Quick Hits

Episode 3: Construction Methods — Cables, Conduits & Busways (604.100(A)(1)–(5))

SLIDE 1(HOOK / COVER) ⚡ NEC Quick Hit: Prefab Construction & Conductor Sizing (Part 3) ⚡ 

What wire sizes are permitted inside manufactured wiring assemblies? Can you use FMC or modular busways? Let's break down Section 604.100 construction standards! 👇

SLIDE 2 (CABLES & CONDUITS) Permitted Wiring Methods:

• Cables: Listed Type AC or MC containing nominal 600V, 8 AWG to 12 AWG copper (or 6–10 AWG Al/Cu-Clad).

• Conduits: FMC, LFMC, LFNC, and EMT containing 8–12 AWG conductors with a matching equipment grounding conductor.

• Lighting Tap Exception: Luminaire tap conductors up to 1.8 m (6 ft) long are permitted down to 18 AWG.

SLIDE 3 (BUSWAYS & PREWIRED RACEWAYS) Plug-in Power & Surface Modularity:

• Plug-In Busways: Listed continuous plug-in busways containing factory-mounted copper/aluminum conductors, rated 20, 30, or 40 amperes.

• Prewired Surface Raceways: Prewired modular surface-mounted raceways listed and rated nominal 600V, 20 amperes.

SLIDE 4 (WRAP-UP) 💡 Apprentice Pro-Tip: 

The 18 AWG tap conductor exception makes modular lighting whips possible, but those taps must be dedicated strictly to connecting a single luminaire!

💬 Save this post for your next modular power distribution spec check! 🔗 

More code breakdowns and study tools at www.JoshTheSparky.com

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