Integrated Safety Instrumented Systems: Transforming Process Safety

Over the past few decades, various control disciplines like process, batch, motion and discrete control have been consolidated into a single, common automation architecture. This integration has reduced disparate systems and interfaces in process operations, making jobs easier.

However, one technology that has remained elusive from this common automation architecture has been safety instrumented systems (SIS) — at least until now.

The recent introduction of integrated SIS brings this critical process-safety system onto the same platform as the base process control system (BPCS). Now, the two systems can be programmed, configured, operated and maintained together, within a common automation architecture.

Process operators that embrace this new approach to SIS can realize new efficiencies in their operations and transform how they manage process safety. Here’s how.

Easing equipment configuration and deployment

Process industry safety standards historically required safety systems to operate on a platform separate from process control. However, this trend is shifting to allow fully integrated systems that can handle both the BPCS and SIS.

This integration optimizes workflows for engineers because they now only need to learn and know one platform to manage the BPCS and the safety system. Whether engineers are building a process or safety loop, the mechanics will be the same. And because the software environment is common for both SIS or BPCS, configuration and programming work is simplified and can be done more quickly.

Historically, creating a common HMI display from disparate BPCS and SIS could be difficult because it required mapping data from two systems that used different logic. But when BPCS and SIS data come from the same platform and use a common logic, building that common HMI view becomes easier and more intuitive.

Integrated SIS can also optimize and accelerate commissioning. The team doing this work can be smaller and more efficient because a common architecture avoids the need for multiple engineers with specialized knowledge of the BCPS and SIS platforms.

Simplifying plant floor operations

A common platform for the BPCS and SIS eases the work of plant floor teams just like it does for engineering teams. Production and maintenance staff now only need to learn one set of hardware and software to operate, monitor and maintain both systems.

Liz Bahl Prosak, commercial portfolio manager at Rockwell Automation.

Inventories can also be streamlined and costs can be reduced because maintenance teams now only need to stock spare parts for one platform instead of two. Likewise, if a maintenance team needs vendor support, they only have one number to call for both their BPCS and SIS.

Another way integrated SIS can benefit plant teams is by providing modernized features and capabilities not available in traditional SISs. New integrated SIS solutions, for instance, offer features like redundancy system updates. This allows SIS controllers, communication modules and redundancy modules to be updated while they’re running. Updates no longer need to be scheduled during planned downtime.

Access to disparate data

Bringing together disparate systems into a unified architecture also brings together disparate data sources. This allows process operators to combine and contextualize a wider range of data to create a more complete view of what’s happening in their operations.

At a minimum, having BPCS and SIS data available together from a common platform can make it easier to give operators visibility into what’s happening in production.

Kris Dornan, marketing manager for large controllers at Rockwell Automation.

Historically, creating a common HMI display from disparate BPCS and SIS could be difficult because it required mapping data from two systems that used different logic. But when BPCS and SIS data come from the same platform and use a common logic, building that common HMI view becomes easier and more intuitive.

Bringing BPCS and SIS data together can also unlock new insights for plant-floor staff. It could, for instance, provide visibility into how close a process is to the setpoints that trigger the SIS to take over. This could help staff more proactively monitor and address issues before they lead to shutdowns.

While integrated SIS offerings are new to the market, they already have a wide range of use cases. They can be used in general process safety applications and hybrid applications that require both machine and process safety.

As the applications for integrated SIS grow, more process operators will be able to finally remove SIS as a silo in their operations, making equipment easier to deploy and both uptime and safety easier to maintain.

Liz Bahl Prosak is commercial portfolio manager and Kris Dornan is marketing manager for large controllers at Rockwell Automation.