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IM AQ7280-01EN
Note
Except when the optical fiber cable is short and there are no reflections, we recommend that you measure
with the average method be set to Hi-Reflection.
Average Unit
Duration: Measurements are performed only over the specified duration. If you specify a short
duration, depending on the measurement conditions, measurements may not have
finished when the specified time elapses.
Times: Measurements are performed only the specified number of times.
Average Count and Average Duration
You can select the following values.
Duration: 5 sec, 10 sec, 20 sec, 30 sec, 1 min, 3 min, 5 min, 10 min, 20 min, 30 min
Sec is seconds, and min is minutes.
Times: 2^10 (1024 times), 2^11 (2048 times), 2^12 (4096 times), 2^13 (8192 times), 2^14
(16384 times), 2^15 (32768 times), 2^16 (65536 times), 2^17 (131072 times), 2^18
(262144 times), 2^19 (524288 times), 2^20 (1048576 times)
2^10 is 2 to the power of 10 (1024 times).
• The maximum average count is 2^20. If you specify a duration to average over that causes this
number of times to be exceeded, the measurement will finish before the duration to average over
elapses.
• Due to the influence of other measurement conditions, a measurement may take less time than
the duration you have specified or it may not complete when the specified duration elapses.
• If you specify a large value for the number of times or the duration, you can perform highly
precise measurements, but the measurement time becomes longer. Keep the AQ7280’s dynamic
range and the loss of the optical fiber cable under measurement in mind when you specify these
values.
• The display of the duration or the number of times is determined by the specified average unit.
• If Auto is selected, one of the options above is used.
Fiber-In-Use Alarm
The AQ7280 uses the same wavelength that is used in real communication to measure optical
pulses. If communication light is present in the optical fiber cable that you want to measure, the
communication will be affected. When this communication light is present, we say that the fiber is in
use. The fiber-in-use alarm is a feature that checks if communication light is being transmitted along
the optical fiber cable that you are trying to measure. If the fiber is in use, a warning message is
displayed asking whether you want to continue the measurement.
Connection Check
The connection check is a feature that checks the state of the connection between the AQ7280 and
an optical fiber cable. When this feature is set to on, you can prevent light from being transmitted
from the AQ7280 OTDR port or light source port if an optical fiber cable is not connected to the
AQ7280 or if the cable is not connected correctly.
OFF: Connections are not checked.
ON: Connections are checked.
Event Search
Event search is a feature that automatically searches for losses and reflections in the data that is
acquired during averaged measurements. Losses and reflections detected in waveform data are
known as events. For details on analyzing detected events, see section 4.2.
Auto: After averaged measurements complete, events are automatically searched for and
listed, and the event screen and event analysis menu are displayed.
Manual: After averaged measurements complete, the waveform is displayed, but events are
not searched for.
2.1 Setting the Measurement and Analysis Conditions
