Electrical Load / Breaker Sizing Calculator
Frequently asked
How do you calculate main breaker size?
Find full load current by dividing the diversity-adjusted load by voltage and power factor, then select the next standard breaker size. This calculator does that for single and three phase supplies.
What is diversity factor in electrical load?
Diversity factor accounts for the fact that not all appliances run at full load simultaneously. A factor of 0.8 is typical for residential. This calculator applies it to reduce the connected load.
What cable size do I need for 5 kW single phase?
For 5 kW at 230V with 0.95 power factor, the current is about 22A, so a 4 sqmm copper cable is sufficient. This calculator gives exact cross-section based on your inputs.
Which related calculators pair well with the Load / Breaker Sizing Calculator?
People sizing electrical systems often also need Wiring Points Calculator to estimate complete wiring. Each is free and quotation-ready.