NM Cable 334.40(B)

Code Q&A: NM Cable and Insulated Devices

Q. When does the Code allow Type NM cable to be spliced using NM cable interconnection devices?

See the answer below.









This answer is based on the 2017 NEC.

A. A box or conduit body isn’t required where a listed nonmetallic-sheathed cable interconnector device is used for any exposed cable wiring or for concealed cable wiring in existing buildings in accordance with Sec. 300.15(H) [334.40].

Per UL (QAAV), interconnection devices have been investigated for equivalency to Type NM cable in insulation and temperature rise, and for capability to withstand fault currents, vibration, and mechanical shock that may occur during transport. The interconnects are intended for use with 14 AWG and 12 AWG solid or stranded copper conductors.

These materials are provided to us by Mike Holt Enterprises in Leesburg, Fla. To view Code training materials offered by the company, visit www.mikeholt.com/code.

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