3Com 5124M-TPCL manual Twisted Pair Connector Specifications, RJ-45 Connector Pinouts

Note that the non-plenum type 1, 2, and 6 cables are insulated with polyethylene. The plenum type 9 cable is insulated with polyvinylchloride.

*Voice pairs in the IBM Type 2 cable cannot be used for Token Ring data transmission.

Twisted Pair Connector Specifications

The IEEE 802.3 10BASE-T standard for RJ-45 pinouts must be used, as described below. 10BASE-T uses only 2 of 4 pairs of wire: pins 1 & 2 and pins 3 & 6. If the pairs are not configured this way, the connection will not work properly.

Level 3 or higher cable should have the following pin pairings:

❑Pair 1 is pins 4 and 5 (not used)

❑Pair 2 is pins 3 and 6

❑Pair 3 is pins 1 and 2

❑Pair 4 is pins 7 and 8 (not used)

Refer to Figure A-1 for an example of the recommended TIA-568A standard pinouts for this connector and cable.

RJ-45 Connector Pinouts

Figure A-1 shows RJ-45 connector pin assignments for the 24-Port Module, Model Number 5124M-TP. This model uses MDI-X (crossed-over) wiring and only uses:

❑Pins 1 and 2 (station transmit) - 5124M-TP receive

❑Pins 3 and 6 (station receive) - 5124M-TP transmit

Specifications A - 7