Chances are, you can point to a few key processes in your industry where timing is especially critical – where precise execution is essential to the quality and quantity of your output. When every microsecond matters, even the most powerful PLC can be pushed to its limits. B&R's reACTION Technology delivers ultrafast response times with the low cost and effort of off-the-shelf hardware and software.
Bottling processes are notoriously time critical. To maximize quality and throughput, valves and sensors must be tightly synchronized in real time. Similar requirements are encountered when applying adhesive dots to packaging, sorting items in a recycling plant or laser-cutting sheet metal. "Historically, the short response times needed in such applications have required the use of special hardware," reports Andreas Hager, B&R's product manager for control systems.
With reACTION Technology, B&R proves there is another way. Programs developed using the Function Block Diagram editor in the Automation Studio engineering environment are executed directly on I/O modules from B&R's X20 and X67 series. This transforms the I/O modules into "mini controllers" able to handle certain processes independently and distribute the computational load across multiple systems.
Outsourcing time-critical programs to I/O modules makes it possible to achieve ultra short response times down to 1 µs. With a reduced load on the PLC, it often becomes possible to scale down to a less powerful alternative. Importantly: this also decouples the response time from the cycle time of the fieldbus. Optimizing cycle times can bring a substantial boost in productivity. The attractive price of B&R's reACTION modules unlocks the benefits of ultrafast automation for a broader range of machines than ever before.
Like any other control program, a reACTION program can be created in Automation Studio using function blocks according to IEC 61131-3. It is saved centrally on the PLC, transferred to one or more I/O modules as required and then stored there. Of course, different products require different recipes, so it is also possible to load new programs onto the modules during operation, and saved programs can be copied to other modules at any time. The selection of reACTION function blocks is growing all the time, and new blocks can be added in the field simply by upgrading the firmware. Users can also create their own function blocks based on the ones provided, and use them to bring clarity to complex programs. Developers who already work with Automation Studio do not need any additional training.
Available with up to eight freely configurable analog or digital inputs and outputs, reACTION modules operate as a small stand-alone controller. "They process input signals, run their program and generate output data," adds Hager. When reading digital inputs, a reACTION program can determine not only the current state at the start of the cycle, but also the exact switchover point with a resolution of 20 ns. In addition, the modules can use POWERLINK, X2X or X2X+ to communicate with any other X20 and X67 modules and of course also send data to the controller. Based on the needs of their application, users can choose between IP20-rated modules for control cabinet installation and IP67-rated variants for direct installation in the field.
B&R's intelligent I/O modules pay dividends in many applications. A particularly good example is offered by one B&R customer's printing machine for packaging materials. Andreas Hager explains: "It currently runs at a web speed of 600 m/min, but there are already plans for a faster new version. So they needed enough reserves in the automation solution to handle those higher speeds down the road."
Printing the packaging material is the first step in the process. Then, a serial number is laser marked onto a specific location on each package. A sensor detects the position where the serial number should be placed and generates a digital signal. An X20 reACTION module evaluates that signal and generates a digital output signal for the laser marker. To minimize errors when the machine is accelerating, the sensor and laser marker need to be positioned as closely together as possible. Due to the construction of the machine, the minimum distance between them is 55 mm. The sensor for detecting registration marks is connected to Channel 1 of the I/O module, the starting signal for the laser marker to Channel 3.
The parameters for the reACTION module are calculated based on the current web speed. After the sensor reads the position, the following times elapse before marking can begin: 1 ms dead time in the sensor, 0.5 ms filter time (shorter signals are not permitted be processed), 0.04 ms processing time by the reACTION task (2x reACTION cycle time because in the worst case the signal is received shortly after the scan), and 2 ms dead time in the laser marking device. Thus, the fastest possible response time is 3.54 ms.
At the given distance of 55 mm, this results in the following maximum speed: 55 mm / 3.54 ms = 15.5 m/s = 932 m/min. In other words: the printer has the potential to run up to 55% faster than its current speed of 600 m/min – so nothing stands in the way of a new machine generation with higher web speed and higher throughput. With stories like this, B&R customers confirm time and again that premium automation performance can be achieved with the low cost and effort of off-the-shelf hardware and software.
