Nortel Networks 893-862-B User Manual

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893-862-B
 
Fiber Optic Cable Length Limitations
 
The 10BASE-F standard permits you to use fiber optic cables up 
to 2000 meters long. However, the fiber connection must meet:
Optical power budget
Ethernet repeater rules
For more information about simple rules for Ethernet network 
compliance, refer to 
 
Using the BayStack 10BASE-T Hubs
 
.
 
BayStack 10BASE-FL Media Adapter
 
The optical power budget for the 10BASE-FL media adapter is 
shown in 
. Power loss in the link cannot exceed the value 
for the type of fiber optic cable you are using.
Only in-line fiber-to-fiber connections (a connection between 
two fibers terminated with fiber connectors, using a fiber-to-fiber 
connector) count against the optical power budget. The loss in a 
fiber connection at the ends of the link is included in the optical 
power budget and does not count as an in-line connection. 
 
Table 1. 10BASE-FL Optical power budget
Parameter
62.5/125 
 
µ
 
m
50/125 
 
µ
 
m
 
Transmitted power (average)
–20.0 dBm
–25.7 dBm
Receiver sensitivity (average)
–32.5 dBm
–32.5 dBm
Optical power budget
12.5 dB
6.8 dB
 
893-862-B SMF MDA  Page 4  Monday, September 30, 1996  1:32 PM