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📱 EPISODE 2 — Article 370 (Part 2 of 2)

Conductor Supports, Fittings & Grounding — Article 370 Complete!

SLIDE 1 — Conductor Supports (370.30(B))
📏 SPACING RULES FOR THE CONDUCTORS THEMSELVES

Insulated conductors supported on blocks or identified mounting means:
🔹 Horizontal runs → supported at intervals not greater than 3 ft (900mm)
🔹 Vertical runs → supported at intervals not greater than 1½ ft (450mm)

Spacing between supported conductors: not less than one conductor diameter at support points — this controlled spacing is central to how cablebus dissipates heat via free air circulation.

SLIDE 2 — Fittings (370.42)
🔧 WHAT A COMPLETE CABLEBUS SYSTEM NEEDS

Fittings required for:
1️⃣ Changes in horizontal or vertical direction
2️⃣ Terminations at connected apparatus/equipment or their enclosures
3️⃣ Additional physical protection (guards) where subject to severe physical damage

SLIDE 3 — Grounding (370.60)
🌎 CABLEBUS FRAMEWORK CAN SERVE AS THE EGC

The cablebus FRAMEWORK, where bonded, CAN be used as the equipment grounding conductor for branch circuits and feeders — recognized under 250.118(A)(12).

Overall grounding/bonding follows Article 250 Parts V and VI, EXCLUDING 250.86 Exception No. 2.

📌 Similar to cable tray — the framework's EGC performance is a specific classification/testing program, not a full product listing.

SLIDE 4 — Ampacity & Marking + Final Exam Question
📊 AMPACITY (370.80)

🔹 0–2000V → per 310.17 and 310.19 (free air tables)
🔹 2001–35,000V → per Table 315.60(C)(3) and (C)(4)

🏷️ MARKING (370.120)
Nameplates: required at EACH terminating end — manufacturer name/designation, max conductor diameter, number, voltage rating, ampacity — visible after installation.
Identification: each section/fitting marked per manufacturer's installation instructions.

🎉 That's a wrap on Article 370 — Cablebus!

🧠 FINAL EXAM QUESTION FOR ARTICLE 370

Q: Per 370.60(1), what part of a cablebus system, where bonded, can be used as the equipment grounding conductor for branch circuits and feeders?

A) The insulated conductors themselves
B) The cablebus framework
C) A separate wire-type EGC only
D) The ventilated top cover only

(Drop your final answer 👇)

Article 370 = DONE ✅ FOLLOW for more daily quick-hit NEC study notes ⚡ #JoshTheSparky #NEC2026 #ElectricianLife

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