Revision Standard - Active.The guide is intended to assist protection engineers in applying relays and relaying schemes for protection against stator ground faults on various generator grounding schemes. The existing guide is outdated due to rapid technology development. Hence, the revised guide includes new stator ground protection principles that have evolved with the use of new technologies in relay designs. Additional application examples are included, and other issues raised by the users are also addressed. The guide is not intended for the selection of generator or ground connection schemes. IEEE Std C37.101-1993/Incorporates IEEE Std C37.101-2006/Cor1:2007.