A machinery initiative launched a year ago released its first practical results this week at the Hannover Fair. The initiative, launched in April 2011 by Sercos International, ODVA and the OPC Foundation, aimed to develop a comprehensive and open interoperability framework to help machine builders drive innovation and productivity improvements.
"We are convinced that today's great variety of automation technology requires a new conceptual approach to simplify integration of machinery in manufacturing," said Peter Lutz, managing director of Sercos International. "For this reason, we have cooperated with ODVA and the OPC Foundation in identifying topics that result in considerable technical and market synergies for users and providers."
The deliberations focused on how to implement a joint network infrastructure in which the different network protocols can coexist and the devices of different manufacturers can be operated together. This approach is intended to support mechanical engineers and users in reducing the complexity and costs of device integration in machines and systems. It also lets users base their device selections on preferred product providers.
The infrastructure required for EtherNet/IP and Sercos III includes the physics and data link layers of Ethernet, so Sercos telegrams, CIP messages and TCP/IP messages can coexist within a network without requiring additional cables. To keep the cyclical and clocked communication of Sercos III intact, the CIP messages and TCP/IP messages are transmitted in the Unified Communication Channel (UCC). This channel sits directly on the Ethernet layer without tunneling, allowing the connection of users who do not have Sercos III, but instead support a different Ethernet-based protocol.
This approach allows the combination of Sercos III devices, EtherNet/IP devices and other Ethernet devices in a joint network infrastructure in a machine or system. The existing Sercos III and EtherNet/IP specifications do not have to be modified, as the respective communication mechanisms have already been integrated in the Sercos III transmission process.
By late this year, the groups plan to create an implementation guide that describes the planning and setup of such multi-protocol networks. Initial prototypes are expected to be demonstrated at the SPS IPC Drives 2012 show in late November in Nuremberg, Germany.