Module 3 — Wiring & Protection

Articles 210 • 215 • 240 • 250

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Use the left TOC to jump to 210, 215, 240, 250. Verify values in your adopted edition.

Learning Objectives

Identify branch-circuit ratings and required circuits (Art. 210).
Size feeders and select overcurrent devices (Art. 215 & 240).
Explain grounding and bonding fundamentals (Art. 250).

Core Concepts

Topic	Focus
210 — Branch Circuits	Ratings, receptacle requirements, GFCI/AFCI scopes by area.
215 — Feeders	Sizing/equipment protection, tap concepts, conductor temp ratings.
240 — OCPD	Protection of conductors; devices vs. equipment ratings; selective coordination basics.
250 — Grounding & Bonding	Grounding electrode system, EGC sizing, bonding jumpers, continuity.

Field tip: Start with calculated load, then select conductor & OCPD together; confirm temperature columns and any derating/adjustment before finalizing.

Navigation Tips

Find required receptacles in 210 (kitchens, laundry, bathrooms) then check GFCI/AFCI scopes.
Use 215 for feeder sizing after you finish load calcs in Article 220 (preview for Mod 8).
Confirm conductor ampacity in 310 and loop back to 240 for OCPD matching.
Always finish with 250 to verify grounding/bonding specifics (EGC sizing tables, jumpers).

Tool — Voltage Drop Estimator

For design guidance only. Verify ampacity/voltage drop per your adopted NEC and AHJ amendments.

🔎 Practice Tool: Codebook Navigation

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