Explain the difference between transient and residual current
Residual current is mainly caused by inductive reactance in coils, charged capacitors, magnetic field cutting conductors. Residual circulating currents could also be generated in switched off overhead line due to capacitance. Transient currents are mainly caused by faulty conditions eg, when you lose one phase in a 3 phase system, the neutral and earth will no longer be at zero potential, when lighting strike you expect some faulty currents passing through circuit and conductors damaging electrical appliances and other things any fault currents passing earth and going to Substation earthing or earth pit are transient currents