The quantitative backbone of every safe, compliant and efficient electrical system — every number code-referenced, auditable and permit-ready.
We perform step-by-step electrical load calculations strictly to NEC Article 220 — calculating general lighting loads, receptacle loads, branch-circuit loads, feeder loads and service entrance loads. We correctly apply demand factors and diversity factors so every panel, feeder and service is properly sized and the permit calculation package is accurate and defensible.
Panel sizing starts with an accurate NEC Article 220 load calculation to determine total connected and demand load. We then select the correct main breaker ampacity, bus rating, short-circuit current rating (SCCR), and number of spaces — and verify the panel is rated for the available fault current from the upstream source, per NEC 110.9 and NFPA 70E.
An arc-flash study calculates the incident energy at each piece of electrical equipment to determine the required Personal Protective Equipment (PPE) category for workers. We perform arc-flash analysis to NFPA 70E / IEEE 1584, produce arc-flash hazard labels with incident energy values and working distances, and integrate the results into our Revit BIM models.
A demand factor is the ratio of maximum demand to total connected load — it accounts for the fact that not all loads operate simultaneously at full capacity. NEC Article 220 specifies permitted demand factors for lighting, receptacles and specific equipment. Applying them correctly reduces the calculated load, which can significantly reduce the required service and feeder size and save on equipment costs.
Voltage drop calculations verify that conductor sizes are adequate so that voltage at the end of a run stays within code limits (NEC recommends a maximum 3% for branch circuits and 5% total from the service). Excessive voltage drop causes equipment to run hot, motors to draw more current, and lighting to flicker — all of which shorten equipment life and create code violations.
Generator sizing requires calculating the total connected load of all loads the generator must serve — including demand factors, motor starting kVA (which can be 6× running kW during startup), harmonic loading from variable frequency drives, and any required code reserves. We produce a complete generator sizing calculation to NFPA 110 and NEC Article 700/701/702, including load sequencing analysis.
Conductor sizing combines the NEC 310 ampacity tables with the correct temperature-rating column, ambient temperature correction and conductor-bundling adjustment factors — then verifies the result against voltage drop and terminal ratings. Conduit fill is checked to NEC Chapter 9 tables so every raceway stays within the permitted fill percentage and pulls remain practical in the field.
Yes. Every calculation we produce is rigorous, fully auditable and directly referenced to the applicable code section — NEC, NFPA 70E, NFPA 110, IECC or ASHRAE 90.1 as applicable. Our calculation packages include a cover sheet, code edition, assumptions log and results summary formatted for direct submission with the permit application.
EV charger load calculations follow NEC Article 220 for service and feeder sizing — with EVSE (Electric Vehicle Supply Equipment) circuits calculated at 125% of the continuous load per NEC 210.19. For commercial sites with multiple Level 2 or DC fast chargers, we design the Electric Vehicle Energy Management System (EVEMS) per NEC 625.42, which allows intelligent load sharing across all EV stations so the existing main service is maximized without costly utility upsizes. We also size the conduit, conductors and dedicated panels and coordinate meter placement with the local utility.
Yes. We size solar PV systems to NEC Article 690 — string sizing, DC/AC conductor sizing, rapid shutdown and interconnection analysis to NEC 705 — and Battery Energy Storage Systems (BESS) to NEC Article 706, determining required capacity (kWh) and power rating (kW) for peak-shaving, backup duration or renewable storage targets, with utility interconnection coordination included.
Every calculation auditable, referenced and ready for permit review.
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