The real-time systems are defined as those systems in which the correctness of the system depends not only on the logical result of computation but also on the time at which the results are produced. The system must not only produce logically correct results, but it must also produce them with certain timing constraints. Such systems are gaining importance in a number of applications: automated factories, telecommunication systems, defense systems, and space systems, for example. An expert system (ES), which is been developed as an open system, solves fault diagnosis and restoration problems in low voltage distribution automation. It can be executed successfully whenever there is necessary input data available. The integration of this ES to a real time application has added some features to it. The real time application acquires input data from the distribution system network and delivers it to the ES. And it also accepts output data from the ES and delivers it to the distribution system network. Here, the distribution system network is automated by a Supervisory Control and Data Acquisition (SCADA) system, which is a repository of low voltage distribution network related data.