Fault Current Calculator vs NEC Load Calculator

Eaton's Bussmann Series FC2 Available Fault Current Calculator application is an innovative tool developed for contractors, engineers, electricians, and electrical inspectors. This tool can be used on the Bussmann website or out in the field on a mobile device for those needing a quick and simple way to determine available fault current. With this simple tool, users can: - Calculate available fault current on single and three-phase systems - Create and send a label via email for marking the available fault current on service equipment (NEC® 110.24) - Size fuses and conductors for service, feeder, and branch circuits. This application, calculations, and other information are intended to clearly present technical information that will determine the available fault current at specific points in an electrical system. Bussmann reserves the right, without notice, to change this application and/or discontinue/ limit its distribution and/or availability. Bussmann also reserves the right to change or update, without notice, any technical information contained in this application. The data and information presented in this application are believed to be accurate. However, any and all liability for the content, or any omissions from this application, including any inaccuracies, errors, or misstatements in such data, calculations or information, is expressly disclaimed. The application, calculations and other information are provided without warranty of any kind, either expressed or implied, but not limited to, the implied warranties of merchantability, or fitness for a particular purpose. Bussmann disclaims any liability for the use of this application, calculations or other information. The complete End-User License Agreement can be found at: https://faultcurrentcalculatorpro.bussmann.com/home/eula

NEC Load Calculator answers panel sizing, feeder, motor, branch circuit, and cable tray questions directly from the 2023 NEC — with the article citation and math shown for every result. Built for licensed electricians and contractors, not students. CALCULATION MODULES Residential Dwelling unit service sizing per NEC 220.40–220.55 and 220.82. Standard and optional methods. General lighting, small appliance and laundry circuits, fixed appliances, dryer, cooking equipment, HVAC, and service sizing with 230.79(C) minimums. Commercial Feeder and service load calculations per NEC 220.12, 220.44, 220.60, 430.24. Lighting, receptacles, motors, HVAC units, sign circuits, and demand factors. Supports 220/127V and 440/254V systems alongside standard US voltages, with a built-in reminder to verify against NOM-001-SEDE where applicable. Branch Circuit Conductor and OCPD sizing per NEC 210.19, 310.12, 310.15(B)(1)(a). Continuous load handling, conduit fill derating, ambient temperature correction. Covers 120V through 480V circuits, including 127V, 220V, 254V, and 440V. Motor Conductor, overload, and OCPD sizing per NEC 430.22, 430.32, 430.52. Full motor table lookups by horsepower, voltage, and phase. Panel Schedule Circuit-by-circuit panel editor with phase balance, loading percentage, and imbalance calculations per NEC 220.40 and 220.87. Cable Tray Tray fill and ampacity derating per NEC 392.22(A) and 392.80(A). Ventilated trough and solid-bottom tray types, small-cable fill-area limits, and the 90% width rule for large-cable diameter sums. RESULTS SHOW THE CALCULATION Every result includes the NEC article reference, the demand factor table used, and the step-by-step math — not just a final number. Built to be checked against the code book. PANEL LAYOUT Generate a panel layout directly from a load calculation: circuit numbers, breaker sizes, two-pole spans, and spare spaces, arranged the way a real panelboard is wired. Hand off into the full Panel Schedule editor to adjust circuit labels, phase assignment, or breaker sizes. PDF EXPORT Export any result as a PDF report for permit submission, job documentation, or client records.