Single or Three-Phase Power?
Answer a few questions about your supply and system size to see whether single or three-phase is the right fit — and why it matters for solar.
- Helps you see whether single or three-phase power is the right fit for your supply and system size.
- Returns a phase recommendation along with the reasoning behind it.
- Points you to what to check, so you understand why phase matters for solar.
Likely supply
—
Select what you can see above to get a result.
You can usually tell your supply type from two visible clues at the switchboard — without touching anything:
- Main switch width. A narrow, single-pole main switch is single-phase; a wide, three-pole (ganged) switch is three-phase.
- Active wires at the meter. One active conductor (plus neutral) is single-phase; three actives is three-phase.
Why it matters for solar: three-phase supply allows larger inverters and more balanced export, while single-phase sites face stricter inverter-size and export limits in many networks. If you can't tell, send your installer a photo — never open the switchboard yourself.
Estimates only — for guidance, not a quote or engineering specification. Nothing you enter is stored or sent anywhere; the maths runs entirely in your browser.
Frequently asked
- Is this tool free to use?
- Yes. The phase checker is free and needs no sign-up. It runs entirely in your browser.
- Is my data stored or sent anywhere?
- No. The tool runs in your browser and stores nothing. Your answers are not saved or sent anywhere.
- Why does single or three-phase matter for solar?
- Your supply type and system size affect which phase suits a solar install. The tool gives a recommendation with reasoning to help you understand the fit, as an estimate rather than a formal assessment.
More tools
Sizing Tool
Solar System Size Calculator
Turn your daily energy use, sun hours and system losses into a recommended array size, panel count and inverter rating.
Financial Tool
Solar Payback Calculator
Estimate annual savings and payback period from system cost, generation, self-consumption, electricity rate and feed-in tariff.
Engineering Tool
Solar Panel Power Density Calculator
From rated power and module dimensions, compute power density in W/m², module efficiency and panels needed per kilowatt.