4-14
Since an Ethernet cable needs to pass through a waterproof cover for waterproof purpose (an Ethernet
cable with an RJ-45 connector is unable to pass through), you need to prepare an Ethernet cable
connector on site. Usually a category-5 or enhanced category-5 twisted pair cable is adopted. Figure
4-18 shows an Ethernet cable connector.
Figure 4-18
Ethernet cable connector
Ethernet cables fall into straight-through Ethernet cables and crossover Ethernet cables.
z
Straight-through Ethernet cable: The wires of a twisted pair cable are crimped in the same
sequence in the RJ-45 connectors at both ends. A straight-through cable is used to connect a
terminal device (such as PC or router) to a hub or LAN Switch.
z
Crossover Ethernet cable: The wires of a twisted pair cable are crimped in different sequences in
the RJ-45 connectors at both ends. A crossover Ethernet cable is used to connect a terminal
device (such as PC or router) to another terminal device. You can make such a cable by yourself.
Table 4-1
RJ-45 straight-through Ethernet cable pinouts
Pin of RJ-45
connector
Signal
Category-5 twisted pair
cable
Signal direction
Pin of RJ-45
connector
1 Tx+
White
(orange)
Æ
1
2 Tx-
Orange
Æ
2
3 Rx+
White
(green)
Å
3
4 —
Blue
— 4
5 —
White
(blue)
— 5
6 Rx-
Green
Å
6
7 —
White
(brown)
— 7
8 —
Brown
— 8
Table 4-2
RJ-45 crossover Ethernet cable pinouts
Pin of RJ-45
connector
Signal
Category-5 twisted pair
cable
Signal direction
Pin of RJ-45
connector
1 Tx+
White
(orange)
Æ
3
2 Tx-
Orange
Æ
6
