Electrical calculator
Three-Phase Power Calculator
Calculate three-phase power, current, or voltage.
About the three-phase power calculator
The three-phase power calculator calculates power in a three-phase electrical system from voltage, current, and power factor.
How to use this calculator
- 1
Enter line voltage
Enter the line-to-line voltage.
- 2
Enter line current
Enter the current per phase.
- 3
Enter power factor
Enter the power factor (typically 0.8-0.95).
How the calculation works
P = √3 × V × I × PF for three-phase systems. √3 ≈ 1.732.
Example: 480V, 50A, 0.8 PF = 33.3 kW.
Safety first
These calculators provide estimates based on standard formulas and NEC guidelines. Always verify results with a licensed electrician before making installations. Electrical work can be dangerous — never work on live circuits, and always follow local building codes and regulations.
Understanding electrical units
Voltage (V) is electrical pressure, current (A) is flow rate, resistance (Ω) opposes flow, and power (W) is the rate of energy use. Ohm's law (V = I × R) relates the first three, while power formulas (P = VI, P = I²R) connect all four. Understanding these relationships is key to safe electrical design.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about three-phase power calculator
How accurate is the three-phase power calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.