Vacuum switch assembly

In a direct current shunting switch assembly in which a plurality of vacuum switches are disposed electrically in parallel and adapted to be connected across the electrode terminals of an electrochemical cell, the improvement wherein each vacuum switch is connected independently to separate electrical bus conductors, wherein separate electrical bus conductors extend in electrical parallel bus isolated relationship from each other from the respective vacuum switches to the cell electrode terminal connections, which electrically parallel separate bus conductors extend in closely spaced parallel path relationship to provide minimum self-inductance and mutual inductance effects, so that the energy which is dissipated in the last-to-open vacuum switch during interruption will be minimized, and the resistance value of the separate bus conductors is determined so that the potential across the switch assembly and bus conductors at the electrolytic cell electrode terminals is less than the cell battery potential when the switches are closed to permit shunting of the cell current through the plural parallel paths of the switch assembly, and the resistance value of the separate bus conductors is such that when the switches are opened to divert current back through the electrolytic cell, the current through the last-to-open switch is reduced to a value which can be interrupted without damaging the last-to-open switch.