Expertise
March has been trusted by key UK industries for decades. We understand the challenges that business faces in terms of productivity, competition, cost control, safety, security and compliance.
March was engaged by a national utilities company client to undertake a control change over at their Sewage Pumping Station; the aim was to simplify the legacy control system.
History
The Pumping Station Peak was commissioned to work on was built in the late 90’s to cater for the new trunk foul sewers constructed to facilitate the redevelopment of the Royal Docks.
The Pumping Station was controlled by a pair of Duty/ Standby GE Fanuc PLCs. Both PLCs kept identical sets of data and had more than 670 Digital Inputs/Outputs and 56 Analogue Inputs/Outputs.
The old ‘legacy PLC’ was causing operational issues due to its increased unreliability and non-maintainability. There was also no longer a requirement for a Duty/Standby PLC configuration.
Solution
March managed the replacement of the legacy PLC and all 10 I/O Racks with new ControlLogix hardware.
A new HMI was also installed to allow for better visibility and control of the site for the Operators. As part of the design, March provided a detailed site survey on the ICA panels which formed the new detailed electrical design. The existing software was reverse-engineered for the new PLC control philosophy and the design was further developed with the client to make it future proof and provide the control and efficiency required • A new fibre optic ring network was designed to link the remote I/O racks in the various locations to provide a robust and resilient solution • The changeover method was to run the Sewage Pumping Station in hardwired backup control (i.e. solely on level controllers with critical alarms being monitored by regional telemetry). This way Peak could remove all the PLC equipment and internal cabling between the PLC and field terminals, without any risk to the process.
Results
March successfully completed the control change over with numerous positive results. The installation of new equipment and tidying of the panel wiring led to significantly reduced process risk. The client team are now easily able to maintain and modify The PLC and HMI when necessary. Revised control of equipment has reduced the stress on-site assets ensuring a robust, reliable and efficient solution and the new HMI allows for better visibility of site operations and statuses, including power consumption and level trending, helping to pinpoint any future issues and increase site efficiency. The newly installed tidy panel wiring to field terminals and updated detailed electrical drawings during the installation of the new hardware has simplified wire tracing and fault finding and will reduce equipment downtime.