Three-phase

Three-phase meaning for Australian 400 V a.c. notes, board records and calculator inputs.

  • Supply and switchboards
  • Last checked 2026-07-13

Three-phase in Australian records

Three-phase describes an a.c. arrangement using three phase or line conductors. AUWiring commonly uses it beside Australian 400 V line-to-line context, especially for load-current conversion, switchboard notes, phase balancing and cable calculations.

The term should stay attached to the voltage basis and the value being reviewed. A three-phase kW-to-current calculation, a phase-balancing worksheet and a voltage-drop note all use the phrase differently, even though they share the same supply arrangement label.

Where 400 V context appears

Three-phase wording appears in load-current calculators, phase-balancing tools, supply-voltage tables, switchboard load schedules and motor or generator notes. It confirms that the note is not using a single-phase relationship.

Three-phase context
Record contextKeep visibleWhy it matters
Load-current conversion400 V basis, power value and phase arrangementShows which current relationship the calculator used
Phase-balancing worksheetper-phase loads or measured currentsKeeps balance review separate from supply type
Switchboard noteboard role and connected load contextPrevents a three-phase label from hiding uneven single-phase loads

Three-phase vs single-phase inputs

Three-phase is not proof that a load is balanced. A board can be three-phase while individual phase currents or single-phase loads remain uneven.

It is also not a conductor name. When the record needs conductor roles, active, neutral and protective earth should still be named separately.

Using three-phase values in tools

Use phase balancing for entered phase values. Use load current when converting three-phase kW, VA or kVA records. Use the supply-voltage table for public Australian context, then let the project value control the calculator input where required.

Source and review

Check the terminology source, review timing and Australian application before carrying this term into a project record.

three-phase source basis
ItemValue
SourceAUWiring Australian supply voltage table, terminology registry and released load-current calculator language.
Source typeAustralian terminology
Derivation basisAUWiring Australian glossary term; no controlled AS/NZS text is reproduced.
Last checked2026-07-13
Review intervalAnnual terminology review or sooner if supply-voltage wording changes.
Review triggerUpdate when phase labels, supply table rows or phase-balancing calculator wording changes.
Version usedT09-2026-07-13
Australian applicationAustralia; Australian English low-voltage a.c. terminology.

Term questions

Is three-phase always 400 V?

Use 400 V as the Australian public line-to-line context, but project values still control calculator inputs.

Does three-phase mean the load is balanced?

No. Balance depends on the entered loads or measurements.