... Protective Device 3,Customer first,sincere cooperation power surge protector BX,voltage surge protection device,SPD Surge Protective Device:Application: ... over voltage.As per the conditions of IEC61643-1:1998-02 stand,Class I surge protectuve device,it is category ... B surge protective device. Specifications: TSPD-BX/4P Nominal operating voltage (Ux) 380νMaximum continuous operating ...