This paper presents the design specifications and features of the smart grid software system. This system as a whole (software and hardware) has been designed, implemented, tested and integrated by using the self-developed configurable feeder terminal unit (FTU) product named HN-F650. The most prominent feature of the system is the reconfiguration technology of kinds of protection logic. In the way, users may draw protection logic diagrams using scalable vector graphics (SVG) technology in host machine and download them into remote FTU. Reconfiguration technology, as applied to distribution feeder circuits, makes it possible to consider application of automation to solve tactical problems. The utility planner may use this new technology to not only address such tactical problems but to eliminate or reduce the need for costly system upgrades, thus providing optimal asset management because we may regroup the modules or add new features of the FTU. Companies may make good use of advanced feeder automation to gain a strategic leverage in serving their customers and meeting increasingly difficult expectations on the part of the users of electric power by using the reconfiguration technology.