Power Budget Calculations For P62-Series Fiber Media - GarrettCom Hardened Ethernet Switches P62F Installation And User Manual

Magnum P62-Series Hardened Switches
longer distances, about 20Km with the single-mode SC.
The same procedures as for multi-mode fiber apply to single-mode fiber connectors.
Follow the steps listed in Section 3.2.2 above.
3.2.5

Power Budget Calculations for P62-Series 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 using Magnum
products, the following equations should be used:
OPB (Optical Power Budget) = P
where P
T
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
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.
Fiber Speed,
Port
Std.
Module
P62- 100Mb
FX
xMSC
100Mb
P62-
FX
xSSC
100Mb
"Long
FX
Reach"
* Note: The use of either multi-mode or single-mode fiber to operate at 100Mbps speed over
long distances (i.e., over approx. 400 meters) can be achieved
factors are both applied:
The 100Mb fiber segment must operate in full-duplex (FDX) mode, and
The worst-case OPB of the fiber link must be greater than the fiber cable's passive
Attenuation.
(Attenuation = Cable loss + LED aging loss + Insertion loss + safety factor)
www GarrettCom com . .
(min) - P
T
= Transmitter Output Power, and P
Std. km Wave-
fdx length
Mode
(hdx) nm
Multi- 2 1300 62.5/125
mode (0.4)
Single- 20
1300
mode (0.4)
Single-
40
1300
mode
(0.4)
Installation and User Guide (12/02)
(min)
R
= Receiver Sensitivity
R
(m.m.) is 2.8 dB/km,
m
Cable X'mitr R'cvr
Size Output Sens.
P dB P dB
m
T , R ,
-20 -31
50/125 -23.5 -31
9/125 -15 -31
9/125 -5 -34
23
Worst Worst* typical
OPB, distance OPB,
dB Km, fdx dB
9.0 2.5
5.5 2.0
14 28 17.5
27 54 32.5
only
if the following
typical*
distance
Km, fdx
14 5
12 4
35
65