The participation of a large number of distributed loads in frequency control can improve power system security, but the conventional centralized control needs costly high -speed communication channels and the distributed methods lack sufficient global accuracy. To address the above problem, the cyber-physical design of an IoT-enabled system,“Grid Sense”is presented, and it features a local power loss estimation approach for frequency emergency control based on coordinated edge intelligence. Based on the design, smart outlets of Grid Sense detect the frequency disturbance event locally using the parameters sent from the control center to estimate active power loss in the system, and to make rapid and accurate switching decisions soon after a severe contingency.Numerical simulations and hardware experiments are conducted,and it is shown that Grid Sense can accurately and rapidly prevent the drop of frequency after a major power loss with great speed, accuracy and robustness.