CABLES
10BASE-T/100BASE-TX Pin Assignments
Use unshielded twisted-pair (UTP) or shielded twisted-pair (STP) cable for RJ-45 connections: 100-ohm Category 3 or better cable for 10 Mbps connections, or 100-ohm Category 5 or better cable for 100 Mbps or
1000 Mbps connections. Also be sure that the length of any twisted-pair connection does not exceed 100 meters (328 feet).
The RJ-45 ports on the switch base unit support automatic MDI/MDI-X operation, so you can use straight-through cables for all network connections to PCs or servers, or to other switches or hubs. In straight-through cable, pins 1, 2, 3, and 6, at one end of the cable, are connected straight through to pins 1, 2, 3, and 6 at the other end of the cable.
Table B-1 10/100BASE-TX MDI and MDI-X Port Pinouts
Pin | MDI Assignment | MDI-X Assignment |
1 | Output Transmit Data + | Input Receive Data + |
2 | Output Transmit Data - | Input Receive Data - |
3 | Input Receive Data + | Output Transmit Data + |
6 | Input Receive Data - | Output Transmit Data - |
4,5,7,8 | Not used | Not used |
Note: The “+” and “-” signs represent the polarity of the wires that make up each wire pair.
Straight-Through Wiring
If the twisted-pair cable is to join two ports and only one of the ports has an internal crossover (MDI-X), the two pairs of wires must be straight-through. (When auto-negotiation is enabled for any RJ-45 port on this switch, you can use either straight-through or crossover cable to connect to any device type.)