Established methods for the resolution of an unbalanced system into positive-and negative-sequence components are extended to give information about their relative phase-displacement. The method developed depends on the inherent property of dynamometer instruments that, for given currents in the coils, the deflection is proportional to the cosine of their phase difference.A dynamometer instrument of ordinary design was modified simply for the purpose by separating the coils and connecting the ends to external terminals, two similar resistance-capacitance networks being added.If it is assumed that the zero-sequence component is absent, or has been eliminated, three readingsr1,r2andr12and one unrecorded test of a qualitative nature are sufficient for a complete analysis. The test serves to determine the sign of the phase angle, the sequence componentsr1andr2are given directly, and the expression cos π=r122/(r1r2) enables the phase angle to be found. The only calculation is very simple, and the solution can be obtained quickly from nomogram.