A banner day is approaching for the group of dedicated volunteers who have been quietly and methodically going through the steps necessary to take the OMAC Packaging Workgroup (OPW) guidelines beyond their “guidelines” status and turn them into a genuine ISA standard promulgated by the Instrumentation, Systems and Automation Society.

There’s no better place to begin such an update than with PackML, the “packaging machinery language” built on a universally accepted state model. Recently published was PackML Version 3.0, an upgrade on Version 2.2. According to Mike Lamping, a technology leader at Procter & Gamble, as well as the committee chair for PackML, Version 3.0 is significant for the number of machine states that have been added and the introduction of the concept of a Machine Control Mode.

More modes

A primary driver behind the work that led to Version 3.0 was the recognition that so many packaging machinery operating conditions require more modes than “automatic.”

“What we added was the concept that now an infinite number of machine control modes is allowed,” says Lamping. “You can have an infinite number of machine control modes and PackML actually says, ‘Okay, you can do multiple machine control modes, but the state diagram always uses a subset of the defined 17 states. You can only have 17 states. You don’t have to use every one of those states, but you’re never going to have more than 17 states.’

“The 17 states were based on the ISA-88 Part 1 concept of using a state diagram to represent a component of equipment operation, which is exactly what PackMLVersion 2.2 was based on. So what we did for Version 3.0, as far as states go, is add the states that weren’t accounted for in Version 2.2. So now you have what might be called an ‘ing’ state before every quiescent state. Each ‘ing’ state has a procedural operation that can direct the machine automation to successfully carry out what is necessary to achieve that ‘ing’ state. For example, instead of just ‘suspend,’
we now add ‘suspending.’ Similarly, we add ‘completing’ to ‘complete.’

“Or let’s say you’re in the ‘run’ state and you want to go to a ‘hold state.’ With Version 3.0, you go from ‘run’ to ‘holding’ to ‘hold’ to ‘unholding’ and back to ‘run.’ ”

Each Machine Control Mode will very likely have a different procedural operation to carry out the intent of an “ing” state to meet that Mode’s requirements. Starting in a “Production Control Mode” situation could be quite different than starting in a “Maintenance Control Mode” situation.

PackAdvantage committee

Meanwhile, Siemens Vertical Marketing Manager Bill Henderson, the leader of OPW’s PackAdvantage Team, is busy formulating plans that focus on what might be called the OPW “message.”

“At a recent executive council meeting, we all agreed that OMAC, which of course stands for Open Modular Architecture Controls, doesn’t exactly roll off the tongue,” says
Henderson. “We need to create a keen message and put our marketing efforts behind that message.”

Henderson believes that a strong marketing plan is one of the key components that OPW has gone without. There’s been considerable energy spent on communicating the benefits of adopting servo control in packaging machines, but he thinks more can be done if the OPW guidelines that are now becoming an ISA standard are viewed as a product ...