PRELIMINARY ENGINEERING TOOL
Transformer full-load current calculator
Calculate primary and secondary current from transformer kVA and nominal voltages.
Inputs
Calculation steps
I₁ = 100000 / (√3 × 11000)
I₂ = 100000 / (√3 × 415)
Formula ID: TRANSFORMER_3PH_FULL_LOAD_V1
Assumptions and references
Nameplate apparent power is treated as available on both sides. This does not model losses, regulation, impedance, tap position or inrush.
UNDERSTAND THE TOOL
What this calculator does
Convert a transformer apparent-power rating into nominal full-load current on both sides for single-phase or balanced three-phase systems.
How to use it
- Choose the transformer phase arrangement.
- Enter the nameplate kVA rating.
- Enter primary and secondary nominal voltages.
- Review both current results and the excluded design checks.
Fields and meanings
- Rating
- Transformer apparent-power rating in kVA.
- Primary voltage
- Nominal supply-side voltage.
- Secondary voltage
- Nominal load-side voltage.
- Phase
- Select single phase or balanced three phase.
Review required. Inrush, impedance, regulation, losses, protection and fault levels require separate assessment.
Read the full explanation →