Bathroom vanity receptacle box at trim-out
What's wrong here?
- The conductors are too short to leave the free length the Code requires
- A bathroom receptacle must be at least 3 ft away from the sink
- The bare grounding conductor must be green insulated inside the box
- Nothing. This installation is compliant
Show the answer and the code reference
The answer
The conductors were trimmed so short that they barely reach the face of the box, well under the 6 in of free conductor (and 3 in outside the opening) that 300.14 requires.
Correct choice: 1. The conductors are too short to leave the free length the Code requires
300.14 requires at least 6 in of free conductor, measured from where the conductor leaves the cable sheath inside the box, at every outlet, junction, and switch point. Because a single-gang opening is smaller than 8 in in every dimension, each conductor also has to reach at least 3 in past the opening. Short leads get stripped and terminated under tension, the insulation gets nicked by the box edge, and the next person cannot remake the connection without splicing in more wire.
How to fix it
If there is slack in the cable, pull more of it into the box so there is 6 in of free conductor and the sheath still extends at least 1/4 in inside the box and past any clamp (314.17). Otherwise splice listed pigtails of the same size inside the box (watching box fill under 314.16) or replace the cable run.
Code references
NEC 2023 300.14 — Length of Free Conductors at Outlets, Junctions, and Switch Points
At least 6 in of free conductor, measured from the point where it emerges from its raceway or cable sheath, must be left at each outlet, junction, and switch point for splices or for connecting luminaires or devices. Where the box opening is less than 8 in in any dimension, each conductor must be long enough to extend at least 3 in outside the opening.
Drills citing 300.14NEC 2023 314.17 — Conductors Entering Boxes, Conduit Bodies, or Fittings
Where NM cable enters a box, the sheath must extend at least 1/4 in inside the box and beyond any cable clamp.
Drills citing 314.17
2026 NEC:same rule and number. Rule and number unchanged as far as found: the 6 in. free-conductor and 3 in. past-the-opening requirements remain in 300.14, and no 2026 change summary reported a revision (the last change was the 2023 'spliced or unspliced' sentence). Confidence: medium
Minnesota
Minnesota adopted the 2023 NEC without amendment as the Minnesota Electrical Code (Minn. Rules 1315.0200; Minn. Stat. 326B.35), effective July 1, 2023, so 300.14 and 314.17 apply as published. That edition governs permits filed through Aug. 16, 2026; permits filed on or after Aug. 17, 2026 fall under the 2026 NEC; see the 2026 NEC note on this drill for how the cited section fares there.
How Minnesota adopts the NECWhy the other choices are wrong
- A bathroom receptacle must be at least 3 ft away from the sink. It is the reverse: 210.52(D) requires at least one receptacle within 3 ft of the outside edge of each basin.
- The bare grounding conductor must be green insulated inside the box. Equipment grounding conductors may be bare, covered, or insulated (250.118 and 250.119); bare copper in NM cable is normal.
- Nothing. This installation is compliant. The conductors stop at the face of the box. 300.14 requires at least 6 in of free conductor and, for an opening under 8 in, at least 3 in beyond the opening.