Drives & Controls Magazine November/December 2022

33 November/December 2022 CONTROLLERS AND SOFTWARE n PLC and PAC sales rebound from Covid A fter a sudden downturn in the PLC (programmable logic controller) market during 2020 as a result of the Covid pandemic, the market recovered quickly by the end of 2021, according to a new report from the ARC Advisory Group. It says that by the end of last year, most industries had recovered to their 2019 levels, while others – such as the automotive sector – should do so by the end of 2022. The PLCmarket proved its resilience during 2021 as the world learned to cope with the effects of Covid and demand returned. Most PLC suppliers reported robust growth last year, and this has extended into 2022. Over the past decade, PLCs have gained in speed and added new functions, allowing some users to switch to smaller PLCs. This is especially popular with cost-conscious machine-builders, and is changing the dynamics of the market. Thanks to the Industrial Internet of Things (IIoT), future automation architectures will support modular machines and distributed control, fulfilling a dream that dates back to the 1990s. In the process sector, consortia are developing specifications for machine type packages (MTPs) that support standardisation of modular architectures, most of which are based on PLCs. The success of standardised modular architectures is likely to spill over to other industries when the business benefits become clear, ARC predicts. The industrial edge – located between traditional, closed automation systems and the modern, connected world – is quickly becoming a“safe space”for industrial users to connect their OT systems to the IT world. It is also where mission-critical apps and even virtual PLCs will be hosted in future automation architectures. End-users can experiment and discover practical applications for the IIoT by using edge devices to add new functions, such as machine analytics, to existing automation systems, the report suggests. Machine-builders can differentiate their offerings by adding new functions, even before customers start demanding them. The key for both is to get ahead of the demand curve for the next generation of industrial controls. The cloudmay be located far away from the edge, but the two domains work hand-in-hand. Most non-time-critical industrial software will in future be hosted in the cloud, giving supervisory software and analytics apps simple, secure access to data frommultiple plants. The edge is where the data is collected as it is generated. Apps at the edge react quickly and locally, while apps in the cloud collect and evaluate large amounts of data frommany sources. A reliable edge-to-cloud connection is important for daily operations, but should not become a critical link for mission-critical operations, ARC suggests. As users gain experience of both domains, they will learn which apps to run at the edge, and which to run in the cloud. According to the report, the influence of commercial IT on automation systems is growing every year. Automation architectures are becomingmore IT-like, and connectivity is improving thanks to smart devices and open standards. Today, PLCs can be virtualised and consolidated on servers with other plant software where they can run in an environment that is better managed than on the shop floor. ARC suggests that machines may soon be run by networks of connected smart devices and systems that greatly improve access to machine and process data. But the road to the IIoT will be more of an evolution than a revolution, it adds. The report identifies several trends, including: n communications are becoming increasingly standardised and universal; n modularity is adding flexibility and scalability; n everything is becoming software-defined; n increasing IO counts are allowingmore data to be gathered; and n cloud links are becomingmore common. “The IIoT is changing how industrial processes are controlled andmonitored, but PLCs are growing with, and adapting to, the new challenges rather than being replaced by alternative technologies,”says ARC research director, David Humphrey, who is also the key author of ARC's Programmable Logic Controllers and PLC-based Programmable Automation ControllersMarket report. “Despite threats from contemporary technologies, the classic PLC continues to be the preferred choice amongmachine-builders and end-users to control industrial machinery and processes – and increasingly in infrastructure applications,”Humphrey reports. “Based on established industrial technology, PLCs are valued for their speed, repeatability, reliability, and ease of deployment and maintenance. These characteristics are difficult to achieve with other technologies.” n The market for PLCs and PACs (programmable automation controllers) has bounced back since Covid, according to a new report that examines how control technologies are likely to evolve in the years ahead.