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📱 EPISODE 2 — Article 336 (Part 2 of 2)

Uses Not Permitted, Bending, Ampacity & Construction — Article 336 Complete!

SLIDE 1 — Uses NOT Permitted (336.12)
🚫 WHERE TC CABLE CANNOT GO

❌ Exposed to physical damage
❌ Outside a raceway or cable tray system — EXCEPT where 336.10(4), (7), (9), or (10) specifically permit it (messenger-supported outdoor, TC-ER exposed runs, TC-ER-JP dwellings, direct burial)
❌ Exposed to direct sunlight, UNLESS identified as sunlight resistant

SLIDE 2 — Bending Radius (336.24)
📐 DEPENDS ON SHIELDING AND SIZE

Without metal shielding:
🔹 ≤1 in. diameter → 4x the overall diameter
🔹 >1 in. to 2 in. diameter → 5x the overall diameter
🔹 >2 in. diameter → 6x the overall diameter

WITH metallic shielding: minimum bend radius = 12x the overall cable diameter — a much bigger jump due to the shielding material.

SLIDE 3 — Securing, Supporting & Ampacity
🛠️ SUPPORT METHODS (336.30)

Permitted: listed cable ties, staples, cable cleats, straps, hangers, or other approved means that won't damage the cable. TC fittings/connectors can also serve as support.

📊 AMPACITY (336.80)
🔹 14 AWG and larger, IN cable trays → per 392.80(A)
🔹 18–16 AWG, IN cable trays → per 402.5
🔹 Installed OUTSIDE cable trays (where permitted) → per 310.14

Three different ampacity references depending on conductor size AND installation location — pay close attention on the exam to WHICH scenario applies.

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

🔹 Sheath (336.100): NO metallic sheath/armor (as defined in 330.116) permitted under OR over the nonmetallic jacket — BUT metallic shields ARE permitted over conductor groups, under the outer jacket
🔹 Conductors (336.104): power/grounding conductors 16 AWG–1000 kcmil (copper/nickel/nickel-coated copper), 14 AWG–1000 kcmil (copper-clad aluminum), 12 AWG–1000 kcmil (aluminum). Control/signal min. 18 AWG copper / 16 AWG copper-clad aluminum
🔹 Jacket (336.116): flame-retardant, nonmetallic material
🔹 Marking (336.120): NO voltage marking allowed if the cable uses thermocouple extension wire

⚠️ Special notes: fire alarm conductors also follow 760.49; thermocouple circuit conductors can use thermocouple extension wire materials; 18/16 AWG Class 1 conductors also follow 724.49.

🔥 HAZARDOUS LOCATION VARIANT (336.126)
TC-ER-HL marked cable needs: environment-suitable nonmetallic jacket, essentially circular cross-section, and a continuous gas/vapor-tight jacket.

🎉 That's a wrap on Article 336 — Power and Control Tray Cable, Type TC!

🧠 FINAL EXAM QUESTION FOR ARTICLE 336

Q: Per 336.24, what is the minimum bending radius for Type TC cable WITH metallic shielding?

A) 6 times the overall diameter
B) 8 times the overall diameter
C) 10 times the overall diameter
D) 12 times the overall diameter

(Drop your final answer 👇)

Article 336 = DONE ✅ FOLLOW for more daily quick-hit NEC study notes ⚡ #JoshTheSparky #NEC2026 #ElectricianLife

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