Why can I operate my Type S or SS capacitor at 100 kV in air, if it is rated at 100 kV?
Type S and SS capacitors were originally developed for Marx generators where low inductance was critical to performance. In such applications, it is common to immerse the entire Marx circuit in transformer oil or a pressurized dielectric gas such as SF6 (sulfur hexafluoride), so that spacing between conductors at different polarities can be minimized. The external strike and creep distances between the electrodes of the Type S and SS capacitors were designed for this environment at up to 100 kV. In ambient air, the design is suitable for operation at up to 75 kV.
