Phasor diagrams, complex power S = P + jQ, real/reactive/apparent power, and the power triangle. Pick a load (R, L, C, RL series, RC series, RLC series) or type in your own impedance. Edit Vrms, current, phase, or frequency; the waveforms, phasors, and triangle redraw instantly.
S = Vrms · Irms* = P + jQ (VA)
P = Vrms · Irms · cos φ = |S| · pf (W)
Q = Vrms · Irms · sin φ (VAR)
|S| = Vrms · Irms = √(P² + Q²) (VA)
pf = cos φ = P / |S|
P is the horizontal leg, Q is the vertical (Q > 0 inductive, < 0 capacitive), |S| is the hypotenuse, φ is the angle from P to |S|.
p(t) = v(t)·i(t) = Vm·Im·[cos φ + cos(2ωt + θv + θi)]/2
R: P = V²/R, Q = 0, pf = 1
L: P = 0, Q = V²·BL = V²/(ωL)
C: P = 0, Q = −V²·BC = −V²·ωC