Kopperfield vs Electrical Load Calc NEC

Save time and money. Get ready for permits and projects with faster and easier design tools from Kopperfield, including load calcs, line diagrams, panel schedules, and more. Once logged into your Kopperfield account, you'll enjoy our: * Load calculator: Easy-to-use interface pre-loaded with common appliances and their standard output values from the National Electrical Code. Add information on the property and your calculation will automatically update. Supports both commercial and residential calculations, as well as the Standard (NEC Article 220 Part III), Optional (NEC Article 220 Part IV), and 2026 Standard (NEC Article 120 Part III) methods. * Single line diagram tool: Contains dozens of common templates and electrical symbols to make it easy to generate new diagrams and share them with your team. View diagrams from any device and create new templates on tablet or desktop for your whole team to use. * Panel schedules: Includes tools to complete panel schedules and create labels for electrical panels. Drag-and-drop interface makes it easy to arrange and customize circuits for both split-phase and three-phase projects. * NEC chatbot: Custom chatbot with advanced search capabilities to quickly reference specific sections of the 2017, 2020, or 2023 National Electrical Code. Includes the following features: * Fast PDF outputs: instantly generate a downloadable, one-page PDF report of your load calc, line diagram, or panel schedule to share with inspectors and customers * Smart property data: enter the property address and we’ll pull in the square footage for any customer project or electrical load calculation * AI panel photo processing: upload a photo of an electrical panel to automatically add items to your load calculation or panel schedule * Team dashboard: store your team's projects and documents in one place for easier management, access, and review *Single and three phase options: use a variety of nominal voltages for residential and commercial building types, including: 120/240V, 120/208V, 120/240V, 208Y/120V 3Ø, 240V 3Ø Delta, 240V 3Ø Hi-leg Delta, 347V 3Ø Delta, 480Y/277V 3Ø, 480V 3Ø Delta, 600Y/347Y 3Ø, 600V 3Ø Delta. * Standard scenarios: generate load calcs for scenarios including single family homes (standard and optional methods), multi dwelling units (i.e., duplex, triplex, quad), 120/208v (three-phase power) dwellings, accessory dwelling units and additions, commercial occupancy types, and heat pumps * Common appliance defaults: choose from a pre-loaded list of common appliances and standard output values that you can adjust for every load calculation * EV charger inputs: include EV charger values to any load calculation, essential for modern homes

NEC residential electrical load calculator for electricians, contractors, and electrical engineers. Size electrical services with confidence using the NEC 220.82 Optional Method and updated NEC 2026 Article 120 demand factors. Works 100% offline on the job site. Enter dwelling square footage, pick appliances from presets, and get a permit-ready service-size recommendation in seconds - with a full step-by-step breakdown and NEC article references on every line. Switch between NEC 2023 and NEC 2026 instantly to see how the new rules change your load. LOAD CALCULATION FEATURES: - NEC 220.82 Optional Method for dwelling units - NEC 2026 Article 120 support (load calc sections renumbered 220.x to 120.x) - Toggle between NEC 2023 and NEC 2026 in one tap - Step-by-step breakdown with NEC article references per line - Heating and A/C per 220.82(C): A/C and heat pump compressor at 100%, supplemental heat at 65%, electric space heating at 65% (under 4 units) or 40% (4 or more units) - EVSE per edition: 2023 as general load per 220.57 and 220.82(B) with 7,200 VA minimum; 2026 at 100% per 120.82(D) - Service size from standard ratings: 100A, 125A, 150A, 200A, 225A, 300A, 400A, 600A - PASS/FAIL check against existing panel capacity - 29 common appliance presets with VA ratings - Custom appliance entry for any load - General lighting auto-calculated from square footage per 220.41 - Small appliance and laundry circuits added per 220.52 - HVAC non-coincident load handling (heating vs cooling) - EV charger support (Level 2: 32A, 40A, 48A) APPLIANCE PRESETS INCLUDED: - Electric range and oven (8,000-16,000 VA) - Clothes dryer (5,000-5,500 VA) - Water heater (4,500 VA) - Heat pump (2-5 ton) and central AC (2-5 ton) - Supplemental heat strips (5 kW, 10 kW) for heat pump systems - EV charger Level 2 (7,680-11,520 VA) - Dishwasher, disposal, microwave - Pool pump, hot tub, well pump - And more - or enter custom VA values PRO FEATURES (one-time purchase): - No ads - clean interface for professionals - Save calculation history by job or address - Export permit-ready PDF with full load breakdown - Dark theme support NEC 2026 UPDATES COVERED: - General lighting reduced to 2 VA/sq ft (was 3 VA/sq ft) - First tier demand reduced to 8,000 VA (was 10,000 VA) - EV chargers at 100% demand factor per 120.82(D) - Article 220 relocated to Article 120 (220.82 is now 120.82) HOW IT WORKS: 1. Enter dwelling square footage 2. Select NEC edition (2023 or 2026) 3. Add appliances from presets or custom entry 4. See total demand in amps with NEC article references 5. Get recommended service size instantly NEC ARTICLE REFERENCES: Every calculation line shows the exact NEC article reference (for example "NEC 220.82(B)" or "NEC 2026 120.82(D)"). Verify every step against the official NEC code book, build trust with inspectors, and prep for the electrical exam. PERFECT FOR: - Licensed electricians sizing residential services daily - Electrical apprentices studying for journeyman exams - Electrical contractors bidding residential and light commercial jobs - Electrical engineers and designers - Panel upgrade assessments - EV charger installation planning - New construction load calculations - Permit applications and plan review OFFLINE AND PRIVACY: - Works 100% offline - no internet needed on the job site - No account required - No data collection - your calculations stay on your device - Encrypted local storage for saved jobs Simplify residential load calculations on the job site.