Change management software cuts production downtime

The Wakefield manufacturing plant of Coca Cola Enterprises (CCE) was built in 1989 as a manufacturing and distribution centre for CCE in the North of England. The plant is the largest soft drinks factory in Europe, covering an area of 41 acres and has 72000 square metres under of buildings. The warehouse has grown from a bulk storage facility housing only Wakefield-produced drinks, to a regional service centre for handling product from regions across the UK.

High-tech machinery at Wakefield enables cans to be produced faster than the eye can see. The plant is capable of producing up to 4000 cans per minute and 3280 bottles of soft drinks per minute across nine lines (two canning and seven PET). The factory also boasts the fastest two-litre bottle production line in the world.

In 2004, UK-based control and automation specialist M A C Solutions (UK) Ltd was initially asked by CCE Wakefield to recommend how the plant could improve its existing change management and version control process for industrial programmable control devices.

At that time, policing changes to PLC code at the plant was proving to be problematic. The original procedure included using two separate back-up systems: a 'master' and a 'working' system based on floppy disks. Technicians would change PLC code locally and then follow a set of procedures to ensure the change was recorded and backed-up.

In production plants, changes to PLC code are necessary for a variety of operational reasons. New control and automation equipment may be purchased that requires changes to the software code within the PLC. A new inverter drive, for example, may need to be fitted to a production line, in order to improve productivity or operational efficiency.

A new electronic pressure control device may need to replace the existing mechanical version or the timing of a bottling conveyor line may need minor adjustments. These would all require this type of PLC code change.

If a change was unauthorised or the engineer was simply so busy that he forgot to save the change to the main back-up file, version control issues would arise. If just one production line goes down because a PLC has fallen over due to poor software version control, the plant is faced with downtime costs of around £1,000 per minute. Therefore, a reliable, easy-to-use change management software suite was critical.

The CCE Wakefield plant uses a range of programmable control devices, including 93 Siemens S5 PLCs, 11 Siemens S7 PLCs, 20 Allen Bradley (Rockwell Automation) ControlLogix PLCs, 31 Allen Bradley SLC500 PLCs, and 26 universal Devices (SCADA InTouch and others).

These PLCs are located on several networks across the site, including a legacy Siemens S5 H1 network, with some PLCs and devices being standalone without any connection to a network.

Mass AutoSave (from US-based software supplier MDT Software) is an enterprise source management solution that provides a full suite of tools to protect, save, restore, discover and track changes for industrial programmable devices and documents. The system unifies plant automation software under one common user interface, resulting in a secure, well documented, controlled environment that significantly reduces the time and effort needed to manage a manual backup system.

Mass AutoSave's 'Scheduled Compare' facility enables administrators to automatically schedule compare procedures.

Automatically comparing the program in the device with a program stored in the AutoSave library can detect and identify changes between the program that may have been unknown or unauthorised. This therefore protects that company's process, people and equipment.

When a change is made to a PLC program, the software can be set up so that designated users are immediately notified via email.

Detailed, logic-to-logic and selected data table value comparison reports are generated and users are notified of differences via email. These mailed results, generated for schedule, program, or demand compares, are viewed via a web browser that features hypertext links to detailed logic and documentation differences.

The system now polices itself on the networked PLCs using the software's 'Scheduled Compare' facility within MDT Software's 'Mass AutoSave' software suite. Reports detailing discrepancies between archived PLC code and actual PLC programs are produced, which can be viewed and checked by an administrator and discrepancies emailed to the appropriate individual at CCE.

- For more information, visit www.mac-solutions.co.uk

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