Nortel Networks BayStack 893-862-B - Manual (Page 6)

4 893-862-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
Table 1 . 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