Commercial Electrical Designer
NEC Reference & Calculators
$2.99 · Designed for iPad. Not verified for macOS.
Version 2.0 adds a Project Checklist, Electrical Glossary, and What's New screen. The complete NEC reference for commercial electrical design — now with even more tools.
This app is a visual reference and calculation tool for electrical engineers, designers, electricians, and students working on commercial building projects.
Built around a real-world commercial strip mall, this app puts professional electrical illustrations, NEC code look-up, interactive calculators, step-by-step design calculation guides, a project checklist, and an electrical glossary in one place — offline, on iPhone and iPad.
BROWSE — ILLUSTRATED DRAWINGS
23 professional illustrations in 8 design categories:
Floor Plans & Key Plans — dimensioned tenant layouts and color-coded key plans
Electrical Plans — device plans with lighting, receptacles, switches, and panels
Wiring Layouts — branch circuit home runs and wiring path diagrams
Electrical Symbols & Legend — full device symbol reference
Panelboard Schedules — 200A, 208Y/120V, 3-phase schedules for Shops A, B, C, and the Building 2 main distribution panel
Panelboard Load Worksheets — conductor sizing tables with OCPD ratings and wire sizes per circuit
Feeder Load Calculation Worksheets — NEC Article 220 calculations for each tenant and the building main
Conductor & Conduit Sizing Steps — step-by-step sizing sheets for phase, neutral, and grounding conductors
Pinch to zoom up to 6× on any illustration. Swipe between images in the same category. Save any illustration to Favorites for fast retrieval.
NEC REFERENCE
Searchable, expandable code cards for the articles most relevant to commercial design: Article 210 (Branch Circuits), 215 (Feeders), 220 (Calculations), 230 (Services), 240 (Overcurrent Protection), 250 (Grounding and Bonding), 310 (Conductors), and 408 (Panelboards).
CALCULATORS
Ten interactive calculators covering the full commercial design workflow: Branch Circuit Load, Feeder Load, Voltage Drop, Wire Sizing, Conduit Fill, Panel Load Balance, Demand Factor, Short Circuit Current, Power Factor Correction, and Service Size.
DESIGN CALCULATIONS
Seven step-by-step calculation modules with NEC references, formulas, and worked examples: Branch Circuit Load Worksheet, Feeder Load Calculation, Phase Conductor Sizing, Neutral Conductor Sizing, Equipment Grounding Conductor, Conduit Fill & Trade Size, and Panelboard Load & Phase Balancing — including a full Building 2 Panel L1 worked example.
PROJECT CHECKLIST (NEW IN 1.1)
A phase-by-phase checklist covering the full commercial electrical project workflow — Pre-Design, Load Calculations, Conductor Sizing, Panelboard Design, Drawing Set, Permit & Approval, and Final Inspection. Each item includes the applicable NEC reference. Progress is tracked automatically and saved between sessions.
ELECTRICAL GLOSSARY (NEW IN 1.1)
55+ NEC and electrical engineering terms with plain-language definitions and code references — alphabetically indexed and fully searchable. Covers key terms including Ampacity, Branch Circuit, Continuous Load, Demand Factor, EGC, Feeder, FLA, GFCI, AFCI, OCPD, Power Factor, Service Entrance, Unit Load, Voltage Drop, and more.
FOR iPHONE AND iPAD
Fully responsive layout adapts to any screen size and orientation. All content is available offline — no subscription or account required.
Ideal for electrical engineering students, practicing engineers, electrical designers, contractors, and inspection professionals working with NEC-based commercial electrical systems.
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- This app hasn’t received enough ratings or reviews to display an overview.
Version 2.0 adds three new features:
Project Checklist — A phase-by-phase checklist covering the full commercial electrical design workflow, from Pre-Design through Final Inspection. Each item includes the applicable NEC code reference. Progress saves automatically between sessions.
Electrical Glossary — 55+ NEC and electrical engineering terms with plain-language definitions, NEC references, and alphabetical indexing. Fully searchable and available offline.
Phase Balancing Module — A new step-by-step Design Calculations guide for panelboard load calculation and phase balancing, based on the Building 2 Panel L1 worked example.
Also includes stability improvements and smoother gallery scrolling.
The developer, Yuhsiu Lai, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Yuhsiu Lai
- Size
- 44.1 MB
- Category
- Education
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 iTech Tools

