This guide has been prepared to assist the protection engineer in applying relays for the protection of generators from damage caused by internal electrical faults, system faults, or abnormal operating conditions.

This application guide describes the generally accepted forms of protection for synchronous generators and their excitation systems. It summarizes the use and selection of relays and other protective devices that provide generator protection. The guide is primarily concerned with protection against faults and abnormal operating conditions for large hydraulic, steam, and combustion turbine generators (CTGs). The guidance pertains to typical synchronous generator installations. However, sufficient background information relating to protection requirements, applications, and setting philosophy is given to enable the reader to evaluate the need to select and app...

This guide summarizes the use of relays and other protective devices such that the reader may select the necessary equipment to provide adequate protection for ac generators from short circuits and abnormal operating conditions.