| Issue | Cause | Solution |
| The application displays a message indicating that it has found an event of “fiber end unresolved “. | The fiber under test is too long. | Make sure the length of the fiber under test is less than the maximum length the OTDR can measure. |
| A message indicating that there has been a “live fiber error” and that the fiber is not connected to the active SM port appears in the application. | Light has been detected in the OTDR port during acquisition or when a fiber was monitored in real-time mode. | Disconnect the fiber OTDR port. Click OK to close the message. Start another acquisition without any fiber connected to the OTDR. The error message should not appear active fiber and the curve of OTDR should have a “normal” appearance. If you still see the error message fiber active even when no fiber connected to the OTDR, contact EXFO. Never connect an active OTDR port settings without adequate fiber. Any input optical power to be -65 dBm to -40 dBm will affect the OTDR acquisition. The way that the acquisition will be affected depends on the selected pulse width. An incoming signal above -20 dBm could damage your OTDR permanently. For testing of active fiber, check the specifications of the active SM port to see the characteristics of the integrated filter. |
| A message indicating that there has been a “live fiber error” and that the fiber is connected to active SM port appears in the application. | The power level in the integrated filter bandwidth SM active port is too high. A wavelength of the transmission network may be too close to the active SM wavelength. | Disconnect the fiber OTDR port. PulseAceptar to close the message. Start another acquisition without any fiber connected to the OTDR. The error message should not appear active fiber and OTDR curve should have a “normal” appearance. If you still see the error message active fiber even when no fiber connected to the OTDR, contact EXFO. The proof of active fiber single mode requires that the integrated test channel power (corresponding to the bandwidth of the filter SM active) port is as low as possible. An incoming optical power of -65 dBm and -40 dBm will affect the OTDR acquisition capability. The way in which the acquisition is affected depends on the selected pulse width. A higher power levels preclude the acquisition is made. Check the compatibility of the network with wavelength SM active. Ensure that the network does not transmit wavelengths above 1600 nm. |
Source from EXFO OTDR Users Manual
