Cabletron Systems SEH-22 User Manual

4-3

Before connecting a segment to the EPIM-T, check each end of the 
segment to determine if the wires are crossed over for the proper 
connection. If the wires do not cross over, use the switch on the EPIM-T 
to internally cross over the RJ45 port. Refer to Figure 4-2 to properly set 
the EPIM-T crossover switch.

Figure 4-2. EPIM-T Crossover Switch

Connect an EPIM-T to a Twisted Pair Segment as follows:

1. Insert the RJ45 connector on the twisted pair segment into the RJ45 

port on the EPIM. See Figure 4-2.

2. Check that the EPIM LNK LED is on. If the LED is off, perform each 

of the following steps until it is on:

a.

Check that the 10BASE-T device at the other end of the twisted 
pair segment is powered up.

b. Verify the RJ45 connector’s pinouts.

Position =
(not crossed over)

1. TX+
2. TX-
3. RX+
4. NC

5. NC
6. RX-
7. NC
8. NC

Position X
(crossed over)

1. RX+
2. RX-
3. TX+
4. NC

5. NC
6. TX-
7. NC
8. NC

1490_14

SEH Book  Page 3  Tuesday, March 19, 1996  4:12 PM