The millenium bug: don't let it bite you.

This nasty computer defect will likely pop up somewhere in your plant, but you can keep it from spoiling your New Year's Day 2000. The key is to hunt out all the places it can hide before time runs out. So get started now.

* Even if the worst doomsday prophecies don't come to pass, the "Year 2000 problem" poses a real threat to your shop-floor control systems. This now-infamous computer glitch - also known as the Millennium Bug or simply as Y2K - results from the inability of older computers, embedded processors, and their respective software or firmware to handle calendar dates after Dec. 31, 1999. Rather than reading a year as a four-digit number, some older manufacturing control systems refer to a year only by its last two digits. This bit of programmer's shorthand means that years 2000 and 1900 both become "00," resulting, to put it mildly, in some confusion. Come New Year's Day 2000, and in the months that follow it, manufacturing control systems dependent on two-digit date notations in their software/firmware won't work well or will crash altogether.

Despite the potential for disaster, the news doesn't appear to be all bad for plastics processors. The bulk of Year 2000 problems will affect higher-level, plantwide systems. "As your automation complexity increases, your chance of Y2K issues increases," explains Bart Polizotto, manager of plastic products for Barber-Colman Co. in Loves Park, Ill. Yet truly complex plantwide systems are not that common in processing plants. "Most plastics businesses are small enough that their Year 2000 problems will be easily manageable," predicts Dr. Nandu Thondavadi, president of Mascon, a supplier of MRP-II systems and Year 2000 consulting services in Schaumburg, Ill. "On a difficulty scale of one to 10, I'd say most plastics plants are a three."

Unfortunately, the news isn't all good either. You have just about 500 days left to check out the Year 2000 readiness of every control and monitoring device on your shop floor and of every plantwide automation and information system. Because all these systems have become so interdependent, Year 2000 audits have to be exacting and thorough. "Every manufacturing control system needs to be viewed as suspect until proven otherwise," says Kurt Schmidt, marketing director for TAVA Technologies, Inc., a large systems integrator and Year 2000 consultant in Englewood, Colo.

Even in a small plant, checking out every one of your computer-operated devices will take some time. So don't delay. Here's a look at the areas likely to cause problems and what you can do about those problems when - not if - you find them.

Machine controls

Looking at manufacturing systems in general, PLCs and proprietary machine controllers with customized embedded processors provide ample hiding places for the Y2K bug. Fortunately, much of the hardware commonly used to control plastics machinery may not be that susceptible to the bug. According to Nick Hunkar, v.p. of Cincinnati-based Hunkar Laboratories Inc., "A lot of plastics machine controls don't care what year it is." He adds that even some of the embedded processors used in proprietary machine controls don't contain date fields and thus pose no problem.

To take an example from a leading compounding machinery supplier: "Most of our lines are still based on a PLC without a real-time clock," explains Richard Taylor, engineering director at Krupp Werner & Pfleiderer Corp. in Ramsey N.J. Rather, it is only the higher-level supervisory systems that make use of dates.

However, many sophisticated machine controls, whether off-the-shelf or proprietary, do indeed keep track of dates. But here again, the problem doesn't appear to be all that drastic. Several leading injection molding machine suppliers claim that their current controllers will roll over to the year 2000 without incident. Older proprietary controllers, however, are an open question and need to be checked.

As for off-the-shelf PLCs, vendors that sell extensively to plastics machinery suppliers and processors claim that their current models are Year 2000 compliant - that is, they can handle dates from Jan. 1, 2000 onward. Barber-Colman's widely used MACO controllers, for example, will all handle the Y2K rollover, according to Polizotto: "The older MACOs didn't have real-time clocks, so they have no problem. The new MACOs have clocks that handle four-digit dates." Rockwell Automation/Allen-Bradley, Mayfield Heights, Ohio, makes similar claims for its plastics-oriented systems. Steve DeLonge, the company's manager of plastics products, says that plastics machine control systems based on current generations of Allen-Bradley PLCs and SLCs have no Y2K issues.

The hardware itself represents only one part of the problem. Remember that PLCs have a software component too. "Even if our PLCs and SLCs don't have an issue," says DeLonge, "the thing we never know is whether they run a program with a two-digit date." Likewise, Polizotto notes that much of the complexity of the Year 2000 problem comes from the fact that PLCs are a general tool and are often customized by the OEM or end-user.

What's more, even Y2K-compliant PLCs may be vulnerable to trickle-down effects from seemingly innocuous, non-compliant devices. Polizotto has seen a few installations where the PLC has been synchronized with plantwide automation systems for purposes of materials handling, start-up/shut-down, or issuing alarms. If the date information from the plantwide system is incorrect, it might send erroneous information to the PLC. "Shut-down in these cases is theoretically possible but unlikely," Polizotto says. This sort of condition would be more of a nuisance than a disaster, he predicts.

Plantwide automation systems

Moving up a level in the automation hierarchy, plantwide systems that handle process and production monitoring, supervisory control, and manufacturing resource planning (MRP-II) provide the most fertile breeding ground for the Millennium Bug. "These systems attribute just about everything to dates and times," says Jonathan Zook, product manager at Syscon-PlantStar in South Bend, Ind.

Major vendors of plastics-oriented systems for process/production monitoring and MRP-II report that the current versions of their software are fully Y2K compliant. The problem is that some users still run older systems whose software can't handle the date rollover. "Anybody using a DOS-based system has the problem," says Hunkar. The same goes for some older systems based on mainframes or minicomputers. And that warning goes double for older custom plantwide applications software, whose homegrown computer code is a "major problem," says Polizotto.

