Will Soft PLCs Survive the Rise of Virtual PLCs?

Soft PLCs are under pressure as virtual PLCs gain ground in software-defined automation. While vPLCs offer greater scalability and flexibility, Soft PLCs still play an important role in high-precision applications. This blog explores where Soft PLCs continue to fit as the automation market evolves.

This question frequently arises in discussions with vendors about Software-Defined Automation: can Soft PLCs remain relevant as virtual PLCs continue to advance? According to Omdia data, Soft PLCs - once considered revolutionary - have struggled to scale beyond niche applications, accounting for less than 10% of PLC shipments despite being in the market for over two decades. Meanwhile, virtual PLCs (vPLCs) offer hardware independence, scalability, and dynamic capacity allocation - capabilities that Soft PLCs fail to deliver.

Vendor benchmarks confirm that vPLCs can match hardware PLCs in deterministic performance for most industrial applications. However, they still face challenges in guaranteeing determinism for sub-millisecond cycles, which are critical for motion-critical tasks. This limitation leaves room for Soft PLCs, particularly for "PLC-first" architectures where PLC runtimes are hosted on IPCs optimized for PLC applications (such as Beckhoff or Bosch Rexroth).

Unlike "IPC-first" Soft PLC platforms, which rely on general-purpose industrial PCs and are losing relevance, PLC-first platforms excel in sub-millisecond determinism and centralized management of distributed control. These capabilities not only address the gaps left by vPLCs but also offer a level of flexibility that dedicated PLC hardware struggles to match.

It seems like we’re heading toward a balance where hardware, Soft PLCs, and virtual PLCs coexist and complement each other. vPLCs might take the lead in plant-wide operations, while PLC-first platforms remain essential for machine-level tasks demanding precision and reliability - at least until vPLCs close the deterministic gap.

More details are in the analyst opinion: https://omdia.tech.informa.com/om143387/will-soft-plcs-survive-the-rise-of-virtual-plcs