Following the bypassing of the defective coils the unit was operated self excited with temporary clamp-on current transformers at the neutral of each stator circuit so as to measure the circulating currents.
Six coils were reconnected from one circuit to another so that no more than one coil would be bypassed in any one circuit.
Following a number of open circuit tests it was found that the lowest circulating current as measured by the split phase CTs occurred when two circuits were interchanged between the two groups of circuits in each of the three phases.
Typical bypassed and reconnected coils are shown in Figure 4.