Transformer Calculator

Free online Transformer Calculator. Calculate primary and secondary winding full-load currents based on kVA rating.

⚡ Interactive Calculation Engine Active

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How to Use Transformer Calculator

  1. Enter the transformer rating in kVA.
  2. Select single-phase or three-phase winding systems.
  3. Input the primary and secondary voltage levels.
  4. Adjust the turns per volt constant to calculate winding turns.

Transformer Currents and Sizing Safety

Transformers step voltages up or down while transferring power. Due to energy conservation, the side with higher voltage carries a lower current, and vice versa. Knowing full-load currents is essential to size breakers and isolator cables.

Frequently Asked Questions

How is turns ratio related to voltages?
The turns ratio (Np / Ns) of a transformer is directly proportional to the primary and secondary voltage ratio (Vp / Vs) under ideal conditions.