Hello. GPS precision time synchronization is used for power systems where reliability is critical, such as electric utility grid, data centers, hospitals, refineries, etc. For standard applications, power monitoring with 1-second resolution may be enough. But for critical power applications, engineers must distinguish events within 1 ms. Typically, GPS time sync is used in “Sequence of Events Recording” (SER) systems, in which every power system event is recorded within 1 ms. This is necessary for system troubleshooting to know the exact sequence of every action. It can also be useful to record all aspects of a system test to produce a written record of the successful test. Such proof of monthly tests is sometimes required for hospitals and other sites which use stand-by generation.
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