Partial Loss of PLC Program

Event Year: 2005 Reliability: Likely But Unconfirmed
Country: United Kingdom
Industry Type: Food & Beverage
Description:

There had been reports of problems with a control loop on the system for a number of weeks. Upon investigation, it was discovered that it was possible to delete a sequence without any notification when working on line. It was assumed that this was what had happened and it was also discovered that it was not the only sequence deleted.

Impact:

Unable to correctly control the specification of a final product.

Action Description: The Control team were all informed of the possibility of this happening and the supplier was informed that a modification should be made to their software.