Having successfully completed a sortation upgrade for the client several years earlier, IDC was chosen to upgrade two further sorters on the same site. Both sorters were over twenty years old and whilst the mechanics were still in working order, the control systems had become obsolete with few spares available.
The sorters were also limited in operational features for changes to sortation plans, routing and management reporting facilities. Furthermore, the client had plans for major changes within the business and wanted a modern control & IT platform which could be integrated with other systems and was expandable and adaptable to cater for the future operational needs.
The sorters to be upgraded serviced the Warehouse Despatch operations and included a tilt tray sorter with 287 chute destinations with four automatic induction stations which were fed cartons and bags via belt conveyors from the packing areas. Two additional semi-automatic induction stations were provided for manual induction. The main drive of the sorter featured a fluid coupling drive, which provided gradual acceleration on start-up but no linear speed control for maintenance purposes. A second slat sorter provided 20 offload destinations delivering directly to bay doors. The slat sorter infeed comprised of a two-way merge which was fed from two manual packing areas. The complete despatch system included over 100 additional conveyor drives for the infeed, recirculation and waste transfer to a compactor which also required a control upgrade.
The legacy control systems for both sorters consisted of bespoke electronics hardware for the actuation of electro-pneumatic diverts and Siemens S5 PLCs connected to remote I/O over serial communications links for the control of motor drives and chute status information. The PLCs connected via bus serial communications to IBM Computers which provided a basic visual display and alarms list for the control room operators.
Before any work started, a complete review of the electrical control cabinet equipment, variable frequency drives and PLCs was undertaken. A safety risk assessment and report was also included to ensure the upgrade proposed complied with current European Harmonised Standards and the appropriate control system safety performance levels were achieved with the upgrade. As a result of the review and consideration of the future business plans a comprehensive User Requirements Specification (URS) was developed and agreed with the client.
The upgrade to the sortation controls included replacement of the obsolete S5 PLCs with Siemens S7-1516F and S7 400 PLCs. To meet the increased safety recommendations additional Emergency Stop buttons and pull cords were installed throughout the despatch area and connected into Profibus ET200 remote I/O Units. Additional safety contactors were fitted in the control cabinets and all obsolete components including Frequency Drives replaced. An additional field mounted Frequency Drive was installed to replace the Direct-On-Line contactor arrangement for the Tilt Tray Sorter main drive to improve speed control.
The IDC SimpliTrak™ Warehouse Control System (WCS), installed during the first sorter installation, was upgraded to Dual DELL PowerEdge R330 Processor with 32Gb RAM, Dual Power Supplies and 4 Hot Swap hard Drives providing a highly scalable and secure enterprise server platform. Any degradation of hardware performance is detected and email alerts automatically activated. The Dual Processors are configured in main, warm standby arrangement such that changeover from the online Server to the standby can be completed within a few minutes with no loss of data.
A SQL database with IDC’s SimpliTrak™ WCS software is installed on the servers providing SCADA and customised WebClient. The extensive SCADA package provides multiple levels of access for Remote Viewing, Control Room Operators and Engineer Mode for maintenance purposes. The WebClient allows users to configure sort plans for the sortation systems, change the active sort plan, re-target error lanes, and program direct induct-to-chute relationships. The Web Client also provides operational management staff with the ability to view performance statistics, generate reports and run queries for individual parcels.
Peter Hadley, Business Development Manager commented on the project:
“When planning the upgrade, a vital consideration for the client was the downtime needed to replace the obsolete PLCs. IDC’s experience in sortation system upgrades and the use of standard software modules meant the changeover was completed as planned with no loss of production.”
The client now has a WCS which will enable future upgrades and new equipment to be integrated as the business grows.