Yamasaki Y30 Series User Manual page 21

If the OTDR test mode is set to manual: Click 【Real Time】 in the main menu bar (and 【Real
Time】 is changed to 【Stop】 at this time) to conduct sweep test on the optical fiber link under
test in real time as per the test conditions set at present, and refresh the test curve in the main
operation window continuously. If the OTDR test mode is set to manual: Press the test button or
click 【Avg.】 in the main menu bar (and 【Avg.】 is changed to 【Stop】 at this time) to conduct
average test on the optical fiber link under test as per the test conditions set. The test curve in
the main operation window is subjected to averaging continuously till the average times shown on
the main interface are equal to the set ones, and then the OTDR will stop testing at the same time.
5.3 OTDR test parameters
The OTDR test parameters include the wavelength, range, pulse width, average times, refractive
index, and cable correction coefficient.
Wave length: It is used to set the OTDR test wave length.
 The number of wave lengths allowed by the OTDR depends on the module selected, with
up to 4 wave lengths available for selection.
 Multi wave lengths can be selected in the average test and auto test modes. The
instrument will test all wave lengths in turn till all of them are tested. Up to 4 wave lengths
can be selected for test at the same time.
 If the module selected for the instrument includes both the single-mode and multi-mode
ones, connect the optical fiber under test to corresponding test port, so as to obtain
correct test curves.
Range (km): It is used to set the scanning curve range. The range of the Y3 SERIES70 OTDR
consists of the following levels: 400m, 800m, 1.6km, 3.2km, 8km, 16km, 32km, 64km, 128km,
256km and 512km (which varies with the module selected).
Pulse width (ns): It is used to set the laser pulse width for the test. Large pulses width can be
used to test long optical fibers, with sound test curve SNR, smooth curve, but poor resolution;
small pulses width has high resolution, but can only test short optical fibers, with poor test
curve SNR.
Average times:
It is used set the max. average times of the average test and auto one. The range of such times
is 1-4000 in the average test mode. The range of such times is 5-20 in the auto test mode.
Refractive index:
The refractive index of the optical fiber or cable can be obtained from corresponding
manufacturers. Refractive index can be set to 1.00000～2.00000.
Optical cable correction:
The Optical cable correction factor is provided in view of the difference between the fiber
length and cable one after the fiber changes to the cable. It can be obtained from the cable
manufacturer. The value can be set to 0.80000～1.00000. The default value is 1.00000.
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