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Switch Ventilation Fan

The PowerConnect 2748 switch has three fans and
the PowerConnect 2724 switch has one fan for
system ventilation. The PowerConnect 2708 and PowerConnect 2716 devices have no internal fans.
Cables, Port Connections, and Pinout Information
This section explains the switch physical interfaces, and provides information about cables and
port connections. Copper cable diagnostics are supported. High-speed workstations, hubs, routers,
or other switches are connected through standard RJ-45 connectors to the switch physical interface
ports, located on the front panel. For each device, the supported mode is set to Half Duplex, Full
Duplex, and Auto.

1000BASE-T Cable Requirements

All Category 5 UTP cables that are used for 100BASE-TX connections also operate with 1000BASE-
T, provided if all four wire pairs are connected. However, it is recommended that enhanced
Category 5 (Category 5e)cable is used for all critical connections or any new cable installations.
The Category 5e specification includes test parameters that are only recommendations for
Category 5, and comply with the IEEE 802.3ab standards.

RJ-45 Connections for 10/100/1000BASE-T Ports

The 10/100/1000BASE-T ports are copper Twisted-Pair ports.
Table 2-6. Ports, Connectors and Cables
The following figure illustrates the RJ-45 pin connector pin numbers.
Figure 2-10. RJ-45 Pin Numbers
The RJ-45 pin number allocation for the 10/100/1000BASE-T ports is listed in the following table.
Connector Port/Interface Cable
RJ-45 10/100/1000BASE-T Port Cat.5