EXFO FTB-8510B Guia Del Usuario página 1063

Test Period: Represents the period of time used to calculate the SDT
measurement. Choices are 6 μs to 5 minutes. Unit choices are μs, ms,
s, and min. The default setting is 5 minutes.
On/Off button: Press On/Off to enable/disable the disruption time
measurements. However, the measurement will only start if the test is
already started, or when the test will be started.
Note: Stopping the SDT test will stop the measurement without clearing the
results. The SDT test is automatically stopped without clearing results when
the test is stopped. However, starting the test again while the STD is still On
(enabled) will reset the results before restarting.
Statistics
Total Disruption Count: Indicates the number of disruptions that
happened since the beginning of the SDT test.
Shortest: Indicates the shortest measured disruption time.
Longest: Indicates the longest measured disruption time.
Last: Indicates the length of the last measured disruption time.
Average: Indicates the average length of all measured disruption
times.
Total: Indicates the total length of all measured disruption times.
Unit: Select the unit for the statistics. Choices are μs, ms, s, and min.
The default setting is ms.
Note: When the measured SDT is equal or longer than the Test Period, then the
SDT equals the Test Period time.
SONET/SDH Application
Advanced Tabs
Service Disruption Time (SDT)
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