Transformer Calculator

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Primary and secondary full-load currents from the kVA rating, and the turns ratio and secondary turns from the voltages

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Enter the values

What to work out

Phase

Rating

kVA

Primary voltage

Secondary voltage

Result

Primary full-load current

5.249A

Secondary full-load current

139.12A

Working

Formulas

Assumptions

An ideal transformer: losses and no-load current ignored.
For three phase use line voltages; the winding connection (Δ/Y) changes the phase current, not the line current.

Sources: Standard diploma electrical textbook relations (B. L. Theraja, Electrical Technology)

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