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Investigation of PMU Response to Leap Second: 2015



Allen R. Goldstein, Dhananjay Anand, YaShian Li-Baboud


Between 22:30:00 June 30, 2015, and 00:30:00 July 2, 2015, UTC, the National Institute of Standards and Technology (NIST) tested eight Phasor Measurement Units (PMUs) to investigate their response to the leap second adjustment to UTC which occurred following 23:59:59 UTC on June 30, 2015. At this time, the offset between TAI and UTC time incremented by 1 second from 35 seconds to 36 seconds. None of the PMUs responded to the leap second in accordance with IEEE standard. This NISTIR documents the actual responses of the 8 PMUs investigated.
NIST Interagency/Internal Report (NISTIR) - 8077
Report Number


PMU, Leap Second, Synchrophasor, C37.118, C37.118.1, C37.118.2


Goldstein, A. , Anand, D. and Li-Baboud, Y. (2015), Investigation of PMU Response to Leap Second: 2015, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 24, 2024)


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Created August 24, 2015, Updated November 10, 2018