Example 7.4 shows that, for a solidly grounded generator, there is enough relay current to operate
the generator differential (32.5 A). As the impedance increases, the differential current falls to just
above relay pickup (0.29 A). Any higher neutral impedance or fault resistance and the relay will
not pick up. On the other hand, since the neutral CT does not have to consider load it can have
any ratio that is determined by the available fault current. In this case, a ratio of 100:5 will result
in a neutral relay current of 14.5 A, enough to operate a relay set at, say, 5.0 A.