The transient response of the voltage on the secondary is investigated with following changes in the model. Two instants of switching are considered. Instrument transformers are the integral components of power systems .Capacitive Voltage Transformers (CVTs) are widely used for protection, metering and control applications. The work presents the modeling of CVT by its equivalent circuit. A 420kV CVT is considered with a line to ground fault on the primary side. Another kind of transient response called ferro resonance is also studied. Three types of ferro resonance suppression circuits (FSCs)...