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3.4 100BASE-FX Module
The 100BASE-FX port module supports a connection to a Fast Ethernet network segment through a fiber optic connection. The module comes with two ST connectors. One labeled Tx is used for transmission. The other one labeled Rx is used for reception.
Figure 3-3 100BASE-FX Port Module
When connecting to a 100BASE-FX device using fiber cable, make sure the Tx connector of the module is connected to the Rx connector of the device and Rx connector is connected to the Tx connector of the device.
The required fiber optic cable for the connection is 1300nm 62.5/125 mm fiber cable. The maximum distance between the module and the connected device depends on the device connected and the duplex mode used for the connection as follows:
Device connected | | Duplex mode | Maximum length |
Computer 100BASE-FX port | Half-duplex | 400 meters |
Computer 100BASE-FX port | Full-duplex | 2K meters |
100BASE-FX hub port | | Half-duplex | 185 meters |
100BASE-FX switched | port | Half-duplex | 400 meters |
100BASE-FX switched | port | Full-duplex | 2K meters |
Note:
The 100BASE-FX module does not support auto-negotiation function. When the port is set at auto-negotiation mode, it will operate in half- duplex mode automatically.