Case Studies

Legacy SCADA Replacement for a Tier 1 Industrial Manufacturer

The Client

The client is a Tier 1 industrial manufacturer in North America.

Key operating realities:

  • Process knowledge is irreplaceable — decades of proprietary logic encoded in legacy systems.
  • Control systems were originally programmed in FORTRAN and C on legacy platforms from the 1980s and 1990s.
  • Uptime requirements are absolute. Outages occur only every 6–8 weeks and carry costs of several hundred thousand dollars per hour.
  • A safety-first, risk-averse culture means any modernization effort requires careful stakeholder alignment.

Problem

The client’s processing system relied on end-of-life Supervisory control and data acquisition (SCADA) and Human-Machine Interface (HMI) platforms — including a DOS-based HMI (PCWS), Indusoft Web Studio, and GE iFIX — running on legacy Windows infrastructure. The existing Level 2 control environment was no longer supportable and posed growing operational risk.

The Challenge

  • DOS-based and aging HMI software are no longer supported by vendors, creating single points of failure.
  • Legacy software code could not be maintained or extended by modern engineering staff.
  • Inability to integrate with modern workflow management, quality reporting, or enterprise data systems.
  • Severe operational constraints: testing windows limited to planned outages, with no tolerance for extended downtime.

Action

Salem Automation’s relationship with the client dates back to the mid-200s, rooted in legacy system support. Over years of consistent delivery, Salem was ultimately the only party with deep institutional knowledge of the existing environment — making us the natural choice for the project.

Salem proposed a phased modernization approach that preserved existing functionality while migrating to a modern platform. Salem replaced the legacy graphical interfaces with an Ignition-based SCADA platform on current Windows infrastructure, rewriting legacy FORTRAN code in Python and C#.

The Solution

  • Replaced DOS-based HMI and legacy SCADA with Ignition 8.x — preserving all existing operator functionality with a modernized interface.
  • Converted legacy logic to maintainable Python and C# applications.
  • Implemented Shadow Mode deployment strategy, running the new system in parallel with the existing system before cutover — maintaining 100% uptime during transition.
  • Developed comprehensive operator documentation and conducted structured on-site training aligned to go-live milestones.

Conclusion

The system eliminates reliance on end-of-life SCADA platforms and DOS-based control interfaces. The client can operate on a modern, supportable Ignition-based environment that integrates cleanly with enterprise systems and enables remote monitoring capabilities.

Salem’s phased Shadow Mode approach protected the client’s production environment throughout the transition — ensuring operational continuity while decades of proprietary process knowledge were preserved and modernized.

The Results

  • Eliminated single points of failure introduced by unsupported legacy SCADA and HMI platforms.
  • Preserved decades of proprietary process knowledge through careful code migration — zero logic lost.
  • Reduced mean time to repair (MTTR) through modern, vendor-supported hardware and software.
  • Enabled future OT/IT integration — production tracking, quality data, and enterprise reporting.
  • Protected a significant investment in legacy application logic by migrating rather than replacing.
  • Phased Shadow Mode implementation maintained 100% uptime throughout transition.

Maintain Thriving Legacy Systems with Salem Automation

We use cookies and other tracking technologies to improve your browsing experience on our website, to show you personalized content and targeted ads, to analyze our website traffic, and to understand where our visitors are coming from.