This paper describes a simple way to detect an grid synchronization failure using an basic the voltage & frequency while it go to abnormal condition or sudden change we must say is landing. In over grid there are an various generating units joint together to power grid ex. Hydro, solar, thermal so on etc say from source to load. As we know frequency or vtg must required for an generating units so, if error will be occurs then grid will automatically disconnected. this will prevent large number of brown out .to solve it their should be system which can warn the grid in advance . these system is based on our microcontroller and various component it also has IC555 for sensing the frequency not voltage .so farther under/over voltage drived from set of the comparator as frequency of the main supply not change so by variable frequency generator an frequency changed. the lamp load glow the system will disconnected.