Cable Trays (392), Busways (368), Wireways (376), Surface and Strut Raceways (384/386/388) and Flexible Cords (400)
The PSI outline names "Raceways and Cable Trays" and "Cables and Cords" under Wiring Methods & Materials (10 Journeyman / 7 Master / 10 Residential items). Lessons 05-02 and 05-03 covered the conduit and tubing articles; this lesson closes the gap with the *other* raceway and support systems the exam reaches for — cable tray (392), busway (368), wireway (376), strut and surface raceways (384/386/388) — and Article 400 flexible cords. Everything below was read from the 2026 text.
NFPA 70 National Electrical Code, 2026 edition · Reviewed 2026-09-19
The PSI outline names "Raceways and Cable Trays" and "Cables and Cords" under Wiring Methods & Materials (10 Journeyman / 7 Master / 10 Residential items). Lessons 05-02 and 05-03 covered the conduit and tubing articles; this lesson closes the gap with the other raceway and support systems the exam reaches for — cable tray (392), busway (368), wireway (376), strut and surface raceways (384/386/388) — and Article 400 flexible cords. Everything below was read from the 2026 text.
1. Cable trays — Article 392 (a support system, not a raceway)
What it is. 392.10: cable tray is permitted as a support system for wiring methods containing service conductors, feeders, branch circuits, communications, control and signaling circuits. Ladder, ventilated trough, ventilated channel, solid bottom and similar structures (392.1). Not limited to industrial establishments. Where exposed to direct sun, insulated conductors and jacketed cables shall be identified as sunlight resistant.
What goes in it. 392.10(A) lists 30 permitted wiring methods — cables (AC, MC, MI, TC, ITC, PLTC, NM/NMC/NMS, SE/USE, UF, fire alarm, communications, optical fiber, Class 2/3/4) and raceways (EMT, ENT, IMC, RMC, PVC, RTRC, FMC, FMT, LFMC, LFNC). Single-conductor cables and single insulated conductors are permitted only in industrial establishments where qualified persons service the system (392.10(B)(1)): they must be 1/0 AWG or larger, listed and marked on the surface for use in cable trays; where 1/0 through 4/0 AWG single conductors are in ladder tray, the maximum rung spacing is 9 in. (225 mm); welding cables per 630 Part IV; single conductors used as EGCs may be insulated, covered or bare, 4 AWG or larger. Medium-voltage single/multiconductor cables are Type MV. 392.12: not in hoistways or where subject to severe physical damage.
Installing the tray — 392.18.
- (A) a complete system; field bends/modifications keep electrical continuity and support; mechanically discontinuous segments permitted between tray runs and at equipment.
- (B) each run completed before the cables are installed. (C)
This is where the public part ends.
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