This tool calculates the apparent power (S) in an electrical circuit based on voltage, current, and power factor. It also supports calculation using resistance, impedance, or reactive power depending on available data.
Apparent power is the vector sum of active and reactive power:
S = √(P² + Q²)
Where:
- S = Apparent power (VA)
- P = Active power (W)
- Q = Reactive power (VAR)
Alternatively:
S = V × I × √3 (for three-phase systems)
S = V × I (for single-phase systems)
Input Parameters:
• Current type – Select the type of electrical current:
- Direct Current (DC): Constant flow from positive to negative pole.
- Alternating Current (AC):
- Single-phase: One phase conductor and one neutral.
- Two-phase: Two phase conductors.
- Three-phase: Three phase conductors (three-wire or four-wire with neutral).
• Voltage – Electric potential difference between two points.
- For single-phase: Enter Phase-Neutral voltage.
- For two-phase or three-phase: Enter Phase-Phase voltage.
• Current – Flow of electric charge through a material (A).
• Active power (P) – Real power consumed by the load (W).
• Reactive power (Q) – Power that oscillates in reactive components (inductors/capacitors) without doing work (VAR).
• Power factor (cos φ) – Ratio of active power to apparent power.
- Value between 0 and 1.
- cos φ = φ = phase angle between voltage and current.
• Resistance (R) – Opposition to DC current flow (Ω).
• Impedance (Z) – Total opposition to AC current flow, including resistance and reactance (Ω).
Note: You only need to enter two known values to calculate the rest. The tool will automatically compute missing parameters.