The AC electronic voltage transformers are applied to gas- insulated box-type switches with rated frequency of 50Hz and rated voltage of 10kV. It can output high-precision zero sequence voltage signals used by measurement and control devices. This product realizes primary and secondary integration with switch bodies including ZW20/ZW28, FTU as well as other equipment, and with features of small size, light weight, excellent performance, reliable operation, easy installation and so on