“Look at motion controllers,” says Miller. “We used to have dedicated motion controllers. When customers had a motion application, they’d buy a dedicated motion controller; but, they started to say, ‘Why do I have to do that? I’m doing standard control already; why can’t motion be included?’ So we included motion; now you can’t buy a PLC where you can’t do motion control with it.” According to Miller, safety has reached that point as well.
The Rockwell Automation Kinetix® platform is a good example. Customers don’t order “safe off” as an option any longer; it’s simply included in the safety core. A customer would have to order it without “safe off” in order not to get it.
“Safety is being tightly integrated into nearly everything we do, almost every aspect of product development and technologies we implement,” notes Miller. “So the term ‘integrated architecture’ means much more than it did even five years ago, and it certainly is coming to include increased safety.”
How We Got Here
Miller believes the development and adoption of new standards such as the EN ISO 13849-1 for safety control systems is facilitating the understanding and implementation of new technologies. Typically, technology precedes the standards, and the standards have to “catch up.”
“What’s happening now is we have standards that are being generally accepted across major markets that allow for the use of new technologies,” says Miller. “Our customers are beginning to leverage the technology to meet their application requirements, understanding how to leverage it through the use of these standards.” It’s almost as if they’ve been given permission to move forward.
For example, in the past, two channels were typically used to control a safety function. If a customer needed to make sure a motor would turn off, chances are when a stop button was pressed, two channels were going through it because it was considered a critical application. So there were two devices for everything. One reason for this redundancy was the inability to quantify how good a circuit was, so a “more is better” approach was adopted: if one is good, two must be very good; if one fails, the other is still there.
Now, because safety functionality is being built into products, customers can look at the application and design using specific products with known data (e.g., failure rates, diagnostic coverage) to quantify the quality of the circuit. So only a single channel may be needed. “The standards are providing methodologies and defining requirements so that we can justify this type of design,” says Miller.
This shift can help the drive the following results:
• The safety function is improved.
• Product and systems design is driving out cost.
• The design and implementation process is simplified.
• Better diagnostics ease troubleshooting and mean less time for repair and maintenance.
• Productivity is increased.
• Sustainability is increased; designs can be implemented across a wider range of machines and applications.
According to Miller, this is a win-win situation for everyone. “I’m not saying everyone is doing this right now,” he says. “A lot of this is new: using the technology, understanding how we can use the technology, and grasping what the standards are really about. But it’s definitely moving in this direction; over the next two or three years, it is going to gather momentum as people find out how easy it is to use and the advantages to using it.”
The Real Kicker: Globalization
Miller is convinced that the globalization of business is and will continue to be the biggest driver of functional safety technology. “Consider today’s manufacturer,” he says. “He not only has a plant in North America, but another in Vietnam, a third in South Africa, and a fourth in France. So how does he implement increased safety across this global enterprise, in these different plants with different requirements?”
The globalization and harmonization of standards is leading towards the answer, because (for all sorts of reasons) a company can benefit from applying the same standard across the enterprise. There can’t be a perception that the workers in one plant site are safer than another; it makes more strategic sense to standardize safety across operations.
“Over the last year I’ve seen a dramatic increase in this understanding,” says Miller. “Technology is enabling this, and I fully expect the growth to continue as we move into the new decade.”