3.4.Connecting to networks via ethernet interface
The Ethernet communication channel allows your device to be connected to a local area network for various devices, providing a 10 Mbps/100Mbps transfer rate. Shielded 6E category twisted-pair 10/100Base-T cables with RJ-45 connectors are only supported. The maximum cable length between the Ethernet port of the device and the 10/100Base-T port on an Ethernet router/switch (without repeaters or fiber) should be 100 m (323 ft). However, in industrial application, the cable length should be kept to a minimum.
The connections are made directly from the device to an Ethernet router or switch via 8-wire twisted-pair straight-through cables. The following Ethernet settings are supported (mode selection is automatic):
- 10 Mbps half-duplex or full-duplex
- 100 Mbps half-duplex or full-duplex
The Ethernet cabling with the straight-through method is recommended as below.
PLEASE MAKE SURE YOU DO NOT MAKE AN INCORRECT CONNECTION!
|
Pin |
Pin name |
Cable color |
|
1 |
Tx+ Transmit Data |
Orange/White |
|
2 |
Tx– Transmit Data |
Orange |
|
3 |
Rx+ Receive Data |
Green/White |
|
4 |
No used by 10/100Base-T |
Blue |
|
5 |
No used by 10/100Base-T |
Blue/White |
|
6 |
Rx- Receive Data |
Green |
|
7 |
No used by 10/100Base-T |
Brown/White |
|
8 |
No used by 10/100Base-T |
Brown |
Useful Information on Ethernet Wiring:
The most common wiring for RJ-45 cables is the “straight-through” cable, which means that the pin 1 of the plug on one end is connected to the pin 1 of the plug on the other end. The straight-through RJ-45 cable is commonly used for connecting network cards with hubs on 10Base-T and 100Base-Tx networks. On network cards, the pair 1-2 serves as a transmitter, and the pair 3-6 as a receiver. The other two pairs are not used. On hubs, the pair 1-2 is the receiver and 3-6 the transmitter. It may be best to wire your cables with the same colour sequence. In this cable layout, all pins are wired one-to-one to the other side. The pins on the RJ-45 connector are assigned in pairs and every pair carries one differential signal. Each line pair has to be twisted.
In a small network with only two computers, the use of the “crossover” RJ-45 cable is necessary, where the transmitting and receiving lines on both RJ-45 connectors are cross-connected. The color-coding for the crossover RJ-45 cable has been defined in the EIA/TIA 568A standard. In the crossover cable layout, you should remember that one end is normal and the other end has the crossover configuration.
