B&R is announcing its controller redundancy system for X20 control systems, which allows the advantages of high availability to be enjoyed by smaller applications at much less cost. B&R's approach is based on standard X20 controllers that can be reconfigured at any time with features that reduce downtime using the Automation Studio software development environment. This eliminates the need for specialised redundancy controllers, which are generally very expensive due the small quantities produced. Engineering effort is reduced to declaring the PLC a redundant unit and configuring communication parameters or failure criteria.
In B&R's system, one controller provides active control, while a second controller runs in the background in standby mode. All network functions are monitored continuously so that when the time comes, the backup controller can quickly take over all of the active PLC's functions. Whichever controller becomes active always uses the same IP address as its predecessor. The switching time of the system is a mere two task cycles - so all of this takes place in a matter of a few milliseconds.
This redundancy solution is powered by the high-performance, real-time Ethernet POWERLINK communication protocol. An independent high-speed fibre optic redundancy link is used to continually synchronise all important data - the I/O image, for example - between the active and inactive controllers.
For more information about B&R's systems for controller redundancy with POWERLINK, visit www.br-automation.com.