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APPENDIX A
A.1 MDI Settings
The Medium-Dependant Interface (MDI or RJ-45) serves as the data/power interface between Ethernet elements. As such,
it has two optional connection methods, to carry the power. named Alternative A & B. Table 1 details the two power feeding
alternatives.
Pin Alternative A Alternative B
1 Vport Negative
2 Vport Negative
3 Vport Positive
4 Vport Positive
5 Vport Positive
6 Vport Positive
7 Vport Negative
8 Vport Negative
Table -1 Alternative Table
Delivering power through an RJ-45 connector’s center tap (“Phantom Feeding”) guarantees that bi-directional data flow is
maintained, regardless of a module’s power status.
A.2 Power Device Classification values
Class PD Current – Classification Period
[mA]
PD Power – Operation Period
[W]
Note
0 0 – 4 0.44 – 12.95 Default
1 9 – 12 0.44 – 3.84 Optional
2 17 -20 3.84 – 6.49 Optional
3 26 – 30 6.49 – 12.95 Optional
4 36 - 44 Future use Future use
