Fluke OF-500-10 Technical Reference Handbook page 227

Maintenance and Specifications
11
If Something Seems Wrong
Table 11-1. Troubleshooting the Tester (cont.)
Symptom 6: The noise level on the OTDR trace has increased or the OTDR connector reflection has a large deadzone. (See
"OTDR Connection Quality" in Chapter 3.)
The fiber endface in the OTDR connector may be dirty or damaged. Clean the connector and inspect the endface with a
fiber video microscope. If an endface is damaged, contact Fluke Networks for service information.
Symptom 7: The reference test cords and adapters are good, but the reference power level is too low.
Clean the tester's INPUT and OUTPUT connectors and use a fiber microscope to inspect the endfaces. If an endface is
damaged, contact Fluke Networks for service information.
Symptom 8: A loss/length test produces a negative loss reading.
There is a problem with the reference. Set the reference and test the cabling again. See "Diagnosing Loss/Length Test
Failures" in Chapter 6 for details.
Symptom 9: Test results appear to be incorrect.
The tester may not be configured correctly. If you are using Manual OTDR mode, try testing in Auto OTDR mode.
See "Diagnosing OTDR Test Failures" in Chapter 3, "Diagnosing Loss/Length Test Failures" in Chapter 6, and "Power Meter
Results" in Chapter 8 for information on how misconfigurations may affect your test results.
Symptom 10: The message "Selected test limit or fiber type is not valid with this test" appears.
You need to select a different test limit or fiber type. For details see "If the Test Limit or Fiber Type is Not Valid with the
Test" in Chapter 2 or press H when the message appears.
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