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FiberLink 3500 Bi-Directional Series User’s Manual
FiberLink 3500 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 .
Note: If no signal is applied to the 3500 Transmitter, no optical power will be present on the
3500 Transmitter’s output .
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! There-
fore, 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 whenever optical
connectors are exposed to air . It is also a good idea to gently clean the tip of an optical con-
nector 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 6650, a visible light source, such as the Fiber-
Link 6656, and a Dual Wavelength Light Source, such as the FiberLink 6652 for Multimode or
6654 for Single Mode, can greatly assist and expedite troubleshooting of fiber optic transmis-
sion systems and are recommended tools all installers should have available .
Finally, although multimode and single mode devices may look the same, they will not oper-
ate 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 customer service .
Operating Pointers | Troubleshooting
