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FT14 and FT14H 10Mb Media Converters Installation and User Guide (09/09)
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6.
For the Link Pass-through model, connection is the same except that the LINK indication
will not be present unless LINK is made for the cables on both sides.
3.6.3
Power Budget Calculations for Fiber Media
Receiver Sensitivity and Transmitter Power are the parameters necessary to
compute the power budget. To calculate the power budget of different fiber media
installations, the following equations should be used:
OPB (Optical Power Budget) = P
T
(min) - P
R
(min)
where P
T
= Transmitter Output Power, and P
R
= Receiver Sensitivity
Worst case OPB = OPB - 1dB(for LED aging) - 1dB(for insertion loss)
Worst case distance = {Worst case OPB, in dB} / [Cable Loss, in dB/Km]
where the “Cable Loss” for 62.5/125 and 50/125
μ
m
(M.m) is 2.8 dB/km,
and the “Cable Loss” for 100/140 (Multi-mode) is 3.3 dB/km,
and the “Cable Loss” for 9/125 (Single-mode) is 0.5 dB/km
The following data has been collected from component manufacturer’s (HP’s and
Siemens’) web sites and catalogs to provide guidance to network designers and installers.