Severn Tunnel Pumping Station
Control System Upgrade
Amco Giffen (Formerly Amalgamated Construction) are a leading contractor for complex and innovative multidisciplinary engineering projects. When it came to the upgrade of the pumping station for the Severn tunnel, Amco required a company that had experience executing control system upgrades in a timely and professional manner. As a company that has worked on various projects of this nature, Adbro Controls Ltd were the perfect fit. They approached us to work alongside them on the upgrade thanks to our experience and knowledge of complex control systems, and familiarity of this type of work.
After on-site surveys were completed it was discovered that the PLC hardware within the current system could no longer be supported. There are various reasons why this happens. Older systems can include parts that are now obsolete, therefore replacement parts are no longer obtainable. Programming software can become out of date. Software that previously ran on one platform, may not be supported by another. This can cause issues in the future when it comes to maintaining the system and keeping everything running smoothly. With various factors in mind, it was decided that a new and improved, modern solution was required to ensure a single point of failure would not stop any of the systems on site.
The main focus for this project was to upgrade the PLC’s in the current system, as the existing components included those that were now obsolete. To rectify this issue, the new design included parts that were a lot easier to obtain. This helps avoid any delays when it comes to future maintenance work on the system, thus reducing the risk of a repeat situation where Amco are left with an obsolete system gain. Part of the upgrade included standard Siemens S7 1500 PLC’s and Westermo network switches.
In total 13 PLC’s were implemented into the new system. Of the 13, 6 pairs were set up. These were installed as a master/ standby configuration to give redundancy in the event of a PLC failure. The network switches in the system were configured to give a total of 4 RSTP Rings. Thus providing Amco with an automatic backup system that would continue to keep the station running, should an issue occur. This is was an important feature to implement due to the extreme impact these issues would cause to the site, without a support system put in place the results could be catastrophic.
With it being a large site location and operators working in various areas throughout, it was important that the upgraded system could be accessed easily regardless as to where the operators were working within the facility. The most appropriate way to enable this, was to install 7 Wonderware InTouch workstations in various points throughout the site.
Overall the Pumping station control system upgrade was a success. The new design provided Amco Griffen with a more efficient and reliable system. As a result, the new system considerably improved the day to day running of the pumping station site.
Those working on site can now rely on the new extensive set of alarms implemented in the upgraded system to alert them should any issues occur. Enabling them to act quickly to rectify any problems if they occur. As a result, the response time to any issues will improve.
The back up system put in place by Adbro Controls allows the pumping station site operations to continue as normal, without disruption should anything occur. By implementing the system, operators are able to attend any issues reported without causing an impact to the usual running of the site.