Buck Boost Electronic Calculator, Calculates proper Square D Transformers to use when doing small changes in voltage: 5%, 6.6%, 10%, 13.3%, 20%, and 26.6%
  • Step One: Single Phase or Three Phase Application
    IF Three Phase:
    • Three wire source: Must use Open Delta
    • Four-wire source:
      • Use Open Delta if only need three wires for load
      • Use Wye configuration for all four-wire applications.
        Note: Wye configurations offer expanded kVA Capacity - so try if Open Delta does not meet your requirment.
  • Step Two: Input Source Voltage
  • Step Three: Start changing the voltage change percentage until desired voltage appears in either the buck or boost windows (Exact voltage might not appear, please pick closes voltage: 240 required from 208, 236 is closest voltage)
  • Step Four: Choose the voltage that will be used. (Buck or Boost)
  • Step Five: Input Load Amps
       Calculate Load Amps by inputting Load kVA
  • Step Six: If source is 50HZ click yes for required

Calculator will then calculate Proper Square D Buck Boost Transformer and wiring diagram.

OUTPUT from Tool:
  • Part number
  • Units required
  • kVA capacity using the diagram
  • Wiring Diagram
  • Options for printing and e-mailing


Phase: Single Phase
Three Phase Open Delta
Three Phase WYE
Available Voltage:
Voltage Change: %
Boost Voltage:
Buck Voltage:
Load Current:
Calculate from KVA:
50Hz Required? Yes No


Square D Buck/Boost Site

Buck Boost Catalog

Instruction Bulletin:
   Voltage Code 43
   Voltage Code 46
   Voltage Code 82