- MCS was tasked with replacing an aging Allen-Bradley PLC-5®-based control architecture, which controlled two steam turbines and three furnaces, with a more up-to-date solution without changing the footprint of the installation and using the existing cabling and wiring infrastructure
- Allen-Bradley ControlLogix Programmable Automation Controller (PAC)
- Rockwell Automation Integrated Architecture and Integrated Architecture Builder
- Commercial Engineering Support
- Ethernet and Digital and Analogue I/O Modules
- IAB Migration Tools
- More effective programming solution
- Simpler process optimisation
- Unitisation of the incinerators
- Greater autonomy of plant operations
- Significant throughput improvement per burner
Waste disposal and energy-generation centre switches over to ControlLogix based solution using proven and highly effective migration programme
Established in 1975 to provide quality system integration service solutions into a wide range of industrial market sectors, MCS Control Systems Ltd experienced rapid growth and has now established a firm reputation for manufacturing quality MCC and PLC solutions, including SCADA, MES and PLC software.
The company also has an experienced software team, providing expertise in the design and implementation of HMI, SCADA, CIM, MES and specific integration at the top-end of control systems and materials handling, meeting the need for information connectivity between IT and production.
This combination of expertise means that MCS Control Systems Ltd. is now fully equipped to offer full turnkey systems capabilities, incorporating CDM 2007 Principal Contractor status, for process control system solutions, whilst the individual divisions are able to offer personal, specialist solutions to meet client specific project needs.
In a recent project involving the upgrade of a joint-council operated waste disposal and energy generation centre in the UK – which produces 17.7 MW of electrical energy from 245,000 tonnes of waste – it successfully upgraded a now obsolete control infrastructure to one that leveraged the contemporary performance and flexibility of an Allen-Bradley® ControlLogix® programmable automation controller (PAC) and associated automation solutions from Rockwell Automation.
MCS was tasked with replacing an aging Allen-Bradley PLC-5®-based control architecture, which controlled two steam turbines and three furnaces, with a more up-to-date solution without changing the footprint of the installation and using the existing cabling and wiring infrastructure.
The plant’s operators were finding that maintenance and repair were becoming difficult and were no longer cost effective; indeed if both primary and secondary PLCs failed all three incinerator units would become disabled.
According to Stewart Foster, sales director at MCS Control Systems, the big question is ‘do you migrate to a newer solution or replace the entire infrastructure’? “To replace the entire control platform would have meant major long-term downtime and would require a solution that would need proving and testing prior to installation and commissioning,” he explains. “By using the existing infrastructure, it can be a lot cheaper and there are significant advantages for the end customer. All in all it is a better idea and in this case a better solution.
MCS was given a four-day window to perform the changeover, testing and configuration on the common services, this included two of the four days with no power on site as the company had to take all power off line.
The solution deployed by MCS Control Systems was centred round a migration programme which would deliver and integrate a new contemporary control architecture supervised by three independent dual redundant ControlLogix PACs.
The code in the PLCs was converted and the relevant sections for each of the three units were filtered to the three dual redundant ControlLogix systems. The original wiring harnesses were reused with the I/O conversion kit to allow fast and effective changeover without any major disruptions to the existing wiring. This also gave a short ‘emergency’ fall-back window should any problems arise with the new system.
Alongside the PACs and the Integrated Architecure Builder (IAB) migration tool, the Allen-Bradley based infrastructure also comprised Ethernet modules and various digital and analogue I/O modules, along with a field wiring conversion module. The company also used support of a commercial engineer from Rockwell Automation.
The new Logix-based system was replaced in three stages: unit 1, unit 2 and then unit 3 along with the common systems. During the first and second stages the old PLC-5 system needed to continue operating the non-migrating units, which required temporary legacy Data Highway + communications to allow the PLC-5 and Logix systems to communicate.
By using Ethernet as the communication backbone, MCS Control Systems and the end customer have the option to expand the facility even further into the Connected Enterprise. This will allow the collection of real-time performance data, historical data for performance assessments and maintenance schedules and connectivity beyond the facility into enterprise systems that can help manage the equipment even more precisely in line with other assets on site. The use of standard Ethernet within EtherNet/IP™ means that there is very little that needs to be done for these connections to be established; and full security solutions are also available for user control and to prevent unwarranted access.
According to the engineering manager at the waste centre: “The greatest impact on availability of the plant was on the common services I/O and we managed to maintain the operation of the plant within the timescales that we had set ourselves. Over a four day shutdown, two days without power.”
Foster concludes: “The plant’s operators now have much more effective programming solution with which they are comfortable; especially with regards to process optimisation. The new solution and integration allowed unitisation of the incinerators and gave greater autonomy of plant operations. They are also seeing significant throughput improvement per burner. We also used a lot of ETAPs on the Ethernet network, for breaking and jointing. The 1783-ETAP modules, gave us the ability to connect single-port devices to a ring or linear topology; we had good help from Rockwell Automation in this respect.
“My personal relationship with Rockwell Automation spans some 30 to 35 years,” he concludes, “and MCS has been a Recognised System Integrator (RcSI) since 1992. We get a lot of benefit from the technical support guys at Rockwell Automation, their technical capabilities are excellent. The pre-sales support is top class and in the core market, Rockwell Automation is very focussed.”