Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

No Load Volts (V)

Required number input.

Full Load Volts (V)

Required number input.

Transformer voltage regulation from no-load and full-load secondary RMS voltage at the same primary supply. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Regulation Percent (%)

The resulting regulation percent returned as a number.

• Transformer ratios and losses depend on waveform, frequency, core material and flux, turns, winding resistance, leakage, magnetizing current, load power factor, temperature, insulation, and construction. Ideal turns-ratio equations do not establish regulation or thermal rating.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Transformer Voltage Regulation

  Calculate transformer voltage regulation as (no-load secondary voltage − full-load secondary voltage)/full-load voltage ×100. Use measurements at the same primary voltage and frequency.

• Transformer Copper Loss at Load

  Sum primary and secondary winding I²R losses using RMS currents and operating-temperature resistances. Additional windings and AC resistance effects are not included.

• Voltage Ratio

  Compute the transformer secondary voltage from the primary voltage and winding turns.