PLC Systems

Allen Bradley ControlLogix PLC

Programmable Logic Controllers (PLCs) were an evolution of hardwired relay and timer based control systems, designed to ease control system design and improve system flexibility. PLCs have continued to evolve and are now the cornerstone of control and monitoring systems all over the world and in almost all sectors imaginable. PLCs no longer just sit within a control panel and carry out repetitive discrete tasks. The role that they play has also evolved; they interact with not only with their users, but also other systems and subsystems. In addition to system level interaction, PLCs now play an important data gathering and reporting role in system transparency by serving and receiving data from top end business systems.

Since our inception in 1987, Fairfields, like the PLC, has evolved too. We have a vast array of experience with a host of PLCs types, and are recognised system integrators for the major PLC suppliers in UK; Siemens, Rockwell and Schneider.

Siemens Solution Partner Logo v2Rockwell Recognised_SISchneider SI logo v2

We have a vast array of experience with a host of PLCs types, and are recognised system integrators for the major PLC suppliers in UK; Siemens, Rockwell and Schneider.

Our in-house Software Design Engineers have extensive knowledge of PLCs from all major manufacturers and can produce software in many languages, such as Ladder Logic, Statement List, Structured Text, Sequential Function Chart (Grafcet) and more.

  • Allen Bradley / Rockwell
  • Siemens
  • Schneider
  • Mitsubishi
  • Gem80
  • GE Fanuc
  • Omron
  • Square D

System Topologies

PLC system topologies can range from a simple single controller to redundant wide area distributed networks of controllers and remote I/O nodes. We are able to tailor system topology through the effective application of remote I/O and communications media and protocols in order to meet our client expectations on cost, resilience, availability and supportability.

PLC based safety systems

We work closely with our clients in order to fully determine the solution they need and in turn, the requirements that will be placed on a safety system. The standards which form the core of our safety systems design are BS EN ISO 13849-1 (replacing EN 954-1 in November 2009) and IEC 62061.

Historically, safety systems tended to be built around one or more safety relays, depending on the complexity of the system, which were entirely independent of the PLC system. Our TUV accredited engineers combine their extensive knowledge of PLC and safety systems in order to provide the most appropriate integrated safety solution, tailored to meet their needs. Increasingly, the best solution is the implementation of a failsafe PLC system. These systems combine the flexibility of PLC control with demands of the safety system. We are Rockwell and Siemens Approved Safety Systems Partners and have implemented a host of singular and distributed failsafe PLC systems, backing up our designs with full documentation and verification of the resultant performance / integrity level.

Legacy Systems and Migration

We understand that automation components, software and systems are instrumental to the success of any manufacturing company and represent a major capital investment. We are also aware that no system or technology, regardless of how innovative, can last forever. We can help our customers maintain these legacy systems until the time comes to migrate to a new system, and all of the benefits that this brings.

With our migration services, we have helped many customers to overcome product maturity without any negative impact on productivity. Our forward-looking approach is to assist, plan and prepare for their investment to meet their specific demands and security requirements in order to future-proof their systems and provide future flexibility.

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