When the snubber capacitor is used as part of a network, it is not always possible to mount the capacitor directly to the IGBT. The same is true when the IGBT is PC board mounted. For those cases, use the KEMET radial box series C4A. The same selection guidelines apply except that if the capacitor is part of a network, the initial capacitance of 0.25µF per 100A of IGBT current can be tried.