Many more of Gram Equipment’s customers want increasingly advanced solutions, as their production processes include complex systems and numerous specialized functions. Of course, every element in a system must work reliably and with a minimum amount of downtime. For example, it is constructing a very large production line for one of its most significant international customers. When finished, the plant will be able to produce 36,000 units per hour.
Meeting a King-Sized Challenge
Before implementing a Rockwell Automation safety solution two years ago, Gram Equipment often experienced problems with traditional safety systems composed of a PLC, a separate safety PLC, and a servo system. Personnel not only had to learn how to use three software programs, but also how to connect the systems so they could communicate with each other. If a plant had to be modified, this necessitated time-consuming changes to electrical documentation, as well as programming changes that could only be carried out by a few, specially trained staff. As a result, the customer often had to do more testing, with lengthy test periods being common.
Now, close cooperation between Gram Equipment and Rockwell Automation has improved this situation. In particular, changes related to safety zone control are commonly performed in agreement with an end-user during the commissioning process.
In order to simplify system complexity and usability, Gram Equipment based its control topology on an Allen-Bradley GuardLogix platform that combines standard and safety control in one platform. “This saves Gram Equipment cabling and components, as well as the time it used to take to make the systems communicate with each other,” says Bjarke S. Petersen, commercial engineer, Safety, at Rockwell Automation. Staff training is also simplified and more effective since they only need to understand one platform. “This demonstrates the strength of Rockwell Automation integrated architecture by combining control, network and safety, all in one product,” says Petersen. Combining the three functions allows more staff to modify the plant according to the customer’s wishes, faster and easier. Now employees need to learn just one software program, and electrical documentation has been simplified significantly.
The Results: Sweet!
Using GuardLogix, Gram Equipment has produced plants that can run up to 30 servo drives with integrated safety (safe-off). The system is completely scalable and fully flexible, with individual parts communicating via Ethernet/IP, a tremendous advantage when Gram Equipment works with international customers. Since the standard I/O modules run via Ethernet/IP, troubleshooting and repairs can be carried out from Denmark. This saves both Gram Equipment and its customers significant costs in time and travel. An international service and support agreement between Rockwell Automation and Gram Equipment keeps these costs to a minimum, and is an excellent example of the close cooperation between the two companies. Another plus: Rockwell Automation safety solutions are certified according to international standards, so Gram Equipment can use Rockwell Automation Safety Solutions for customers worldwide.
“Our cooperation with Rockwell Automation goes back to the mid-90s, and has developed into more than the usual customer-supplier relationship,” says John Christiansen, manager, Electrical Department, at Gram Equipment. “We work together closely, and always dialogue about the pros, cons, and costs before we choose the solution that works best for us and our customers.”
The overriding mission was to construct a new, large production line, with simplified system complexity and usability, combining standard and safety control in a single platform.
- Allen-Bradley GuardLogix Safety controller and processor with built-in safety functions
- Allen-Bradley PowerFlex drives and Kinetix servo drives with integrated safe torque off
- 1791ES CompactBlock Guard I/O
- Various safety input devices, including non-contact interlock switches, Lifeline cable pull switches, and emergency stop devices
- Ethernet I/P or DeviceNet as control networks to connect frequency transformers, controllers, I/O modules, and HMI/SCADA systems
- By combining PLC, safety, and servo functionality in one product, GuardLogix saved on cabling and components, as well as on the amount of time normally used to get different systems to communicate with each other.
- Electrical documentation was simplified.
- Reprogramming and repairs can be made anywhere in the world from Gram Equipment’s Denmark facilities, cutting costs while speeding work.
- Rockwell Automation’s safety products conform to relevant safety standards and have third-party approvals.