FZN21-12 Series Indoor High Volgate Break Switch 1 ISO9001:2000 2 12KV 3 Safty,Perfect,Loss ... composition of high-voltage vacuum load switch for three-phase AC electrical 12kV, 50Hz power distribution system, with a compact, small size, ... appliances), to replace fuses with higher cost, its operating and maintenance easy and convenient.maintenance. FZN21-12-Model load switch and the combination of ...