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Transformer Sizing Calculator

FLA both sides, 125% protection hints each side and standard primary OCPD. 3 inputs, 4 outputs with grouped results.

Inputs

Nameplate

Nameplate.

Windings

Primary volts.

Secondary volts.

Result

Primary FLA
Waiting for calculation.
Secondary FLA
Waiting for calculation.
Primary OCPD
Waiting for calculation.
Secondary OCPD
Waiting for calculation.
Screening calculation only. Verify against NEC articles cited on the page and the equipment nameplate; the authority having jurisdiction governs.

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Workspace

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