Cabletron Systems 2208 manual Connecting a Twisted Pair Segment to the FE-100TX

Chapter 3: Installation

3.6.1Connecting a Twisted Pair Segment to the FE-100TX

NOTE

To ensure proper operation, use only Category 5 Unshielded Twisted Pair (UTP) cabling that has an impedance of 85 to 111 ohms.

An FE-100TX installed in port slot 7 and/or 8 has an internal crossover switch. When connecting a workstation, use a straight-through cable and set the Fast Ethernet Interface Module crossover switch shown in Figure 3-6to the straight-through position marked with =. To connect networking devices, such as another switch, repeater, or router, use a crossover cable or flip the crossover switch to the crossed over position marked with an X as shown in Figure 3-6.

Position X (crossed over)

1.RX+ 5. NC

2.RX- 6. TX-

3.TX+ 7. NC

4.NC 8. NC

x =

10

100

FE-100TX

Position =

(not crossed over)

1.TX+ 5. NC

2.TX- 6. RX-

3.RX+ 7. NC

4.NC 8. NC

16651_05

Figure 3-6 FE-100TX Crossover Switch

A schematic of a crossover cable is shown in Figure 3-7. If the wires do not cross over, use the switch on the FE-100TX to internally cross over the RJ45 port.

RJ45 Port			10BASE-T Device Port
RX+	1			1	RX+
RX–	2			2	RX–
TX+	3			3	TX+
TX–	6			6	TX–
		RJ45 to RJ45			2251-31

Figure 3-7 Cable Pinouts - RJ45 Crossover Cable

Page 3-8 2H22-08R SmartSwitch 2208 User’s Guide