A capacitor provides a plurality of selectable capacitance values, by selective connection of six concentrically wound capacitor sections of a capacitive element each having a capacitance value. The capacitor sections each have a respective section element terminal at a first end of the capacitive element and the capacitor sections have a common element terminal at a second end of the capacitive element. A pressure interrupter cover assembly is sealingly secured to the open end a case for the element and has a deformable cover with a centrally mounted common cover terminal and a plurality of section cover terminals mounted at spaced apart locations. A conductor frangibly connects the common element terminal of the capacitive element to the common cover terminal and conductors respectively frangibly connect the capacitor section terminals to the section cover terminals. Deformation of the cover caused by failure of the capacitor element breaks at least some of the frangible connections sufficient to disconnect the capacitive element from an electric circuit in which it is connected. A cover insulation barrier mounted on the deformable cover, has a barrier cup substantially surrounding the common cover terminal and a plurality of barrier fins each extending radially outwardly from the barrier cup, and deployed between adjacent section cover.