The APAX-5071 from Advantech Corp., Industrial Automation Group, Cincinnati, OH, is a Profinet coupler for its APAX Series I/O modules. The coupler's integrated 2-port Ethernet switch enables daisy-chain-style Ethernet networking between multiple distributed couplers. You can use a single coupler to interface APAX I/O for multiple distributed locations into the Profinet network; the I/O allow for the high-speed communication backplane to extend over Ethernet, allowing the I/O nodes to be connected in a line rather than a star topology.
Profinet Coupler from Advantech
Advantech Corp., Industrial Automation Group