*biogas/natural gas generator set *CE/ISO9001 *Four hours test *One year or 1500 ... /Sir, Here some info for your reference. NK series gas generator setGenerator set type20GFT25GFTRated power 20kW25kWRated frequency50/60HZRated voltage400VPower factor0.8Rated ... parallel running system6,Other extend function device 1,NK series generator set is designed, assembled, tested and qualified by Weifang NPT ...