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Secondary Current Calculator

Calculate a transformer's secondary current from its kVA rating and secondary voltage (Is = (kVA × 1000) ÷ Vs).

Formula

Is = (kVA × 1000) ÷ Vs

Is
Secondary current, in amps
kVA
Transformer rating, in kilovolt-amps
Vs
Secondary voltage, in volts

What this calculator does

Calculates the current available on a transformer's secondary winding from its kVA rating.

Use cases

  • Size secondary-side conductors and protection for a transformer
  • Check a transformer's available secondary current for a planned load
  • Verify a measured secondary current against the expected calculation

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