| The most important critical task in modern electrical network is the selection of overcurrent protection for circuit and equipment. Certainly, the vital relation between effective overcurrent protection and safety to personnel and property must be fully recognized in this document. Since electrical applications continue to grow at a rapid rate, experience has shown that any carelessness of inadequacies in selecting overcurrent protection can result to shock and fire hazard. Another factor, although less important, is the need for full and throughout overcurrent protection for long reliable life of equipment and systems.; This report explains how to calculate short-circuit current ratings in order to clarify the type of protection required and/or to suit the application. Base on theoretical knowledge apply to real life cases, a simulation of a typical fault applications will be applied in order to verify the validity of the theoretical calculations of the short-circuit currents for the protection and coordination of the circuit versus the results provided by experimental simulation using the software «Blockset».; The electrical systems must be based on overcurrent protection that fully and surely protects against overloads up to the maximum available short-circuit currents. This criteria must be carefully coordinated in order to minimize the extent of electrical outages, and to eliminate nuisance or unwanted circuit openings by operating only when and as required for proper protection of human life and property damages. |
