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Fiberlink® 7820 Series User’s Manual
Fiberlink® 7820 Series
Operating Pointers
Remember to check attenuation of the fiber optic cable. The system will only operate
properly if these specifications fall within the range of the system’s loss budget.
Troubleshooting
Multimode fiber optic cable contains an optical fiber with a light carrying “core” that is
only .0025 inches (62.5 microns) in diameter. Single mode fiber optic cable has an even
smaller “core,” only .00032 to .0004 inches (8-10 microns). This is smaller than a human hair!
Therefore, any minute particles of dirt or dust can easily block the fiber from accepting or
radiating light. To prevent this from happening, always use the provided dust caps when
ever optical connectors are exposed to air. It is also a good idea to gently clean the tip of an
optical connector with a lint-free cloth moistened with alcohol whenever dust is suspected.
The status of the LEDs should provide the first clue as to the origin of any operational
failure. If these are off, it usually means that the fiber is broken or has too much attenuation.
Next, be certain that the input and output signal connections are correct.
An optical power meter, such as the Fiberlink® 6615, a visible light source, such as the
Fiberlink® 6610, and a Three Wavelength Light Source, such as the Fiberlink® 6620, can
greatly assist and expedite troubleshooting of fiber optic transmission systems and are
recommended tools all installers should have available.
Finally, although multimode and single mode devices may look the same, they will not
operate properly together. Using the wrong device or fiber can easily add more attenuation
than specified, resulting in poor overall performance. It should be noted that some of our
fiber optic products support both single mode and multimode fiber in the same unit.
If, after reviewing the above possibilities, the system is still not operating, please contact
the Customer Service Department for further assistance. If you suspect your problem is
caused by the optics or the fiber optic cable, and you have an optical power meter, please
take the appropriate measurements prior to contacting support.
Operating Pointers | Troubleshooting
