A medium- or high-voltage switching system for AC current comprising two series-connected switches substantially simultaneously opened by random operated opening means. The first switch is shunted by a series arrangement of rectifiers and of a thyristor having together a reverse voltage rated to withstand the restriking voltage across said first switch. Electronic trigger means feeded by the arcing voltage across the first switch and responsive to the current to be interrupted trigger said thyristor shortly before current zero in the appropriate half-cycle to commutate said current from the switch to the shunt path. The arcing interval of the first switch subsequentially deionizes and the opened second switch prevents application of the recovery voltage to the rectifiers.