CLPA, the CC-Link Partner Association, is rebranding CC-Link as The Non-Stop Open Network to emphasise the high availability offered by this protocol; this is achieved thanks to a number of technical features that keep the network functioning even under a range of fault conditions that might usually cause a fieldbus to cease operation. With features such as high noise immunity, 'floating master' capability, hot-swap capability and station bypass, CC-Link is claimed to be unique in offering genuine 'non-stop' functionality.
Modern manufacturing environments can be characterised by high levels of electrical noise, and this can be a real problem for fieldbus systems, often requiring the use of optical fibres to achieve noise immunity. CC-Link offers a fibre option, but the networking technology is also designed to reject a high degree of electrical noise even with standard twisted-pair copper cabling. This gives outstanding noise immunity for a low installed cost.
Another cause of loss of production can be the principal controller of the network going offline due to a loss of power, technical fault or other problem. With CC-Link's 'floating master' capability, an alternative controller on the network can immediately take over operation to maintain production with no interruptions.
Network availability is also increased through CC-Link's hot-swap capability and station bypass. The hot-swap functions and related technical features mean that stations can be removed from and returned to the network as required without causing any malfunctions. This dramatically simplifies maintenance or testing of stations with no risk of interrupting operation. Station bypass is a feature that makes future expansion of the network just as simple, by allowing network designs to include future stations without the need to actually implement them, instead bypassing them until they are actually added to the network.
The 'Non-Stop' principle extends to development, installation and maintenance of the network as well. Since configuration is parameter-based and requires no configuration files, CC-Link does not require users to learn any complex software tools, so there is no programming effort and a minimal learning curve. This helps to significantly shorten development time, getting networks up and running more quickly. Standard networks are built around simple twisted-pair twisted cables or familiar CAT-5/fibre-based Ethernet, making installation quick and simple for anyone, rather than requiring an IT network management specialist. Finally, because problems such as station errors, broken cables or disconnected cables are easily identified using the diagnostics tools, maintenance is much simpler, enabling network problems to be rectified more quickly.