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ConcentratorBaseRealTime Property
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Gets the most accurate time value that is available. If
UseLocalClockAsRealTime =
true, then
this function will return
UtcNow. Otherwise, this function will return the timestamp of the
most recent measurement, or
UtcNow if no measurement timestamps are within time deviation
tolerances as specified by the
LeadTime value.
Namespace: GSF.TimeSeriesAssembly: GSF.TimeSeries (in GSF.TimeSeries.dll) Version: 2.4.194-beta
Syntax
Remarks
Because the measurements being received by remote devices are often measured relative to GPS time, these timestamps
are typically more accurate than the local clock. As a result, we can use the latest received timestamp as the best
local time measurement we have (ignoring transmission delays); but, even these times can be incorrect so we still have
to apply reasonability checks to these times. To do this, we use the local system time and the
LeadTime
value to validate the latest measured timestamp. If the newest received measurement timestamp gets too old or creeps
too far into the future (both validated + and - against defined lead time property value), we will fall back on local
system time. Note that this creates a dependency on a fairly accurate local clock - the smaller the lead time deviation
tolerance, the better the needed local clock accuracy. For example, a lead time deviation tolerance of a few seconds
might only require keeping the local clock synchronized to an NTP time source; but, a sub-second tolerance would
require that the local clock be very close to GPS time.
See Also