For the commercial systems, the older non-compliant versions are an ever-shrinking minority as users upgrade to current, Y2K-compliant software. PlantStar's Zook, for example, believes that only a handful of customers still face a software problem - those running the firm's oldest Focus 100 system, which runs on the OS/9 operating system. PlantStar has developed a free software fix for Focus 100, but Zook expects that most users will instead choose to upgrade to more modern client-server systems.

Likewise, Data Technical Research of Jacksonville, Fla., has only eight customers left using the non-compliant DOS version of its MRP-II system for plastics processors. "All of them had planned to upgrade by the millennium anyway," says DTR v.p. Rusty Russ.

Outdated supervisory control and data-acquisition (SCADA) systems can also cause problems. "Some SCADA systems still have an embedded chip with a two-digit date," explains Mascon's Thondavadi. Barber-Colman attributes at least part of a recent upswing in sales of its new Foxtraker SCADA system to the replacement of noncompliant SCADA systems.

Perhaps an even more pervasive problem with the plantwide systems can be traced to the personal computers that are used as clients - and even as hosts - in client-server systems. "The core problem is in older PCs," explains Zook, because their BIOS (basic input/output system) can't handle the year 2000 rollover without displaying an incorrect date or crashing altogether.

Process sensors and auxiliaries

In contrast to the higher levels of automation, the measurement devices at the bottom of the automation food chain should be relatively immune to Y2K problems. Bill MacAllister, marketing director at Branden Technologies in Wilson, Ore., points out that process-monitoring systems for plastics still interface directly with plain-vanilla analog sensors and some digital transducers, neither of which have a clock function. "We don't usually tie into a lot of high-level devices that use dates," he says.

Another Y2K bright spot can be found in plastics auxiliary equipment, much of which has no clock function. Even the most sophisticated plastics auxiliaries for tasks such as materials handling tend to leave scheduling and other date-dependent work to plantwide networks. The Conair Group, Pittsburgh, which makes just about every type of auxiliary equipment, reports that it has tested all its equipment that has internal clocks and has not found any difficulties.

Still, you should not rule out auxiliaries as a source of Y2K problems, especially when you consider the potential trickle down effect of computer glitches in non-critical systems. Both Polizotto and Thondavadi, for example, point out that simple time and date stampers often have embedded chips that support only two-digit dates. While some customers can tolerate an incorrect date stamp, others - such as in the medical industry - may reject otherwise good products bearing the wrong date.

What to do about it

Once you've performed a detailed inventory of all the date-dependent systems in your plant, don't be too surprised if you find at least a few problems. "We've looked at hundreds of plants," says TAVA's Schmidt. "And we have yet to find one without any Y2K problems."

So what do you do about them? For problems that reside only in your software, you may be able to fix the code - such as with the software "patch" available to users of PlantStar's Focus 100.

In most cases, however, the problem will also have a hardware component, and it will make more economic sense to simply replace or upgrade the vulnerable systems. Most of the DOS-based systems that won't roll over to the Year 2000 are due for retirement or an upgrade anyway, say vendors. Some vendors, such as Branden Technologies, are even offering discount prices on upgrades to users whose older systems will fall prey to the Millennium Bug. Hunkar Laboratories will perform a Y2K audit for its customers for a fee that includes the price of any upgrades or other remediation found to be needed.

While it is possible to test for potential Year 2000 problems yourself - by setting the clock forward on the PLC or machine controller - your best bet with complex systems may be to seek some help. As a first step, ask for Y2K compliance statements from all your control, automation, and machinery vendors. Some controls suppliers have posted compliance statements and information on their World Wide Web sites. Allen-Bradley, for example, offers a product-by-product listing of Y2K compliance at www.ab.com. Barber-Colman does the same with its compliance information at www.barbercolman.com.

For those willing to pay a fee for professional help, Allen-Bradley's DeLonge also recommends certified systems integrators as good sources for Y2K consulting. Integrators, unlike some firms offering generic Year 2000 consulting, bring a hands-on, shop-floor perspective to the problem. "It is wise to bring in someone with manufacturing experience," DeLonge advises.

Hazards of interdependency

Even if you have taken stock of your shop-floor systems in minute detail and fixed any problems you found, does that make you immune to the bug? Not when the greatest threat to smooth post-millennium operations may lurk not on your shop floor at all, but in your central-office business systems, customized EDI systems, CAD systems, and corporate networking software. The problem can come from outside your plant altogether-from your customers or your suppliers - even those of power and water services.

Your shop may be inoculated, but you may be handcuffed to a firm that got the bug. That's why Detroit's auto makers, for example, are pushing their vendors to address Y2K issues promptly. It makes good sense to inquire what your vendors and customers are doing to get themselves in shape for the millennium.

Y2K Detective Kit

It's not easy to go out and buy a quick fix for Year 2000 problems. But here's one product that may help:

TAVA Technologies, Inc., Englewood, Colo., is a large systems integrator that provides Y2K consulting services and also markets a software tool that can help pinpoint and then fix Y2K problems throughout your shop. Called "Plant Y2KOne," it allows users to link up with an on-line database of products that are Y2K-compliant, and it also provides a search feature which looks through any custom computer code on PLCs and other control devices to identify two-digit date fields.