- The matrix on the previous slide says any three phasors are three balanced sets added together. This is that sentence, drawn.
- Positive spins a–b–c, negative spins a–c–b, and zero has all three on top of each other.
- Change what the fault leaves on the phases and watch which sets survive — that pattern is the whole diagnostic.
One phasor on phase a alone gives I₀ = I₁ = I₂ = Ia/3: three equal sets, in line with each other.
Left: what the disturbance leaves on the phases. Right: the same currents as three balanced sets.