MANUFACTURING SYSTEMS: SPECIAL REPORT
Year 2000 Supplement-September 1997
Story 1: Something short of disaster
Story 2: Century Crisis
Story 3: In with new...
Story 4: The means fit the ends
Story 5: WHEN 2000 HITS THE FLOOR
Story 6: The quicker the better...
STORY 5
When 2000 hits the floor
Plant-specific automation, systems pose special millennium
challenge
Roberto Michel
Associate Editor
The turn of the century is a call to arms for information services (IS)
professionals and manufacturing managers alike. As 2000
approaches, project teams huddle in corporate meeting rooms to
discuss strategy, and test beds hum with activity. However, say some
observers, in the race to find and fix problems in classic
corporatewide systems like financials, plant-specific systems may be
overlooked.
"The scope of Year 2000 projects, which tend to be IS-led, often
ends at the plant level, except for applications with a financial tie-in, or
networking and communications," says Ken Owen, a principal
consultant for Fluor Daniel, a systems integration, software, and
engineering services company.
As part of its integration work, Greenville, S.C.-based Fluor Daniel is
developing a Year 2000 practice focused on plant-specific
applications and industrial automation systems. "What we've found is
that for hundreds of plants, millennium compliance is an unattended
situation," says Owen. "In some cases, Year 2000 projects may not
even touch plants, even though they have sophisticated systems."
Operational systems in plants function at planning, execution, and
control levels. Millennium compliance problems may exist in any
application at these levels that uses 2-digit data structures for years.
When the century turns, these 2-digit structures may treat "00" as
1900 rather than 2000, leading to incorrect calculations, or possible
system shutdowns or malfunctions. To complicate matters, the
problem exists not only in applications, but in certain hardware,
firmware, and operating systems.
Industrial automation systems feature just such a mix of hardware,
firmware, and software. PLCs, or programmable logic controllers, are
chief among the embedded systems used in manufacturing, though
smart instruments and robots also use microcontrollers. PLCs are
stored program devices that control large numbers of discrete
elements, using very fast I/O scan times. Early PLCs rarely performed
arithmetic functions, though some of today's PLCs do.
Controllers also work in concert with other computers and
applications that provide man-machine interfaces to the control level,
or serve as data historians for plant-floor processes. Date-aware
historian applications, as well as intelligent instruments that use
real-time clocks, are among the plant-specific control systems that
pose millennium risks.
Those charged with the viability of plant-specific systems need to
inventory all their automation systems, say experts like Owen, and
focus on those that pose the greatest risks. A few bad time stamps
may not threaten operations, but corrupt quality control data, or
missed machine alarms,ÿcan wreak havoc quickly.ÿAnd while
industrial automation systems may beÿlessÿdate orientedÿthan
corporatewide applications, they poseÿÿspecial challenges in
assessingÿÿYear 2000 exposures.
Customized heritage
Bob Brown is a software engineer who has, during the course of his
career, designed manufacturing control systems for several large
manufacturing firms. Today, Brown is vice president of Bluegrass
Year 2000, a volunteer group of IS and industrial engineering
professionals in the Lexington, Ky.-area who are studying Year 2000
problems. According to Brown, diagnosing millennium problems at
the control level is difficult because many of these systems are a mix
of sensory devices, computers, controllers, and customized firmware
and software.
"Most business managers cannot fathom how complex some of their
internally developed, homebrewed manufacturing and process control
systems have become," says Brown. "Some systems have evolved
over a course of years with contributions from numerous engineers,
programmers, and technicians trying to squeeze a few more
production cycles from antiquated equipment."
Most PLCs will not be affected, says Brown, since they work on the
concept of elapsed time rather than dates. What has to be looked at
to determine whether a PLC or automation system will be affected is
how the entire system functions. "Some PLCs are involved in date
coding," he says. "They may work in conjunction with a computer or
a PC on a network to do things like print date codes on products."
Dan Miklovic, a senior analyst for Gartner Group, a market
research firm based in Stamford, Conn., agrees that Year 2000 risks
involving industrial automation require a systemic perspective. "With
embedded systems, the problems most likely to be encountered are
with smart instruments, or sophisticated gauging systems that use
real-time clock chips to calculate date-dependent recalibration
intervals or other maintenance routines. Most PLCs, up until recently,
didn't use real-time clocks."
