New disposer under the kitchen sink
What's wrong here?
- The cord enters the disposer through a bare knockout with no cord connector or strain relief
- A disposer must be hard-wired; a cord-and-plug connection is not permitted
- The disposer receptacle has to be on the countertop backsplash, not inside the sink base
- Nothing. This installation is compliant
Show the answer and the code reference
The answer
The disposer cord passes through an open knockout in the housing with no cord connector, so there is no strain relief and nothing protects the cord from the sharp edge.
Correct choice: 1. The cord enters the disposer through a bare knockout with no cord connector or strain relief
Flexible cord must be connected so that tension is not transmitted to joints or terminals (400.14), and where it passes through a hole in an enclosure or cover it must be protected by a bushing or fitting (400.17). Here the jacket stops short of the housing and the individual conductors ride on a raw steel edge; every time the cabinet gets loaded or the cord gets yanked, the pull lands on the wire nuts inside the disposer and the insulation saws on the knockout. Disposer cord kits include a strain-relief connector for exactly this reason, and 110.3(B) requires following those instructions.
How to fix it
Install the listed cord connector (strain relief) in the knockout, pull the cord jacket through so it extends into the wiring compartment, tighten the connector on the jacket, and remake the connections. Keep the cord 18 to 36 in. long per 422.16(B)(1).
Code references
NEC 2023 400.14 — Pull at Joints and Terminals
Flexible cords and flexible cables shall be connected to devices and to fittings so that tension is not transmitted to joints or terminals. An informational note lists knotting the cord, winding with tape, and fittings designed for the purpose as methods.
Drills citing 400.14NEC 2023 400.17 — Protection from Damage
Flexible cords and flexible cables shall be protected by bushings or fittings where passing through holes in covers, outlet boxes, or similar enclosures.
Drills citing 400.17NEC 2023 422.16(B)(1) — Electrically Operated In-Sink Waste Disposers
A disposer may be cord-and-plug connected with a cord identified in the manufacturer's instructions, terminated in a grounding-type plug, 18 to 36 in. long, with the receptacle accessible and located to avoid physical damage to the cord.
Drills citing 422.16(B)(1)NEC 2023 110.3(B) — Installation and Use
Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.
Drills citing 110.3(B)
2026 NEC:same rule and number. No 2026 change to 400.14 (pull at joints and terminals) or 400.17 (bushings or fittings through enclosure openings) turned up in change summaries. Article 400 saw only minor 2026 edits, such as a new informational note at 400.1. 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 400.14, 400.17 and 422.16(B)(1) 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 disposer must be hard-wired; a cord-and-plug connection is not permitted. 422.16(B)(1) specifically permits a disposer to be cord-and-plug connected with a grounding-type plug and a cord 18 to 36 in. long, identified in the manufacturer's instructions.
- The disposer receptacle has to be on the countertop backsplash, not inside the sink base. 422.16(B)(1) only requires the receptacle to be accessible and located to avoid physical damage to the cord. The sink base is the normal location.
- Nothing. This installation is compliant. The cord passes through a sharp-edged knockout with no fitting, so pull on the cord goes straight to the terminals and the jacket can be cut (400.14, 400.17).