Work out transformer kva instantly with clear inputs, formula shown and shareable results.
Transformer rating is in kVA, not kW, because the winding and core losses depend on current rather than useful power. Dividing the design load by power factor converts kW to kVA, then diversity and growth allowances set the design load before selecting the next standard rating up.
Transformer sizing
kVA = kW x diversity x (1 + growth) / power factor, then round up to a standard rating
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.
Heating is caused by current in the windings and flux in the core, neither of which cares about the load's phase angle. Only apparent power captures both.
Continuous full load leaves no margin for ambient temperature, harmonics or growth. Most designs target 70-85% of nameplate for the expected peak.