Electrical Codes & Standards Summary

Electrical Codes and Standards

Code vs. Standard

• Code: Tells you what to do (e.g., provide a fire alarm system).
• Standard: Tells you how to do it (e.g., system type, function, components, placement).

Organizations and Codes

• International Code Council (ICC): Publishes various codes like IMC, IECC, IBC, IFC, IPC, and others.
• NFPA (National Fire Protection Association): Develops codes and standards.
  • NFPA 1: Fire Code
  • NFPA 70: National Electrical Code (NEC)
  • NFPA 72: National Fire Alarm and Signaling Code
  • NFPA 101: Life Safety Code
  • NFPA 5000: Building Construction and Safety Code

Specialty Codes and Standards

• Locally adopted codes (e.g., California Building Code).
• IgCC (International Green Construction Code).
• ADA Standards (for Accessible Design).
• ANSI/ASHRAE/ICC/USGBC/IES 189.1-2020: Standard for High-Performance Green Buildings.

Purpose of Codes

• Define minimum standards and requirements.
• Primarily for SAFETY.
• Sometimes include energy savings (e.g., IECC).
• Typically not performance-based.

National Electric Code (NEC)

• NFPA 70.
• Focuses on safety.
• Paired with NFPA 70E (installer and maintenance safety).
• Updated every 3 years; 2023 is the latest edition.
• Adopted or amended by jurisdictions/municipalities.

Energy Codes/Standards

• IECC (International Energy Conservation Code): Most common.
• ASHRAE 90.1: Used for LEED.
• Title 24: California Energy Code.

Common Building Voltages

• Higher voltage = lower amps (for same power).
• Lower amps = smaller wires and equipment.
• Power (W or VA) remains constant regardless of voltage.

Building Utility Transformers

• Step down voltage to the level desired by the building.
• Typically pole or ground mounted.

Voltage Options and Terminology

• Line Conductor: AKA Hot conductor, phase conductor.
• Neutral Conductor: AKA Grounded conductor.
• Ground Conductor: AKA Equipment Ground, Grounding Conductor.

Voltage Configurations

• 240/120V – 1 phase, 3-wire

  • Typical for residential, small commercial, and family farms.
  • $S=IV$
  • @120V, $I=(VA/120)$
  • @240V, $I=(VA/240)$

• 208/120V – 3 phase, 4-wire

  • “Wye” configuration (common point).
  • Common for commercial projects.
  • @120V, $I=(VA/120)$
  • @208V, 1-phase, $I=(VA/208)$
  • @208V, 3-phase, $I=(VA/(208_sqrt{3}))$

• 480/277V – 3 phase, 4-wire

  • Same as 208/120V but with different voltage/turns ratio.
  • Benefit: 480V allows for lower current than 208V for the same power.
  • @277V, $I=(VA/277)$
  • @480V, 1-phase, $I=(VA/480)$
  • @480V, 3-phase, $I=(VA/(480\sqrt{3}))$

• 240/120V – 3 phase, 4-wire

  • Occasionally used in small commercial settings.
  • "Delta" configuration (end-to-end connection).
  • Neutral tap between phases creates a high leg (wild leg, red leg, stinger leg).
  • High leg must be clearly marked.