EXFO FTB-8510B Guia Del Usuario página 1069

No Defect time: Represents the required period of time without defect
that it is needed to collect one disruption time value. Choices are from
10 μs to 2 s in steps of 10 μs. The maximum value is adjusted with
respect to the test period (the max No Defect time is obtained when
the Test Period value is set to its maximum value: 5 min). The default
setting is 300 ms. Unit choices are μs, ms (default), s, and min.
Test Period: Represents the maximum period of time allowed for SDT
measurement. If this time is reached during a defect, the time
measured is logged as an event and a new disruption measurement
event is started. Choices are 20 μs to 5 minutes in steps of 10 μs. Unit
choices are μs, ms, s, and min (default). The default setting is 5 min.
In the case where the duration of a defect is longer than the test period,
more than one disruption event will be reported. Increasing the test
period may ovoid this situation. In the following example, the duration
of the defect is longer than the test period.
SDT Threshold allows to enabled and enter the SDT threshold value
that will be used to declare the pass/fail verdict: 0.001 to 299999.94 ms.
The SDT Threshold check box is cleared by default and set to 50 ms.
Unit choices are μs, ms (default), s, and min.
Note: Stopping the SDT test will stop the measurement process without clearing
the results. However, starting the test again while the STD is still On
(enabled) will reset the results.
SONET/SDH Application
Advanced Tabs
Service Disruption Time (SDT) - Monitor
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