Fluke OF-500-10 Technical Reference Handbook page 186

OF-500 OptiFiber Certifying OTDR
Technical Reference Handbook
Loss is negative.
•
The connections to the tester were disturbed after referencing.
•
The fiber ends were dirty during referencing.
•
There was a kink in a reference reference test cord during referencing.
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The connectors were not properly aligned during referencing.
•
Some other problem caused a bad reference value.
If loss is negative, set the reference again and retest the cabling.
A known length of cable measures too long or too short.
•
The wrong fiber type is selected on the Cable tab in Setup.
•
The index of refraction needs adjustment. Change n on the Cable tab in Setup.
6-42
Table 6-10. Diagnosing Loss/Length Test Failures (cont.)