PRELIMINARY ENGINEERING TOOL
Three-phase neutral current calculator
Estimate the fundamental neutral current from three phase-current magnitudes separated by 120°.
Inputs
Calculation steps
I_N = √(100² + 80² + 60² − 100×80 − 80×60 − 60×100)
Radicand: 1200.0000
Formula ID: NEUTRAL_CURRENT_120_DEG_V1
Assumptions and references
Sinusoidal fundamental phase currents are separated by 120°. Zero-sequence harmonics and waveform distortion are outside this calculation.
UNDERSTAND THE TOOL
What this calculator does
Vectorially add three fundamental phase-current magnitudes. Equal phase currents cancel; unequal currents leave a residual neutral current.
How to use it
- Enter the RMS fundamental current for L1, L2 and L3.
- Confirm the currents belong to the same operating condition.
- Review the calculated vector residual.
- Use measurement or harmonic analysis for nonlinear loads.
Fields and meanings
- L1 current
- Fundamental RMS current on phase L1.
- L2 current
- Fundamental RMS current on phase L2.
- L3 current
- Fundamental RMS current on phase L3.
- Phase spread
- A descriptive comparison, not a compliance limit.
Review required. Triplen harmonics add in the neutral and are not represented by this fundamental-only calculation.
Read the full explanation →