CANOGA PERKINS 2345 T3 Fiber Optic Modem - Manual (Page 31)

EdgeAccess Universal Chassis System
Model 2345 User Manual 4-1
Chapter 4
Maintenance and Troubleshooting
Well-maintained modules and cabling can help ensure trouble-free operation.
General Maintenance
Well-maintained components and clearly identified cables help assure optimum system operation.
Damaged fiber cables and dirty connectors are a common source of signal loss or attenuation. Single
mode and multimode fiber optics are especially sensitive to contamination. Inspect, clean, and test all
components to maintain optimum performance.
Note: To avoid damage and signal loss, do not over-tighten or force-fit optical connectors.
• To clean the ferrules and end-face surfaces of male fiber couplings, use a lint-free pad saturated
with isopropyl alcohol.
• To clean the female fiber connectors, use canned air.
• To prevent damage and contamination, place protective dust caps on all unused optical
connectors.
Manage Cable Links
Manage the cables to ensure trouble-free operation and maintenance tasks.
• Position and secure the fiber optic cables to prevent excessive bends and damage. Follow the
guidelines for the bend radius for specific fiber cables.
Note: If no minimum bend radius is specified, the typical long-term, low-stress radius is not less
than 15 times the cable diameter (based on Federal Standard FS-1037C).
• Always connect the fiber optic cables in the standard Tx to Rx and Rx to Tx scheme; reversing
this can cause transmission conflicts.
• Label each fiber cable near each end with the signal direction, source, and destination to
minimize connection errors.
Check Optical Power Levels
To ensure the proper performance levels, measure the fiber link loss, or link attenuation, for all fiber
links. Each 2345 is shipped with a document that lists the output power for each laser transmitter. To
determine link attenuation, use either the 2345 Tx source or a hand-held 1310/1550 nm laser source, a
fiber optic test jumper cable (with known loss), and an optical power meter.
Measure optical fiber links at the shortest wavelength of operation to determine the limiting factor in
the loss budget. Each device that transmits to a 2345 has a loss budget that is specified by the
manufacturer and recorded on a data sheet provided with the equipment. That loss budget must be
greater than the total of the measured loss of the fiber link and the attenuation of the 2345.