Buck-Boost Transformer Calculator
Use this buck-boost transformer workflow for early voltage-change kVA screening when supply voltage, target voltage, load current, phase, and sizing multiplier are known.
- Voltage change
- V
- Buck/boost mode
- Load kVA
- kVA
- Buck-boost winding kVA
- kVA
- Required buck-boost kVA
- kVA
Calculation details
- Sizing multiplier used
- %
- Calculation basis
- Selection boundary
Recent results
Formulas
- Voltage change = target voltage - supply voltage
- Load kVA = load current x target voltage x phase multiplier / 1000
- Buck-boost winding kVA = load current x absolute voltage change x phase multiplier / 1000
- Required buck-boost kVA = buck-boost winding kVA x sizing multiplier percent / 100
Use this calculator
Estimate voltage change, buck or boost mode, load kVA, buck-boost winding kVA, and required kVA from entered voltage, current, phase, and sizing multiplier.
Read the result
Review the calculated values with their displayed units and assumptions. The result is a planning aid for the stated inputs, not a final equipment or installation decision.
Check before final work
This buck-boost transformer estimate is winding-kVA arithmetic only. It does not provide wiring diagrams, manufacturer catalog selection, grounding, protection, listing, or code compliance.
FAQs
Does this show the transformer wiring?
No. It estimates winding kVA only. Wiring and catalog selection must come from manufacturer instructions.
Why use voltage change instead of target voltage?
Buck-boost winding kVA is tied to the voltage being added or subtracted, while load kVA uses the load voltage.
Can this select a transformer?
No. Final transformer selection requires manufacturer, protection, grounding, listing, and installation review.