Automation Vendors - Open where they are weak?

OT BRIEF: Here we analyze the reasons why automation vendors position where they are open in their offerings. Contact us for a comprehensive vendor comparison

A Rule Hiding in Plain Sight

Every major automation vendor now leads with openness. Open ecosystems, open standards, open architectures, open automation: the vocabulary is uniform across the tier, from the largest DCS incumbent to the newest software entrant. And on the surface the claims are individually true. The controllers do carry OPC UA servers. The protocols are administered by member organizations. The new HMI platforms are standards-first. The press releases do not lie.

They position themselves relative to openness on their weaknesses rather than their strengths. Arrange each vendor’s openness initiatives next to a map of its installed base, and a rule appears that holds across every major supplier in the industry: openness varies inversely with incumbency. Where a vendor’s franchise is strong, its interfaces stay closed, its engineering artifacts stay proprietary, and its ecosystem economics stay captive. Where its franchise is weak — the layer it lost, the market it never won, the architecture it fears — that is where the open initiative lives. The pattern is consistent enough to be used as an instrument: an openness announcement, read correctly, is a disclosure of competitive position more candid than anything in the annual report.

Four Readings on the major vendors

The edge opens; the project format does not

Siemens is the industry’s loudest advocate of OPC UA, a founding force behind its field-level extensions, and the shipper of an OPC UA server across its current controller lines — as a licensed per-CPU runtime option, not a bundled default. It is also the vendor whose engineering moat has never been the wire. Controller communications in current firmware are TLS-secured and standards-visible; the TIA Portal project format, the library ecosystem built on it, and the certification economics of the Profinet device ecosystem are none of those things, and they are where two decades of customer engineering investment actually live. The openness is real, and it is positioned with precision: at the boundaries of the franchise, running parallel to the moat. This moat comes in the form of sunk cost in the TIA Portal projects and Profinet ecosystem.

The HMI opens; the controller opens at the margin

Rockwell Automation launched FactoryTalk Optix as a new-generation visualization platform: web-native, OPC-UA-first, portable across targets, openly priced. It is a genuinely modern product. Enterprise-scale visualization is also the layer where the incumbent offering had aged hardest against a decade of disruption from server-licensed, unlimited-tag SCADA economics — the weak flank, opened boldly. The controller franchise, the layer that wins, with the deepest device ecosystem and integrator base in North America, opened later and narrower. Embedded OPC UA arrived with the v36 firmware release in the premier ControlLogix and CompactLogix lines, after years of addressing the requirement through gateway cards and modules. But the implementation is bounded on every axis that matters: disabled by default and enabled through a message instruction rather than configuration; available only via the embedded Ethernet port; unsupported under ControlLogix 5580 redundancy at that release; and node-capped tightly enough that lower-tier controllers in the family expose no usable nodes at all, while on those that do, a handful of instruction-heavy user-defined types exhausts the budget. The practical envelope is controller-to-controller exchange, not serving an HMI or a historian. The direction of travel is correct, and the premier lines are the right place to start.

Openness that runs one direction

Emerson’s Boundless Automation frames a vision of data moving freely across the enterprise, and the portfolio has real open components at the data layer. But the flagship openness artifact at the control layer runs in exactly one direction: DeltaV IO.Connect allows DeltaV control to take over a competitor’s installed I/O — easing migration into the ecosystem, with the vendor’s own literature describing the subsequent transition to DeltaV I/O as opportunistic and over time — while no reciprocal path exists out of it. An interface that opens the way in is an acquisition tool; an interface that opens the way out is a repricing of the installed base to zero. No incumbent ships the second kind voluntarily, and the direction an ‘open’ interface runs is therefore one of the most information-dense facts a buyer can check.

The boldest opening — at the weakest layer

Schneider Electric has made the industry’s most radical architectural commitment to openness: EcoStruxure Automation Expert, built on IEC 61499, with control logic portable across hardware — backed by a multi-vendor organization created to make runtime portability an industry norm rather than a product feature, and now demonstrated by deployment of the same applications onto a competitor’s controller hardware. It is the correct direction of travel, and this series has said so. It is also positioned exactly where the inversion rule predicts: at the PLC layer, where Schneider’s franchise trails the two discrete leaders. One layer up, at the historian — the strongest single software franchise any automation major owns — the commercial architecture has moved the other way: current releases of the industry’s de facto time-series standard are now available only by subscription, with perpetual-license customers maintained on a legacy patch branch, excluded from new development.

Why the Inversion Is Structural

None of this requires cynicism to explain, and none of it is unique to industrial automation. An installed base in OT is an annuity: engineering artifacts, trained staff, spares inventories, certified integrations, and validated safety cases all accrue to the incumbent interface, and the switching cost they represent is the rent the incumbent collects. Opening the strong franchise converts that rent to zero. Opening the weak flank costs nothing — there is no rent to lose — and buys three things: a wedge into the rival’s estate, a claim on the emerging standard before someone else defines it, and an openness narrative that halos over the closed core.