Arc Suppression Coils The most common type of star point treatment is the high impedance inductive grounding because in case of earth fault wiper or permanent earth fault further operation can be driven without a dark circuit cut-off of the corresponding network district takes place. The arc suppression coil with optimum tuning compensates the capacitive charging current which is flowing through the ground capacitances of cables or overhead lines. The Arc Suppression Coil represents in connection with the ground capacitances a 50 Hz series-resonant circuit. More accurate the tuning of this resonant circuit, the less residual current at the fault location occurs. Through an accurate earth fault compensation or detuning control and a modern Earth Fault Detection System such as phase-earthing equipment a highest level of personal safety and device security is guaranteed. Of course, we also supply neutral earthing- and grounding transformers for coupling the Arc Suppression Coils as well as their combinations to the network. 110kV Arc Suppression Coils are also in our delivery program.