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Legacy control system upgrades and migration

Obsolete PLCs, SCADA, HMI and drive systems are a risk that's easy to ignore - until something fails. 

A carefully planned migration strategy protects your production, minimises downtime and lets you align costs to your budget cycle.

Legacy control system upgrades and migration

What's included with every legacy system upgrade:

  • Full assessment of your existing legacy system
  • Planned migration strategy tailored to your production schedule
  • Upgrade of PLC, SCADA, HMI and drive systems
  • Costs structured to align with your annual budget cycle
  • Minimal interruption to production during migration
  • Like-for-like replacement or full system redesign where beneficial
  • In-house build, programming and testing before site deployment
  • On-site installation, commissioning and handover

About our legacy system upgrade service

Legacy PLCs, SCADA, HMI and drive systems often go unnoticed until they fail - at which point the cost and disruption of an unplanned outage far outweighs what a managed migration would have cost. We upgrade many systems every year, working with customers to plan migrations in advance, structure costs to fit budget cycles, and carry out the work with minimal interruption to production. We also respond when the worst happens and a critical system has failed beyond repair.

Why Nivalis?

Why Nivalis?

We understand the reluctance to touch a system that's still running - even when it's obsolete. The concerns about production disruption and upfront cost are real, and we don't dismiss them. What we offer is a pragmatic, planned approach - an honest assessment of your risk, a migration strategy that works around your schedule, and costs that can be spread across budget cycles. We've helped many businesses move from ageing legacy systems to modern platforms without the unplanned failure they were trying to avoid.

Siemens S5 migration

Planned upgrade from obsolete Siemens S5 systems to current TIA Portal S7 platforms.

Allen-Bradley SLC 500

Migration from legacy SLC 500 and PLC5 systems to current CompactLogix or ControlLogix.

Legacy SCADA & HMI

Upgrade of end-of-life SCADA and HMI platforms to current supported software.

Drive system upgrades

Replacement of obsolete variable speed and servo drive systems with current technology.

Budget-aligned planning

Migration costs structured to align with your annual capital expenditure cycle.

Emergency response

Critical system failed beyond repair? We respond quickly to get production running again.

Our process

  • 01: Assess

    Review existing system, identify risks and define scope

  • 02: Plan

    Migration strategy aligned to your production schedule and budget

  • 03: Build

    New system built and programmed in-house

  • 04: Test

    Full testing against existing system before site deployment

  • 05: Migrate

    Controlled on-site switchover with minimal production interruption

Don't wait for something to fail

Don't wait for something to fail

Legacy control systems are one of the most commonly overlooked risks in industrial operations. A Siemens S5 or Allen-Bradley SLC 500 that has run without issue for twenty years feels like a solved problem - until it isn't. Spare parts become unavailable, support contracts lapse, and the engineers who originally built the system have long since moved on. When failure eventually comes, it comes without warning and at the worst possible time.

The good news is that a carefully planned migration changes the equation entirely. Working around your production schedule, we develop a migration strategy that moves you from an obsolete system to a modern, supported platform with minimal downtime and costs that can be spread to fit your budget. We carry out the full upgrade in-house - new hardware, new software, fully tested - before a controlled switchover on site.

If you have legacy PLC, SCADA, HMI or drive systems that haven't been reviewed recently, talk to us. We'll give you an honest assessment of your risk and a clear view of what a migration would involve - no obligation, no pressure.

Related services

PLC Software

Custom programming across all major platforms

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SCADA and HMI Software

Visualisation and control of your plant and process

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Discuss your legacy control system project

No-obligation conversation. We'll tell you honestly if we're the right fit.