Hold the result when
The system is unbalanced, distorted, PWM-fed or rapidly changing; phase and line quantities are mixed; or true power factor and displacement power factor are not distinguished.
GLOBAL-TOOL-14 · TOOL-001 v0.2.0 · AVAILABLE
Single-phase and balanced three-phase power relationship calculator
Calculate active power P, voltage V, current I or power factor PF. The result keeps the original formula, rearranged formula, substituted base-unit values and field assumptions visible.
What this tool does not decide
It does not select or approve conductors, breakers, fuses, protection, contactors, transformers, generators, UPS/BESS, short-circuit duty, arc-flash risk or thermal capability.
Calculation inputs
Calculation result
Calculated value—not acceptanceApplied mode
Original relationship
Rearranged formula
Substitution in base SI units
Unrounded displayed-unit result
Input summary
Assumptions
- Single-phase AC or balanced three-phase AC represented by the entered values
- Three-phase voltage is V_LL and current is I_L
- P is active electrical power, not mechanical motor output
Hold or use another method
- Unbalance, harmonics, distorted waveforms, PWM or changing load
- Meter RMS performance, location, time or PF definition is unclear
- Protection, conductor, short-circuit, arc-flash or thermal study
Field context for the print record
These fields are not saved or transmitted. Enter only what is appropriate for the document you intend to print.
Primary sources and application boundary
- Schneider Electric — TeSys T metering and monitoring functions: single-phase and balanced three-phase active-power relationships using RMS voltage, RMS current and power factor.
- IEC 80000-6:2022: quantities and units for electromagnetism.
- NIST SP 330 (2019): SI unit names and symbols.
Sources reviewed 23 July 2026. They support the relationship, terminology and units only. Confirm jurisdiction, site procedures, measurement method, system topology, OEM documentation and responsible technical review before field use.