Do we need to replace everything at once?

No. Many upgrades can be phased or staged to reduce risk and capital spend.

Which PLC brands do you support?

We specialise in Siemens, Allen Bradley, and Mitsubishi, but also work with other platforms where required.

Can obsolete systems be upgraded without downtime?

Yes, many upgrades can be planned and executed in stages to minimise or avoid downtime.

Do we need to replace everything at once?

No, systems can often be upgraded in phases, reducing risk and avoiding major operational disruption.

Which PLC brands do you support?

We support Siemens, Allen Bradley, Mitsubishi, and a wide range of legacy systems.

Can obsolete systems be upgraded without downtime?

Yes, many upgrades can be planned and executed in stages to minimise or avoid downtime.

Replace Obsolete PLC and SCADA Systems

Fault finding in a system that has become obsolete

Obsolete PLC and SCADA systems present growing risks to production, safety, and compliance. As manufacturer support disappears and spare parts become scarce, even minor failures can lead to extended downtime.

Stratos Control Systems specialises in planned PLC and SCADA replacement projects that minimise risk, disruption, and unplanned stoppages while improving long-term system reliability.

Obsolete Control System FAQs

What are obsolete control systems?

Obsolete control systems are systems that use outdated hardware or software that is no longer supported or maintained. These systems can be unreliable and difficult to repair.

Why is it important to replace outdated PLC systems?

Outdated PLC systems can lead to increased downtime, limited functionality, and difficulty sourcing replacement parts. Upgrading improves reliability and performance.

What are the risks of running legacy automation systems?

Legacy systems increase the risk of failure, reduce efficiency, and make maintenance more complex. They can also create compatibility issues with newer technologies.

Why Obsolete Control Systems Create Risk

Legacy control systems were not designed to operate indefinitely. Over time, they introduce increasing operational and business risk, particularly when knowledge is lost or systems are modified without documentation.

Replacing these systems requires careful planning to avoid introducing new failures.

Risks of Legacy PLC and SCADA Systems

No manufacturer support or spare parts
Increased failure rates and unpredictable faults
Loss of system knowledge when engineers leave
Cybersecurity and regulatory compliance risks
Difficulty integrating with modern systems

Our PLC and SCADA Upgrade Approach

We manage PLC and SCADA upgrades using a structured migration process:

Full audit of existing PLC, HMI, and SCADA systems
Migration planning using Siemens, Allen Bradley, or Mitsubishi platforms
Parallel testing to validate functionality before cutover
Staged commissioning to minimise downtime
Clear documentation and operator training

Why Planned Replacement Works Better

A planned replacement avoids emergency shutdowns, rushed installations, and undocumented fixes.

It also creates a platform that is easier to maintain, safer to operate, and supported long term.

Improve Visibility and Long-Term Supportability

Modern control systems improve visibility, diagnostics, and maintainability.

Replacing obsolete PLC and SCADA systems enables:

Clear system visibility and monitoring
Improved diagnostics and alarm handling
Better integration with modern platforms
Long-term vendor support and scalability

Who This Is For

This approach is typically used by:

Engineering Managers managing ageing control systems
Maintenance Managers dealing with obsolete PLC hardware
Operations teams experiencing increased downtime risk
Businesses planning phased system modernisation

Speak to an Automation Engineer

Frequently Asked Questions

Plan a control system upgrade

Replace obsolete PLC and SCADA systems safely with minimal disruption.