Okay, so hooking one’s safety instrumented system (SIS) directly to the public internet is clearly not a recommended best practice. But properly applied, many of the digital technologies that underlie the broader Industrial Internet of Things (IIoT) movement can streamline SIS engineering tasks, improve system performance and in the end contribute to higher plant profitability.
At this week’s Foxboro User Group conference in San Antonio, Chris Stogner, Triconex offer manager, Schneider Electric, explained how technologies such as secure (and appropriate) connectivity, digital emulation and big data analytics are allowing safety systems to perform better as well as increasing the productivity and effectiveness of those engineers responsible for their design and support.
“The IIoT isn’t necessarily about connecting to the internet,” Stogner explained. "Rather it’s about leveraging connectivity and other digital technologies to improve personnel productivity and system performance. And for an SIS, that performance is measured not only by safety, but also by the availability or uptime of the process in question. The SIS must respond when something goes wrong to prevent equipment damage, injury or loss of life. But the best SIS solutions also have the resilience to resist spurious trips that negatively impact production and profitability.
“Both safety and profit are critical to business success,” Stogner said.
Safer plants make more money
Stogner cited a recent Center for Chemical Process Safety report indicating that companies with top notch safety performance practices also are 5% more profitable. “Their operations are not only safer, they’re more reliable, they have less downtime and they even have lower insurance rates—all of which have a direct impact on profitability.”
“These new technologies can make you safer and more secure,” Stogner added. “Each new connection may add some risk, but the real question is: Does that connectivity add new value that outweighs the risk?”
Connectivity with the basic process control system (BPCS) in particular remains a controversial practice in some circles due to common-cause-failure concerns. So to address every organization’s own risk-to-benefit calculations, Schneider offers three different three digital connectivity options: integrated (with its own EcoStruxure Foxboro DCS), interfaced or entirely separate.
The choice not to integrate with the BPCS, however, does not preclude the deployment of SIS diagnostics and preventive maintenance alerts that can be independently communicated to responsible personnel. Such alerts can help to head off downtime before it happens. “Safety systems are moving beyond their traditional reactive role, to a more proactive role,” Stogner said.
Maintenance Advisor is among those Schneider digital solutions that can help bird-dog process and system issues before they become upsets or shutdowns. The condition-based maintenance and decision-support tool monitors asset health in real time to provide early warning of impending failures—complete with recommended corrective actions.
More productive engineering and analysis
In the engineering realm, Schneider’s latest generation of safety system, the Tricon CX, works with the company’s Universal I/O and off-the-shelf Safety Intelligent Enclosures. This means that when ordering your next SIS you may only need know your total I/O count. “We can ship now, you can design later,” Stogner said.
And with the company’s unique, TÜV-certified Triconex Safety Validator solution, application safety logic can be tested in advance of physical deployment on an emulated version of the controller platform. Consistent with Schneider’s FLEX (for flexible, lean execution) project methodology, this approach has delivered outsized returns for users. One company reported an 85% time savings—and earlier start-up by four days—in the course of a site-acceptance test. Another trimmed 216 man-days of labor from factory acceptance test (FAT) procedures.
Other Schneider digital solutions designed to ease SIS engineering tasks include Field Device Expert, which provides for rapid, intelligent digital commissioning of HART field instruments. Further, SIS versions of the company’s System Advisor and System Auditor solutions provide enhanced configuration documentation, change tracking and I/O management for Triconex safety systems.
Post-incident investigation has also been significantly streamlined with the addition of Trip Analyzer functionality to the company’s SIF Manager solution. Essentially big data analytics applied to safety system events, this solution dramatically reduces the time required to gather data and perform root-cause analysis on trips—a time-consuming tasks required by a significant and growing number of regulatory authorities.