EXFO FOT-930 Multifunction Loss Tester - Manual (Page 51)

Measuring Optical Return Loss
Multifunction Loss Tester 43
Performing and Saving ORL Measurements
4. Terminate the fiber as close as possible before the component under
test. Wrap it at least 10 turns around a mandrel or small diameter tool,
adding turns until the reading stabilizes.
5. Press OK to save the ORL zero value, then remove the termination.
To revert to the factory-default ORL zero value:
1. Press Menu, then select ORL Meter.
2. Press Default ORL Zero (F1/F2 key).
Performing and Saving ORL Measurements
You can define ORL thresholds (see Setting Pass/Fail Thresholds on
page 26) before or after measuring ORL. ORL values below thresholds are
displayed in red.
To measure ORL:
1. If necessary, perform an
offset nulling (see Nulling Electrical Offsets on
page 32).
2. Press Menu, then select ORL Meter.
3. Press Wavelength (F1/F2 key) to select a singlemode wavelength.
4. Verify your patchcords and clean them properly (see Cleaning and
Connecting Optical Fibers on page 22).
Note: If the F
AS T ES T SM port of your unit is equipped with an APC connector, use
EXFO’s optional ORL calibrated patchcord.