Story 1Processonline
Closing the gap: rethinking the middle ground for logic solvers in safety instrumented systems
Signal strongSource-grounded
What happened
Process Online outlines a growing class of multifunction safety logic solvers that sit between single-loop relays and full safety PLCs. These devices are marketed with IEC 61508 certification and support voting architectures, making them operationally useful for distributed safety instrumented functions; watch whether suppliers provide FAT/SAT and commissioning artifacts at scale
Why the category manager should care
Treat these devices as viable alternatives to full safety PLCs for scattered SIFs, but require commissioning and recorded acceptance up front because costs and risks move into engineering and lifecycle work
Key facts
- Multifunction logic solvers handle multiple I/O channels
- Support for voting architectures such as 1oo2 and 2oo3
- Devices typically offered with IEC 61508 certification for SIL-capable use