Edge-Core EAP8518 - Page 253

A PPENDIX D | Cables and Pinouts
Twisted-Pair Cable Assignments
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CABLE TESTING FOR EXISTING CATEGORY 5 CABLE
Installed Category 5 cabling must pass tests for Attenuation, Near-End
Crosstalk (NEXT), and Far-End Crosstalk (FEXT). This cable testing
information is specified in the ANSI/TIA/EIA-TSB-67 standard. Additionally,
cables must also pass test parameters for Return Loss and Equal-Level Far-
End Crosstalk (ELFEXT). These tests are specified in the ANSI/TIA/EIA-
TSB-95 Bulletin, “The Additional Transmission Performance Guidelines for
100 Ohm 4-Pair Category 5 Cabling.”
Note that when testing your cable installation, be sure to include all patch
cables between switches and end devices.
ADJUSTING EXISTING CATEGORY 5 CABLING TO RUN 1000BASE-T
If your existing Category 5 installation does not meet one of the test
parameters for 1000BASE-T, there are basically three measures that can be
applied to try and correct the problem:
1. Replace any Category 5 patch cables with high-performance Category
5e or Category 6 cables.
2. Reduce the number of connectors used in the link.
3. Reconnect some of the connectors in the link.
Table 32: 1000BASE-T MDI and MDI-X Port Pinouts
Pin MDI Signal Name MDI-X Signal Name
1 Bi-directional Pair A Plus (BI_DA+)
-48V power (Negative V
port
)
Bi-directional Pair B Plus (BI_DB+)
GND (Positive V
port
)
2 Bi-directional Pair A Minus (BI_DA-)
-48V power (Negative V
port
)
Bi-directional Pair B Minus (BI_DB-)
GND (Positive V
port
)
3 Bi-directional Pair B Plus (BI_DB+)
GND (Positive Vport)
Bi-directional Pair A Plus (BI_DA+)
-48V power (Negative Vport)
4 Bi-directional Pair C Plus (BI_DC+)
-48V power (Negative V
port
)
Bi-directional Pair D Plus (BI_DD+)
GND (Positive V
port
)
5 Bi-directional Pair C Minus (BI_DC-)
-48V power (Negative V
port
)
Bi-directional Pair D Minus (BI_DD-)
GND (Positive V
port
)
6 Bi-directional Pair B Minus (BI_DB-)
GND (Positive Vport)
Bi-directional Pair A Minus (BI_DA-)
-48V power (Negative Vport)
7 Bi-directional Pair D Plus (BI_DD+)
GND (Positive V
port
)
Bi-directional Pair C Plus (BI_DC+)
-48V power (Negative V
port
)
8 Bi-directional Pair D Minus (BI_DD-)
GND (Positive V
port
)
Bi-directional Pair C Minus (BI_DC-)
-48V power (Negative V
port
)