Transformer Sizing Calculator
Enter your connected load and power factor — get the required kVA, the nearest standard transformer size, and the resulting full-load current.
Please note: General guidance only — verify against the current standard before relying on this result. Not a substitute for a licensed electrical design.
Transformer sizing
No allowance for future growth or diversity — add your own margin.
Recommended transformer size
— kVA
Rough sizing only — a proper transformer selection accounts for load growth, diversity, inrush and voltage regulation, and must be confirmed by a licensed designer.
Export this result as a PDF
A clean, branded PDF of your inputs and result — handy for records or sending on.
Adding three-phase equipment or a bigger connection? That's usually aswitchboard upgradejob too — worth doing together.
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