Product Description:

B&R Automation's 3IF781.9 is an Ethernet interface card installed in System 2005 Controllers series racks to give the PLC base unit direct network connectivity. The board occupies an aPCI slot inside the controller backplane and appears to the CPU as an additional communication channel. This arrangement lets the controller exchange network data without relying on a separate external gateway. Within an automation cell, it serves as the physical bridge between deterministic control logic and plant-wide information layers that exchange status, recipe, or diagnostic data over standard Ethernet infrastructure.

The hardware uses the aPCI form factor, so it slides into the system chassis without external cabling for power or bus signals. A single shielded RJ45 connector carries the interface signal and supports transfer rates of 10/100 Mbit/s across the 10BASE-T/100BASE-TX physical layer. Cable runs can extend to 100 m when Category 5e or better twisted-pair media are used. Auto-MDI/MDIX is not available, so crossover wiring must be considered during installation. The module negotiates link parameters automatically with compliant switches and can operate in both full-duplex and half-duplex modes. PLC-to-IF1 galvanic isolation separates controller logic from potential network faults and reduces the risk of ground loops.

Electrical demand is low, with consumption limited to 0.66 W from the 3.3 Vdc backplane rail. Total card power does not exceed the same figure, which keeps the load on the backplane supply low. Protection is rated at IP20, so the card is intended for enclosed cabinets protected from dust ingress and spray. The front plate hosts LED indicators for transfer rate and Tx/Rx data activity, allowing traffic status to be checked without software tools. The card has 1 Ethernet port, and isolation between the backplane and network remains active regardless of link state. Autonegotiation selects the best available speed while maintaining compatibility with 10 Mbit legacy devices.