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Revision of IEEE Std C37.238, Power Profile for IEEE-1588: Why The Big Changes?



Mark Adamiak, Galina Antonova, A. Apostolov, H. Kirrmann, F. Becker, J. Bougie, C. Brunner, W. Dickerson, M. Dood, D. Giarratano, R. Graf, H. Falk, C. Huntley, D. Ingram, Ya-Shian Li-Baboud, K. Martin, R.J. Murphy, B. Muschlitz, M. Renz, G. Rzepka, V. Skendzic, T. Tibbals, B. Vandiver, S. Zimath


Revision and renewal of standards is normally a routine process. This paper describes why revision of the Institute of Electrical and Electronics Engineers (IEEE) C37.238 standard was anything but routine, the reasons why a new approach was needed, and the impacts of the changes on users. By far the most significant change was splitting this standard into two standards: the new joint standard International Electrotechnical Commission (IEC)/IEEE 61850-9-3 and the now revised IEEE C37.238-2017. The reason for the change was that the two main sponsoring organizations IEC Technical Committee (TC) 57 Working Group (WG) 10 and IEEE Power and Energy Society (PES) Power Systems Relay Committee (PSRC) expressed significant differences in their expectations from this work. The result was that IEC/IEEE 61850-9-3 became the technical specification document, providing the baseline performance level required for all applications. Additional requirements supported by the revised IEEE C37.238 include real-time updates of the delivered time's quality (inaccuracy), plus inclusion of the time's data needed to support the migration of substation time-distribution networks from IRIG-B. The paper will describe why re-arranging the standard this way has advantages and disadvantages; discuss the consequences of these changes to the users of the standard(s), and reveal important issues users must keep in mind when migrating to the new version.
Conference Dates
May 2-4, 2018
Conference Location
Atlanta, GA, US
Conference Title
Georgia Tech Protective Relaying Conference 2018


IEEE 1588, PTP, protective relaying, smart grids, time distribution


Adamiak, M. , Antonova, G. , Apostolov, A. , Kirrmann, H. , Becker, F. , Bougie, J. , Brunner, C. , Dickerson, W. , Dood, M. , Giarratano, D. , Graf, R. , Falk, H. , Huntley, C. , Ingram, D. , Li-Baboud, Y. , Martin, K. , Murphy, R. , Muschlitz, B. , Renz, M. , Rzepka, G. , Skendzic, V. , Tibbals, T. , Vandiver, B. and Zimath, S. (2018), Revision of IEEE Std C37.238, Power Profile for IEEE-1588: Why The Big Changes?, Georgia Tech Protective Relaying Conference 2018, Atlanta, GA, US, [online], (Accessed July 19, 2024)


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Created June 14, 2018, Updated October 14, 2021