Industrial Ethernet portfolio now includes fault-tolerant redundancy option

30 January 2012

Siemens Industry Automation and Drive Technologies has expanded its industrial network products range with a fault-tolerant system for smooth and delay-free redundancy in industrial Ethernet networks. The new Scalance X-200RNA (Redundant Network Access) network access points are suitable for applications requiring particularly high fault tolerance. In addition to the Scalance hardware, Siemens also offers the Softnet-IE RNA software package enabling PCs to be connected to parallel networks.

The redundant system is based on the Parallel Redundancy Protocol (PRP) in accordance with the IEC 62439-3 standard. The X-200RNA Scalance access points connect one or two network segments or data terminals without PRP functionality over two parallel networks without delay. An access point duplicates the transmitter's message frame and feeds a copy into each of the connected networks.

The two LANs can have different structures – star, ring or tree. At the receiver end, the second access point passes on the first message frame which arrives to the addressees. The message frame which arrives subsequently from the other LAN is discarded. The two separate networks and the PRP procedure guarantee secure and punctual transmission. A reconfiguration time, as required by other redundancy procedures using just one physical network, is therefore superfluous.

The product is offered in a plastic enclosure with four electric RJ45 ports, and in a metal enclosure with two electric ports and two electric/optical combined ports for SFP (Small Form-Factor Pluggable) transceivers and wide-range power supplies.

The Softnet-IE RNA software package can be used for linking PCs at low cost into redundant, parallel network topologies based on PRP without additional programming overheads. Using the Siemens software, a computer can establish the same smooth redundancy connection over two LAN networks as the Scalance X-200RNA network access points.