Operation Manual

Diagnosing Fiber Cabling Faults
Diagnosing Loss/Length Test Failures
10-3
10
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Table 10-2. Diagnosing Fiber Test Failures (cont.)
Loss is negative.
• The fiber ends were dirty during referencing.
• The connections to the tester were disturbed after referencing.
• There was a kink in a test reference cord during referencing.
• The connectors were not properly aligned during referencing.
• The testers were much colder during referencing than during testing.
• Some other problem caused a bad reference value.
• If loss is negative, set the reference again and retest the cabling. See Chapter 8.
A known length of cable measures too long or too short.
• The wrong fiber type is selected on the Fiber Setup menu
• The index of refraction needs adjustment. Change n on the Fiber Setup menu