Free electrical load calculation tool for residential and commercial buildings. Calculate service entrance sizing, panel loads, demand factors, and ensure NEC Article 220 compliance. Calculating Circuits for Lights and Sockets in Commercial Fit-Out Projects: A Project Manager's Guide The management of a commercial fit-out involves many tasks, and one of the most important activities is ascertaining the number of electrical circuits required for lights and sockets. Essential for wire sizing and circuit protection. Updated against the current NEC, IEEE, and NEMA references. These tools cover the math working electricians, technicians, and engineers actually run on the job — sizing wire and conduit, picking transformers and. What is Electrical Load Calculation? 1.