NEC ElectricalCode Illustrated

Electrical Code Illustrations

$2.99

Now with a live NEC Article 220 load calculator and plain-English code requirements for every chapter — the complete field reference for electricians. Illustrations of Electrical Code (NEC) — From Utility Service to Branch Circuits A visual reference library for electricians, electrical engineers, inspectors, and students — covering the National Electrical Code from the utility service entrance all the way to branch circuits and special systems. Browse 165 hand-picked illustrations organized into 11 categories: Distribution Systems — Site plans, ring bus diagrams, and voltage distribution systems Service Entrance — Overhead and underground service, utility pole connections, and clearance requirements Panel Layouts & Schedules — Residential and commercial panel diagrams and load schedules Wiring Diagrams & Floor Plans — Residential floor plans, schematic wiring diagrams, and rough-in illustrations Grounding & Bonding — Electrode systems, bonding diagrams, ground-fault return paths, and NEC Article 250 references Overcurrent & Motor Circuits — Motor branch circuit protection, conductor sizing, and fault current diagrams Load Calculations — Conductor sizing flowcharts, demand tables, and voltage drop formulas Low Voltage & Special Systems — NEC Article 725, CCTV, access control, intercom, and integrated LV systems Safety & Code Compliance — Inspection checklists, permit flowcharts, and building code references Fire Alarm Systems — Riser diagrams, wiring topologies, zone layouts, and sequence of operations Building Automation — BACnet/IP, BMAS overviews, HVAC control flowcharts, and ventilation diagrams Residential Load Calculator (NEC Article 220) Calculate service load the standard NEC method — general lighting, small appliance and laundry circuits, large appliances, HVAC, and optional loads all in one place. Results update live as you type, with automatic demand factor application, service size recommendation, and conductor sizing for the hot, neutral, and grounding electrode conductor. NEC Reference Requirements Plain-English summaries of key NEC requirements organized by chapter — from working space clearances and conductor terminations to GFCI protection, grounding, and equipment installation rules. Search by article number or topic to find what you need in the field, fast. Features: Swipe left and right to flip through illustrations within any category Pinch to zoom in for fine detail — pan while zoomed Double-tap to zoom in, double-tap again to reset Bookmark any illustration as a favorite for quick access Works on iPhone and iPad Full Dark Mode support A practical field and study companion for anyone working with the NEC.

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This update adds two new tools and 5 new illustrations. Residential Load Calculator — Enter your dwelling's square footage, appliances, and HVAC loads and get a live NEC Article 220 Standard Method calculation: demand-adjusted total load, recommended service size (100A–400A), and conductor sizing for the hot, neutral, and grounding electrode conductor. NEC Reference Requirements — Plain-English summaries of key code requirements across all 9 NEC chapters. Tap any chapter to expand its rules, or search by article number or topic keyword to find what you need instantly. Plus 5 new illustrations added to the Service Entrance, Panel Layouts, Wiring Diagrams, Load Calculations, and Low Voltage categories.

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    Provider
    • Yuhsiu Lai
    Size
    • 517.5 MB
    Category
    • Utilities
    Compatibility
    Requires iOS 16.0 or later.
    • iPhone
      Requires iOS 16.0 or later.
    • iPad
      Requires iPadOS 16.0 or later.
    Languages
    • English
    Age Rating
    4+
    Copyright
    • © 2026 iTech