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Introduction to CC-Link
Multi-Product, Multi-Vendor Communication System
When selecting an Open network there are several important areas to consider Speed The importance of higher communication speeds is to enable greater and more accurate manufacturing and process monitoring & control. Speed is often specified in terms of bit-rate. However, the ability to affect high-speed performance is more accurately described by throughput and response time. CC-Link technology has been optimized for speed, throughput and response. A system consisting of 64 stations and thousands of input/output points can be updated in 4 ms. There are five speed options available based on the length of wired network cable required. These range from 10 Mbps at 100 meters to 156 Kbps at 1,200 meters. However, longer distances (up to 4.3 Km) can be spanned at a 10 Mbps rate by using optical repeaters. Interoperability Interoperability is the ability of a network technology to assure that all of the devices/components of a system operate together. CC-Link technology is based on the use of an Application Specific Integrated Circuit (ASIC) available from the CC-Link Partner Association in Europe (CLPA Europe). This ASIC handles the complete data link layer and transport layer for reliable communications and assures interoperability between devices. Freely available specifications define standard connectors, cable characteristics, LED status indicators, data transmission formats, and all required networking parameters. Published device-level interface profiles and electronic CC-Link System Profile (CSP) files assure interoperability at the application layer. Conformance Testing Conformance testing through CLPA Europe ensures that devices meet the performance specifications in order to become CC-Link certified. To make it convenient for manufacturers from across the globe to have their products tested, four testing facilities have been established: one in the U.S., two in Japan, and one in Korea. Availability of Products The success of an open network is determined by the availability of automation products that support the standard technology. CC-Link is supported by over 700 association members who manufacture more than 725 CC-Link compatible products (as of January, 2006). See the Product Page for the Product listings. Openness Openness involves public and complete disclosure of detailed information of network technology. Openness is important to provide designers the knowledge, understanding and assurances required to evaluate and successfully apply the technology. The CC-Link Partner Association publishes and distributes the CC-Link specifications openly and freely to all companies who join the association. In addition, various standards organizations recognize CC-Link technology:
Reliability Reliability of a network involves immunity to electrical interference; the ability to identify errors, localize/isolate faults and allow unaffected devices to continue operating; and lastly the ability to recover from a fault condition and resume normal error-free operation without human intervention. At the physical layer, CC-Link employs the well known RS-485 signaling specification and expands on this by using three-conductor twisted shielded cable and high performance transceivers and line filters. Device conformance certification involves conducted, radiated and directly coupled electromagnetic noise. A device must be immune to this EMI and RFI to be certified. In the event that a device on the network stops communicating, CC-Link allows communication to continue with all other network devices. Upon correction of the fault, CC-Link automatically returns a disconnected device to full network operation. Another significant option to assure maximum reliability is the "Stand-by Network Master". This feature allows a Stand-by Master to automatically assume control of network communications in the event that the Primary Master station ceases to function. Determinism Determinism is the measure of predictability and repeatability. It specifies the worst-case time uncertainty for the transmission of data (such as reading inputs, setting outputs). The ability of a network to provide for stable closed-loop control of an automation system depends greatly on how deterministic its performance is. CC-Link technology utilizes a master/slave architecture. Therefore, there is no timing uncertainty due to access arbitration (unlike some other network technologies). System designers can rely on CC-Link's fast, predictable, unvarying I/O response. Ease of Implementation for Equipment Suppliers Development of a CC-Link compatible slave device is primarily a simple hardware exercise requiring no sophisticated tools. The engineering task involves integrating the CC-Link ASIC into your product. CLPA will provide your Design Engineering Team with a hardware development kit at no charge. Technical engineering assistance during your development stage is also available to your designers. And lastly, help organizing conformance testing to certify your product’s compatibility with CC-Link.
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CC-Link (Control & Communication Link) is an industrial automation network that processes both control and information data at high speed, to provide efficient, integrated factory and process automation. It is an open technology field-level network that provides high speed, deterministic communication linking a wide range of automation devices over a single cable. Today’s automation systems require an effective, integrated control system. CC-Link provides this necessary multi-vendor communication backbone. CC-Link is ideally suited for machine, cell or process control in industries ranging from semiconductors to food & beverage, automotive to pharmaceuticals, material handling to building automation. CC-Link is already the dominant technology in Asia and is growing fast in Europe and North America. This open network is supported by the worldwide CC-Link Partner Association (CLPA). The association includes hundreds of CC-Link product suppliers across the globe.
