EXFO FTB-7000 OTDR for FTB-200 v2 - Manual (Page 43)

Preparing Your OTDR for a Test
OTDR 29
Setting Macrobend Parameters
Setting Macrobend Parameters
Note: This function is available both in Advanced and Auto modes.
Your unit can locate macrobends by comparing the loss values measured
at a certain location, for a certain wavelength (for example, 1310 nm) with
the loss values measured at the corresponding location, but for a greater
wavelength (for example, 1550 nm).
The unit will identify a macrobend when comparing two loss values if:
³
Of the two loss values, the greater loss occurred at the greater
wavelength.
AND
³
The difference between the two loss values exceeds the defined delta
loss value. The default delta loss value is 0.5 dB (which is suitable for
most fibers), but you can modify it.
You can also disable macrobend detection.
Note: Macrobend detection is only possible with singlemode wavelengths.
Filtered wavelengths or wavelengths of dedicated OTDR ports are not
available for macrobend detection.
For information on how the information about macrobends is available
after an acquisition, see Linear View on page 108 and Summary Table on
page 110.