Revision Standard - Inactive-Withdrawn. Withdrawn Standard. Withdrawn Date: Jan 17, 1997. No longer endorsed by the IEEE. The need for standard terminology in the field of automatic generation control (AGC) became apparent when it was noted that authors of technical papers covering this technology frequently used different terms to convey identical meanings. This inconsistency of terms and requests for standardization from operating organizations of interconnected power systems in both the United States and Canada led to the original development of these definitions. This publication is the second revision of these terms. It illustrates the continuing need to standardize commonly used terminology unique to AGC. In addition, term definitions are intended principally as references, not as tutorial substitutes for training in this control field. The definitions provide simplified, unambiguous meanings for individuals having a basic understanding of AGC technology.