100Base-Fx - Siemens SCALANCE X-400 Operating Instructions Manual

3.3.2.3

100Base-FX

Transmission rate
The transmission rate of the optical Fast Ethernet ports is 100 Mbps.
Transmission mode
Transmission with 100Base-FX is defined in the IEEE 802.3u standard and is specified as
100 Mbps transmission rate and full duplex.
Transmission medium
Data transmission is over multimode or single mode fiber-optic cable (FOC).
Two FOC types can be used:
● Multimode FOC
T he core diameter is 50 µm; the light source is an LED. Many modes are used for signal
transmission. The propagation times of the light pulses (dispersion) restrict the maximum
range considerably.
● Single mode FOC
T he core diameter is 9 or 10 µm; the light source is a laser diode. To transmit a signal,
only one mode is used greatly reducing dispersion. As a result, the maximum range of
single mode FOC is greater than that of multimode FOC.
Regardless of the type used, the outer diameter of the FOC is 125 µm.
Transmission range
The maximum transmission range (segment length) depends on the module selected and
the FOC. The range is as follows:
● 100Base-FX module and multimode FOC: 3 km
● 100Base-FX-LD module and single mode FOC: 26 km
● 100Base-FX-LH/ LH+ module and single mode FOC: 70 km
Connectors
The connectors used are BFOC sockets or SC duplex sockets with the 100BaseFX LH/ LH+
module.
SCALANCE X-400
Operating Instructions, 06/2015, C79000-G8976-C186-12
3.3 System description of SCALANCE X-400
Description
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