NS3552-8P-2S-V2 User Manual  491  
Appendix A  
Networking connection  
PoE RJ45 port pin assignments 
 
 
Pin Number  RJ45 Power Assignment 
1  Power + 
2  Power + 
3  Power - 
6  Power - 
RJ45 port pin assignments – 1000Mbps, 1000BASE-T 
 
  MDI  MDI-X 
  BI_DA+  BI_DB+ 
  BI_DA-  BI_DB- 
  BI_DB+  BI_DA+ 
  BI_DC+  BI_DD+ 
  BI_DC-  BI_DD- 
  BI_DB-  BI_DA- 
  BI_DD+  BI_DC+ 
  BI_DD-  BI_DC- 
Implicit implementation of the crossover function within a twisted-pair cable, or at a 
wiring panel, while not expressly forbidden, is beyond the scope of this standard. 
10/100Mbps, 10/100BASE-TX 
When connecting the industrial managed switch to another Fast Ethernet switch, a 
bridge, or a hub, a straight or crossover cable is necessary. Each port of the industrial 
managed switch supports auto-MDI (Media Dependent Interface)/MDI-X (Media 
Dependent Interface Cross) detection. This makes it possible to directly connect the 
industrial managed switch to any Ethernet device without making a crossover cable. 
The following table and diagram show the standard RJ45 receptacle/ connector and 
their pin assignments.