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๐Ÿ“˜ NEC Chapter 2 Breakdown: Wiring & Protection Essentials

A guide to how power safely flows from service to device.

๐Ÿ”น Article 200 โ€“ Grounded Conductor ID

  • Neutrals (#6 and smaller): Must be white, gray, or striped.

  • Larger than #6? You can tape or mark it at terminations.

  • ๐Ÿ’ก Why it matters: Prevents misidentifying a neutral as a hot.

๐Ÿ”น Article 210 โ€“ Branch Circuits

  • Covers receptacle spacing, GFCI/AFCI locations, and circuit sizing.

  • ๐Ÿ’ก On site: Know your kitchen, bathroom, and exterior outlet rules cold.

๐Ÿ”น Article 215 โ€“ Feeders

  • Feeders go from the main panel to subpanels.

  • Watch for ampacity, length derates, and disconnects.

๐Ÿ”น Article 220 โ€“ Load Calcs

  • How to calculate service, feeder, and branch loads.

  • Required for panel sizing and avoiding overloading.

๐Ÿ”น Article 225 โ€“ Outside Feeders

  • For feeders run outside but not part of the service.

  • Think conduits on rooftops, or shed panels.

๐Ÿ”น Article 230 โ€“ Services

  • Where utility power enters the building.

  • Service entrance conductors, main disconnects, clearances.

๐Ÿ”น Article 240 โ€“ Overcurrent Protection

  • Covers breaker and fuse sizing.

  • Key for tap rules, conductor protection, and short-circuit safety.

๐Ÿ”น Article 250 โ€“ Grounding & Bonding

  • Probably the most cited article in the field.

  • Think: ground rods, equipment bonding, water pipe grounding, isolated grounds.

โœ… Why It Matters to You

If itโ€™s wired, it better be protected.
If itโ€™s metal, it better be grounded.
Chapter 2 makes sure both happen.

โ“ Quick Code Check

Choose the correct answer:

โ“ Question:
Youโ€™re installing a sub panel 100โ€™ away from the main. What do you check first?
A) Conduit fill
B) Voltage drop & conductor size
C) Lighting layout
D) Exit sign spacing

Answer below ๐Ÿ‘‡

๐Ÿง  Think it through โ€“ this conductor isnโ€™t for carrying fault current, but to equalize voltage potential across all metal parts in and around the pool.

โœ… Answer: B) Voltage drop & conductor size (Articles 215 & 220 apply)

๐Ÿ“˜ Reference:
NEC 215.2(A)(1) & 220.61 โ€“ These sections address feeder conductor sizing and load calculations, which are essential when installing sub-panels, especially at long distances where voltage drop becomes a key concern.

๐Ÿ”Ž Next Issue Preview:

Coming up: โ€œThe 5 Things a Field PM Should Track Daily (But Often Doesnโ€™t)โ€