But even though this basic control level is unlikely to have problems,
says Miklovic, other upstream points in systems may be prone to
them. For instance, he says, most PCs installed prior to mid-1996
have basic input/output systems (BIOS) that can cause Year 2000
problems in the way they compensate for a 2-digit real-time clock.
These BIOS append "19" to the front of the 2-digit information during
reboot operations. If a reboot occurs after the turn of the century,
affected PCs will be told it's 1900, and since these PCs usually run
DOS or Windows operating systems, they will default to 1980 or
1984, causing applications to malfunction.
"The fixes for these BIOS are fairly simple, but there are many PCs
on plant floors with bad BIOS that are used to run data acquisition
applications," says Miklovic. "These systems probably will clip along
fine right through 2000, and will fail only when a reboot occurs due to
major maintenance or an extended power outage."
Prior to PCs, a generation of computers, such as Digital VAXs and
PDP 11s, were used in conjunction with PLCs, and may still be in
use, Miklovic says. These older computers (dependent on how new
an operating system they use) are vulnerable to Year 2000 problems.
Unlike PCs used in front-office systems, where exponentially faster
microprocessors and memory-hungry software upgrades drive rapid
hardware turnover, computers at the control level are built to do a
specific task that may not change for decades. "The catch is these
systems are rugged, and most companies don't change them as long
as they are working," he says.
Data acquisition and data historian applications are prone to Year
2000 problems because they tend to be date-aware, says Fluor
Daniel's Owen. Also, heavily automated systems often rely on LANs
for dates and times, which means network compliance considerations
also may come into play.
"The bottom line is that it's dangerous to make assumptions about
PLCs and embedded systems. You have to ask how controllers are
being used and how they function in larger systems," he says. "With
each component, you must contact the vendor, because these systems
are made from components in the same way a PC consists of cards
and circuit boards from a variety of vendors."
Vendor activity
Vendors of PLCs, process control systems, and industrial automation
products typically are engaged in reviewing their product lines for
Year 2000 compliance.
Rockwell Automation, Milwaukee, is reviewing all of its industrial
automation products for Year 2000 compliance, says Joe Owen,
director of commercialized engineering. In the case of Rockwell's
PLCs, a few older models use 2-digit date structures, but most are
free of problems.
Even with compliant products, he says, a programmer may have
masked two digits out of the date structure in an effort to conserve
memory. "In working with customers, we are focusing on those
instances where a compliant product has been modified. It can be
time consuming because you have to check the programming," he
says. "It would be relatively simple if it was just a matter of the vendor
checking all products to see that the century rolls over, and leap years
are handled properly."
At Fisher-Rosemount Systems, a process-control system vendor
based in Austin, Texas, minor Year 2000 issues exist with some
products, but these are being addressed by version upgrades and
plant-specific service programs, says Dave Imming, manager of
integration solutions. The company first identified which products had
a concern, and then folded a fix into upcoming product revisions, or
scheduled a fix if the product wasn't up for revisions. For customer
installations, Fisher-Rosemount likewise is folding any Year 2000
analysis into ongoing work. "We try to match any Year 2000
revisions with the customer's system life plans," he says. "It's more
practical, because you don't have to go out and create completely
new staffing and training patterns to address the problem."
Unlike production planning and scheduling applications, where
planning and procurement horizons already are pushing the century
mark, Year 2000 problems in process control may not manifest
themselves until the new millennium, says Peter Martin, a vice
president with The Foxboro Co., a Foxboro, Mass.-based process
control system vendor. "The systems we build essentially are real
time," says Martin. "But that doesn't mean you should wait until 1999
to do anything about them."
Foxboro is assessing potential Year 2000 problems with its systems
and applications, says Martin, and adds that any fixes necessary will
be in place well before problems occur. Newer client/server systems
for "soft control" of process automation also are being assessed.
"Client/server has nothing to do with whether a system will have
problems," says Martin. "It's true that our newer client/server systems
look clean, but any application that uses dates has to be suspect."
One factor that bodes well for man-machine interfaces and other
client/server process control applications is that the operating systems
involved typically are compliant, says Martin. It's also much easier to
set up an off-line testing environment for open client/server systems
than with automation systems that rely on proprietary hardware or
embedded logic, he says.
How to proceed
An inquiring mind may be the best defense for managers assessing
Year 2000 problems at the plant level, says George Girod, principal
consultantÿfor Keane Inc., a Boston-based system integration firm.
Manufacturers can turn to integrators or vendors for help, he says, but
tools to automate Year 2000 analysis are h
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