The problem is that OpenPDC (historian) changes the data format of the timestamp, to a format different from those output by PMUs. We get the proper time frame when we check it using both pmu tester and OpenPDC graph visualizer, but when we get the values from the historian (MySQL database) the timestamp value does not relate to any time format.
To clarify the problem:
Our data samples (Ado output adapter-Mysql database) looks like below.
PMU ID TIMESTAMP Value (angle)
6dbfb2e6-4f1d-4e5e-ae60-eefd5fe81c15 636268434320000000 -91.08