OTDR Details Screens - DTX Compact OTDR Module

On the Event Table, you can highlight an event, and then press F3 View Details to see more information about the event.

Use the softkeys to move among the details screens. Listed below are details that may appear on these screens.


OTDR Measurement Details

Length

• Shown on the Overall Results screen.
• Status: PASS means the length is within the limit. FAIL means the length exceeds the limit.
• Value: The length measurement in meters or feet.

Loss

• The optical power lost over the event.
• Status: PASS means the loss is within the limit. FAIL means the loss exceeds the limit.
• Value: The loss measurement in dB.
• Limit: The maximum loss allowed by the selected test limit.
• Margin: The difference between the limit and the measured loss. Margin is negative if the loss exceeded the limit.

Attenuation Coefficient

• Shown on the Overall Results screen. The attenuation per kilometer for the entire length of the cabling. This value may not be shown if it could not be measured accurately.

Segment Attenuation Coefficient

• The attenuation per kilometer for the fiber segment before the event. This value may not be shown if it could not be measured accurately. This can occur on short segments or if the connector before the segment has a large deadzone.

Reflectance

• The power of the light reflected back to the OTDR from an event. A smaller (more negative) reflectance value means less light is reflected back. For example, a good connection may have a reflectance of -45 dB.
• A dirty connection that reflects more light back to the OTDR may have a reflectance of -20 dB.
• Reflectances that exceed the tester's measurement range are shown as the largest measurable value.
• Reflectance measurements are affected by the backscatter value entered in Setup.

Warnings

• No fiber attached or fiber too short:
• No fiber is connected to the tester's OTDR port or launch fiber.
• The fiber is too short for the tester to detect events after the first deadzone.
• There is a bad connector or broken fiber within a few meters of the tester or launch fiber.
• There is a problem with the launch fiber or patch cord.
• The Pulse Width is too long.
• The launch fiber is too short.

• No signal detected:
• There may be a problem with the module. If the error persists, contact Fluke Networks for assistance.

• Unable to find end of fiber due to weak signal:
• The fiber or connections have too much loss.
• For 850 nm, the fiber length exceeds the tester's measurement range.

• End of fiber is beyond range:
• The fiber length exceeds the tester's measurement range.
• If the tester is in Manual OTDR mode, the selected range is shorter than the fiber under test.