Transformers
Transformer ratios, kVA, and turns calculations.
Calculators
Turns Ratio Calculator
Calculate a transformer's turns ratio from primary and secondary voltage (a = Vp ÷ Vs).
Transformer kVA Calculator
Calculate a transformer's kVA rating from voltage and current (kVA = V × I ÷ 1000).
Primary Current Calculator
Calculate a transformer's primary current from its kVA rating and primary voltage (Ip = (kVA × 1000) ÷ Vp).
Secondary Current Calculator
Calculate a transformer's secondary current from its kVA rating and secondary voltage (Is = (kVA × 1000) ÷ Vs).
Guides & Examples
Formula
Transformer Turns Ratio Formula
The transformer turns ratio formula, its variables, and how it relates primary and secondary voltage.
Example
Transformer Examples
Worked, step-by-step examples calculating turns ratio, transformer kVA, and primary and secondary current.
Guide
Understanding Transformers
How transformers step voltage up or down, what turns ratio and kVA rating mean, and how primary and secondary current relate.