Electrical Load Calculator

Free online Connected Load Calculator. Estimate maximum demand using NEC diversity factors for residential and industrial loads.

⚡ Interactive Calculation Engine Active

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How to Use Electrical Load Calculator

  1. Add appliances or custom loads to the calculator.
  2. Specify quantities and individual watt ratings for each appliance.
  3. Configure system voltage, phase, and power factor parameters.
  4. Check the total connected load versus max demand output.

Applying Diversity Factors to Electrical Design

Sizing an electrical service panels or generator for the full connected load is uneconomical. Electrical codes apply diversity factors (e.g. 60% for lighting, 50% for standard sockets) to estimate the realistic maximum demand, preventing oversized equipment.

Frequently Asked Questions

What is the difference between connected load and maximum demand?
Connected load is the sum of power ratings of all installed electrical appliances. Maximum demand is the actual peak load drawn at any given time, which is lower because not all appliances run concurrently (diversity factor).