Chart

Common voltage systems chart

Reference common nominal voltage systems used in Canadian residential, commercial, and industrial work.

Chart boundary

Not a utility service approval, design instruction, or product rating.

one line

Voltage system context

Use the system label to choose the right calculator preset before doing project-specific arithmetic.

Scopevoltage systemsX-axisnominal utilization voltageY-axiscommon system contextReviewAnnualNextVoltage drop calculator
Voltage system context120 V / 240 VSingle-phase branchUse for many reside...120/208 VCommercial wyeSeparate line-neutr...347/600 VCanadian industrialCommon for larger c...Measured or spe...Project checkThe nominal label i...
Use the system label to choose the right calculator preset before doing project-specific arithmetic.
120 V / 240 VSingle-phase branch
  • Use for many residential and small-load presets.
120/208 VCommercial wye
  • Separate line-neutral and line-line loads before calculating.
347/600 VCanadian industrial
  • Common for larger commercial and industrial distribution.
Measured or specified voltageProject check
  • The nominal label is not a service approval.
Single-phase branch120 V / 240 V
Commercial wye120/208 V
Canadian industrial347/600 V
Project checkMeasured or specified voltage

Decision reference

Show common nominal voltage systems and calculator preset context.

Common Canadian nominal system categories prepared for calculator presets; utility-specific service requirements are outside this page.
Nominal systemPhaseCommon contextCalculator presetField note
120 VSingle-phase loadLighting, receptacles, controls, and small equipment120 V single-phase loadOften derived from a 120/240 V or 120/208 V system.
120/240 VSingle-phase, 3-wireDetached houses and many small services240 V single-phase line-to-lineUse the actual load voltage in a calculation.
120/208 VThree-phase, 4-wire wyeCommercial buildings and multi-unit residential distribution208 V three-phase or 120 V line-to-neutralLine-to-line and line-to-neutral loads need different voltage inputs.
347/600 VThree-phase, 4-wire wyeCanadian commercial and industrial distribution, including some lighting and mechanical loads600 V three-phase or 347 V line-to-neutralConfirm equipment ratings and local rules before applying.
600 VThree-phase loadIndustrial motors, distribution, and larger equipment600 V three-phaseDo not infer fault current, protection, or conductor ampacity from voltage alone.

Use notes

  • The chart is a routing and reference aid, not a utility service standard.
  • Always confirm the actual service and utilization voltage for the project.
  • Some installations use other systems or utility-specific service arrangements.

Reference sources

Open the underlying public references before treating the chart as project guidance.