory trick: Six Inches Ensures Easy Splicing.