User guide

A PPENDIX D | Cables and Pinouts
Twisted-Pair Cable Assignments
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STRAIGHT-THROUGH
WIRING
If the twisted-pair cable is to join two ports and only one of the ports has
an internal crossover (MDI-X), the two pairs of wires must be straight-
through. (When auto-negotiation is enabled for any RJ-45 port on this
switch, you can use either straight-through or crossover cable to connect
to any device type.)
You must connect all four wire pairs as shown in the following diagram to
support Gigabit Ethernet connections.
Figure 68: Straight Through Wiring
Table 31: 10/100BASE-TX MDI and MDI-X Port Pinouts
PIN
MDI Signal Name
a
a. The “+” and “-” signs represent the polarity of the wires that make up each wire
pair.
MDI-X Signal Name
1 Transmit Data plus (TD+)
-48V power (Negative V
port
)
Receive Data plus (RD+)
GND (Positive V
port
)
2 Transmit Data minus (TD-)
-48V power (Negative V
port
)
Receive Data minus (RD-)
GND (Positive V
port
)
3 Receive Data plus (RD+)
GND (Positive Vport)
Transmit Data plus (TD+)
-48V power (Negative Vport)
4-48V power (Negative V
port
) GND (Positive V
port
)
5-48V power (Negative V
port
) GND (Positive V
port
)
6 Receive Data minus (RD-)
GND (Positive Vport)
Transmit Data minus (TD-)
-48V power (Negative Vport)
7 GND (Positive V
port
) -48V power (Negative V
port
)
8 GND (Positive V
port
) -48V power (Negative V
port
)
White/Orange Stripe
Orange
White/Green Stripe
Green
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
EIA/TIA 568B RJ-45 Wiring Standard
10/100BASE-TX Straight-through Cable
End A
End B
Blue
White/Blue Stripe
Brown
White/Brown Stripe