Subpanel Load Calculator
Use this subpanel load workflow for early load screening when connected VA, demand factor, voltage, phase, subpanel rating, and target spare capacity are already known.
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Dwelling load, panel load, service size, and NEC 220 demand workflows.
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Service Upgrade Calculator
Use this service upgrade workflow for early planning when a calculated demand, new load, service rating, and desired headroom target are already known.
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Heat Pump Electrical Load Calculator
Use this heat pump load workflow for early panel-load screening when nameplate MCA and auxiliary heat kW are already known.
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EV Charger Load Calculator
Use this EV charger load workflow to screen the load impact of one or more EVSE units against an entered existing load and panel rating.
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Dryer Load Calculator
Use this dryer load workflow for early load planning when dryer nameplate ratings and a demand factor basis are already known.
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Appliance Load Calculator
Use this appliance load workflow for preliminary row-by-row household appliance load arithmetic when appliance VA, quantity, demand factors, continuous multipliers, voltage, phase, and a comparison ampere value are known.
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Demand Factor Estimate (NEC 220 Context)
Use user-defined load blocks and demand-factor percentages to create a transparent U.S. English preliminary estimate. NEC 220 is retained as legacy and topical search context; current NEC load-calculation numbering, including Article 120/220 context, must be verified against the adopted edition. This calculator does not reproduce NEC tables, dwelling-unit rules, or any adopted code calculation.
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Residential Load Calculator
Enter the service voltage and four preliminary load estimates to calculate connected load, demand from the entered factor, current at the entered voltage, and diversity allowance. This transparent U.S. English model does not reproduce NEC demand rules or determine a compliant service size.
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Electrical Service Size Calculator
Use service voltage, phase count, a user-supplied real-power demand basis, power factor, and a target utilization percentage to create a transparent U.S. English preliminary service-size estimate. This calculator does not perform an NEC service calculation, service sizing, or code-compliant service-rating selection.
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Electrical Panel Load Calculator
Add three circuit load-current estimates to create a transparent preliminary estimate using the entered panel voltage, phase count, panel nameplate rating, and target reserve percentage.
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