Enterasys Networks V2H124-24P - Manual (Page 54)

Cables
B-2
B
Table B-1. 10/100BASE-TX MDI and MDI-X Port Pinouts
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.)
Figure B-2. Straight-through Wiring
Crossover Wiring
If the twisted-pair cable is to join two ports and either both ports are labeled with an
“X” (MDI-X) or neither port is labeled with an “X” (MDI), a crossover must be
implemented in the wiring. (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.)
Pin MDI-X Signal Name MDI Signal Name
1 Receive Data plus (RD+) Transmit Data plus (TD+)
2 Receive Data minus (RD-) Transmit Data minus (TD-)
3 Transmit Data plus (TD+) Receive Data plus (RD+)
4 GND (Positive V
port
) GND (Positive V
port
)
5 GND (Positive V
port
) GND (Positive V
port
)
6 Transmit Data minus (TD-) Receive Data minus (RD-)
7 -48V feeding power (Negative V
port
) -48V feeding power (Negative V
port
)
8 -48V feeding power (Negative V
port
) -48V feeding power (Negative V
port
)
Note: The “+” and “-” signs represent the polarity of the wires that make up each wire pair.
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
White/Brown Stripe
Brown Stripe