Like many North American OEMs and components manufacturers, Sauer-Danfoss is navigating the functional safety landscape. The Machinery Directive (2006/42/EC) and its related standards explicitly put new, tough demands on vehicle designers to quantify the safety levels of their machine, before it is placed on the market within any European Union member country.
However, these guidelines have significant global impact as they are said to “provide a good indication of the state of the art” for the design and delivery of the safest machines practical. The application of internationally recognized state-of-the-art processes and tools for the design of safety-related control systems (SRCS) should provide confidence to any machinery manufacturer—both inside the European community as well as outside the enforcement boundaries of the directive including North America.
If there is anything certain about the future, it is that there is not just one path to compliance. As design teams begin to ask the questions—and identify potential solutions—there are three points to keep in mind.
The first is that Safety Integrity Level (SIL) certification is only part of the picture. SIL may be a familiar acronym to many; however, it has limited scope in this conversation as it originates strictly from the electronics domain. Although robust electronics can be a very critical element of machine functionality, alone it may not ensure adequate risk reduction.
Second, functional safety is a process. The optimal functional safety solution is achieved when the risk-reduction measures are seamlessly incorporated into the design of the machine’s functionality. This level of system integration requires cooperative efforts between the system integrator and the suppliers of components used in the system. Additionally, for the SRCS to be evaluated for delivered performance level, the functional safety characteristics of each component in the SRCS will need to be understood by the system integrator.
And, lastly, achieving functional safety goals relies on system solutions, not products. The Machinery Directive and its harmonized standards provide the system developer tools and guidelines to specify, develop, and validate the safety robustness of machinery for all of its functions, in all of its operating modes, and for the intended use as well as reasonably foreseeable misuse. When applied cooperatively, these international standards outline a robust design process, which can be used by machinery designers.
In summary, the revised Machinery Directive mandates that machinery manufacturers identify and reduce the potential hazards and related risks for each of the machinery’s functions, in all of its modes of operation, for both uses and misuses. Sauer-Danfoss has already been developing products that help OEMs comply with 2006/42/EC. To help our customers deliver robust machine solutions and enable them to satisfy compliance needs, we provide the necessary system and component support and information, and we work with customers to create specially designed products to facilitate compliance with the new standards, with an eye out on what to expect in the future for safety-compliant, state-of-the-art equipment.
Marc Weston, Executive Vice President and Chief Marketing Officer, Sauer-Danfoss, wrote this article for SAE Off-Highway Engineering.