The value of state models

Conducted by our resident packaging automation blogger Keith Campbell (www.ontheedgeblog.com), it's an interview of Ken Ryan, director of the Center of Automation and Control at Alexandria Technical College, and Shane Loughlin, an automation consultant and integrator at Ireland's SL Controls. Here are some highlights:

• Loughlin: "To increase overall equipment effectiveness [OEE], data on machine states is crucial. We're finding that by using the S-88 state models, we can do state model analysis to try and minimize high-frequency/short-duration stoppages. We also use ISA S-99, the cyber security standard for the manufacturing environment, to try and provide an escalation path back to the OEMs and have that integrated into the procurement process so that we can try and escalate issues very, very quickly to the packaging machinery OEMs and the technology providers. The S-99 cyber security framework gives a very strong framework for communication with the IT department, which typically finds it difficult to get to grips with a manufacturing environment."
• Ryan: "It's so important to have good sound data analysis if you want to pinpoint just what are the high-frequency/short-duration stoppages on packaging machinery, stoppages that are impairing overall equipment efficiency. We're finding that such analysis can only be done by leveraging the type of power that comes out of the IEC 61131 language—like structured text—and having a sequential function chart to show you the machine states."
• Ryan: "We've come to the point of tearing down what our preconceptions are in education about how we train automation. It had to come right back to how do we think about the automated process overall. Because if we don't think of them as state-based processes, then we really can't get to designing programs and automation systems that allow us to get at the data that tells us what state a machine is in, how long it's been in that state, what kinds of alarms and warnings do we have in those states. That information is crucial because it can be leveraged in an analytical environment to improve a machine's efficiency."