LDS-209 Digital voltage monitoring and automatic paralleling device instruction manual, for the product of the Beijing North China Electric Power University (Beijing) Industry Group Beijing Sifang Lide Protection and Control Equipment Co., Ltd., the device can complete voltage switching function, and increased voltage abnormalities, insulation monitoring, zero sequence voltage, overvoltage, low voltage and other functions, It can realize paralleling, de-paralleling, switching, and bypassing control operations.