How far must the sheath of a nonmetallic cable assembly extend beyond the cable clamp inside the box?

The requirement for the sheath of a nonmetallic cable assembly to extend beyond the cable clamp inside an electrical box is specified in the National Electrical Code (NEC). The correct answer is that the sheath must extend a minimum of 1/4 inch beyond the cable clamp. This 1/4-inch extension ensures that the cable's insulation is adequately protected and that the conductors inside the cable are held securely within the box.

This requirement helps prevent damage to the cable insulation, which could lead to potential electrical hazards such as shorts or leaks. Additionally, this extension allows for proper assembly and reliability of the connections made inside the box. By ensuring that the sheath extends adequately, installers can maintain compliance with safety standards and protect the integrity of the electrical installation.