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PPENDIX
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| Cables and Pinouts
Twisted-Pair Cable Assignments
– 49 –
ES-3026/3026P
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ATEGORY
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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.
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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 14: 1000BASE-T MDI and MDI-X Port Pinouts
Pin
MDI Signal Name
MDI-X Signal Name
1
Bi-directional Pair A Plus (BI_DA+)
-52V power (Negative V
port
)
Bi-directional Pair B Plus (BI_DB+)
GND (Positive V
port
)
2
Bi-directional Pair A Minus (BI_DA-)
-52V 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 V
port
)
Bi-directional Pair A Plus (BI_DA+)
-52V power (Negative V
port
)
4
Bi-directional Pair C Plus (BI_DC+)
-52V power (Negative V
port
)
Bi-directional Pair D Plus (BI_DD+)
GND (Positive V
port
)
5
Bi-directional Pair C Minus (BI_DC-)
-52V 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 V
port
)
Bi-directional Pair A Minus (BI_DA-)
-52V power (Negative V
port
)
7
Bi-directional Pair D Plus (BI_DD+)
GND (Positive V
port
)
Bi-directional Pair C Plus (BI_DC+)
-52V power (Negative V
port
)
8
Bi-directional Pair D Minus (BI_DD-)
GND (Positive V
port
)
Bi-directional Pair C Minus (BI_DC-)
-52V power (Negative V
port
)
