What your readers can do with it
Most three-phase mistakes come from mixing line and phase values or forgetting the √3. The three-phase power calculator shows both sets of values side by side and draws the power triangle, so readers see where each number comes from. It has three tabs, and the 50 or 60 Hz and kW or hp settings apply to all of them:
- Power: star or delta, three-phase or single-phase, starting from the current or from the power. Out come P, Q, S, line and phase voltages and currents, and the impedance per phase.
- PF correction: the capacitor bank in kVAR and in µF per phase for delta or star, the current before and after, and a resonance check against the supply transformer.
- Motor current: full-load current from the nameplate output, voltage, efficiency and power factor.
Where it fits
An electrical machines or power systems course can embed it under a worked star and delta example. A maintenance blog can open it on the PF correction tab in a post about utility power factor charges, so plant engineers try their own kW and target. Panel builders can put the motor current tab on a page about sizing feeders and starters.
Suggested size
The default frame is 1,200 px high and up to 960 px wide: the inputs on the left and the results on the right, with the power triangle and working lower down. The full tool is about 1,510 px tall at that width, so 1,550 px shows everything without scrolling inside the frame. On a phone the two columns stack to about 2,120 px.
Open it on a power factor correction problem
This link sizes a capacitor bank to raise a 100 kW load from a power factor of 0.75 to 0.95, on a 1,000 kVA transformer with 6% impedance:
https://widemath.com/embed/three-phase-power-calculator/?tab=pfc&p=100&pf1=0.75&pf2=0.95&tr=1000&z=6
At 400 V and 50 Hz the widget asks for 55.32 kVAR, which is 366.9 µF per phase in delta, and the line current drops from 192.5 A to 151.9 A. The resonance check puts the bank's resonance at the 17.4th harmonic, clear of the 5th, 7th, 11th and 13th. Add &hz=60&vl=480 for a North American supply.
Add it in three steps
- Load the problem or keep the default star load, set the height, and press Copy embed code.
- Paste it into the HTML of your post or course page.
- State the supply your example assumes (400 V 50 Hz or 480 V 60 Hz), so readers outside your country change the right setting.
Frequently asked questions
Does it handle both star and delta?
Yes. Readers pick star (wye) or delta, and the widget shows line and phase values for both voltage and current, with the √3 applied where it belongs.
Why does it ask about the transformer?
A capacitor bank and the supply transformer form a resonant circuit. With the transformer's kVA and %Z, the widget works out the resonant harmonic and warns when it lands near the 5th, 7th, 11th or 13th. Leave those boxes blank to skip the check.
Can it work in horsepower?
Yes. Switch the motor power unit to hp at the top of the tool, or add pu=hp to the link.
More calculator widgets
Want the explanations and worked examples as well? They are on the full Three-Phase Power Calculator page. All 24 widgets, each with a Copy code button, are in the calculator widget gallery.
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