FIELD: electrical engineering; surge voltage protective gear. SUBSTANCE: device has first protective stage built around gas-filled arresters connected to input leads and second stage built around double-ended semiconductor voltage limiters connected into multiple-wire (N + 1) star (bidirectional diode thyristors, varistors, or double-ended voltage regulator diodes). N circuits of star of semiconductor voltage limiters have similar parameters and are connected to output leads to ensure equal operating voltages of differential-surge protective gear. Finishing lead of (N + 1) star circuit is connected to ground lead and forms, together with respective circuits out of remaining N circuits, cophasal surge protective gear. Semiconductor voltage limiters are first to respond to surge voltages, then respective arresters operate. In case of cophasal surges between ground and any of line conductors (N + 1) semiconductor voltage limiter connected to ground lead and respective semiconductor voltage limiters of N remaining circuits operate. In the event of differential surges between line conductors only associated N-circuit semiconductor voltage limiters operate without (N + 1) limiters. In this way optimal protection is ensured between any conductors of N-wire lines due to separate setting of threshold operating voltages for cophasal and differential surges. EFFECT: optimized protection for all line conductors. 5 cl, 6 dwg
