Quick Hits

📱 EPISODE 2 — Article 338 (Part 2 of 2)

Uses Not Permitted, Bending & Construction — Article 338 Complete!

SLIDE 1 — Type SE Uses NOT Permitted (338.12(A))
🚫 WHERE TYPE SE CANNOT GO

❌ Subject to physical damage, UNLESS protected per 230.50(B)
❌ Underground — WITH OR WITHOUT a raceway (that's what USE is for!)
❌ Exterior branch circuit/feeder wiring UNLESS it complies with Article 225 Part I AND is supported per 334.30, OR used as messenger-supported wiring per Article 396 Part II

📌 Key exam trap: SE cable is NEVER allowed underground, even inside a raceway. That job belongs to USE.

SLIDE 2 — Type USE Uses NOT Permitted (338.12(B))
🚫 WHERE TYPE USE CANNOT GO

❌ Interior wiring — NOT its job
❌ Aboveground installations — EXCEPT where USE emerges from the ground and terminates in an outdoor enclosure, protected per 300.7(D)
❌ As aerial cable — UNLESS it's a multiconductor cable identified for aboveground use, installed as messenger-supported wiring per 225.10 and Article 396 Part II

The SE/USE split is really about environment: SE = above ground and sunlight-exposed conductors; USE = below ground, direct burial territory.

SLIDE 3 — Bending Radius (338.24)
📐 SAME FORMULA AS NM CABLE

Minimum bend radius = 5x the cable diameter. For FLAT cables: use the MINOR diameter dimension when bending on the flat side; use the MAJOR diameter for all other bends.

Same rule you saw back in Article 334 (NM/NMC) — consistent logic across nonmetallic-jacketed cable types.

SLIDE 4 — Construction Specs + Final Exam Question
🏗️ CONSTRUCTION SPECIFICATIONS

🔹 Assemblies (338.100(A)): cabled ("plexed" — twisted together) assemblies of multiple single-conductor USE conductors ARE permitted for direct burial — but ALL conductors must be insulated in that assembly
🔹 Uninsulated conductor (338.100(B)): SE or USE cable with an overall covering containing 2+ conductors CAN have ONE conductor uninsulated (typically the grounded/neutral conductor)
🔹 Marking (338.120): marked per 310.8. If the NEUTRAL conductor is SMALLER than the ungrounded conductors, that MUST be marked on the cable — a critical detail for field verification of reduced-neutral service cables.

🎉 That's a wrap on Article 338 — Service-Entrance Cable, Types SE and USE!

🧠 FINAL EXAM QUESTION FOR ARTICLE 338

Q: Per 338.12(A)(2), Type SE cable is prohibited from being installed underground under what condition?

A) Only if installed without a raceway
B) Under NO condition — with or without a raceway, underground use is not permitted
C) Only if the conductors are uninsulated
D) SE cable is always permitted underground if in PVC conduit

(Drop your final answer 👇)

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