By Nels Tyring, Chairman, TVC Systems
IT ALL started in the early 1970s with the debut of the programmable logic controller (PLC), which allowed discrete manufacturing and smaller process plants to enjoy the benefits of automatic control. Before this time, the automatic control market was the province of large process plants and manufacturers of direct-digital and then distributed-control systems. The PLC and the advent of the microprocessor a few years later changed the game. Since applications for PLCs tended to be below the horizon of the large controls manufacturers, and since a good deal of specialized knowledge was required to apply them, a new kind of third-party implementation was required, and a new industry sprang up. These firms came to be called control system integrators (CSIs).
These CSIs multiplied rapidly, and by the late 1980s, there were more than 2,500 in the U.S. alone. Since there was no accepted definition of what a CSI should look like, what they should do, what methodology they should use, or how they should run their businesses, it was an easy-to-enter and easier-to-go-broke-in business. Firms came and went in rapid succession, leaving a lot of their customers with less-than-satisfactory systems, little or no documentation, and sometimes a total lack of support.
Defining the Job
In 1994, a group of well-established and successful CSIs formed the Control and Information System Integrators Association
(CSIA), and first set out to define CSIs and their essential parts. This resulted in the Best Practices and Benchmarks Manual
in 1997, and gave CSIs yardsticks to successfully implement systems and operate their businesses. The manual covered not only technical areas of producing successful, finished projects, but also the business operating practices that assure success and continuance. Potential users of CSI services now had an objective way to evaluate integrators’ technical and business practices, which could help their projects succeed. They also could gauge a CSI’s potential for providing long-term support for their project.
Three years later, CSIA established its CSI Certification Program, which are based on its best practices and benchmarks, and warranted by a third-party auditor. There are now more than 80 CSIA-Certified Control and Information Systems Integrators worldwide, and this number is growing by more than 25% per year.
Enter the Integrator
Having defined the control and information systems integrator and established standards enabling certification, we’re now facing the fact that CSIs are frequently placed where they can do the least good in the construction process. Conventionally, the CSI is considered a part of the building trades, though, in reality, there is a lot of difference in their skills, roles, and place in a project.
Just as the process engineer must define his process at the beginning of the design sequence, controls engineers must define the strategy, sequence of control communications between major equipment modules, and the overall orchestration of the automatic control of the process. They must also interface process controls to the operators, engineers, managers, accountants, and various government agencies seeking to regulate the industry.
The conventional engineering process traditionally defines the project’s materials, methods and tasks in great detail, and issues plans and specifications for construction. These detailed documents are then bid for best value by the various trades. Government-certified journeymen and master tradesmen then execute the actual construction using these documents. Engineering plays a small part in the roles of the building trades because that’s the responsibility of the engineer of record.
Sometimes Too Little, Too Late
The role of the control and information system integrator is substantially different. The bid package for controls normally contains a specification outlining customer-preferred components and their manufacturers, a process and instrumentation diagram (P&ID), a set of process operating parameters, usually in the form of ISA Instrument Data Sheets showing pressures, temperatures and allowable or desired increases or reductions in systems operating parameters, and a control points list. From these beginnings, the control engineer engineers, designs, and builds a system that will automatically perform precise, accurate, automatic process control.
The construction documents are given to the low controls bidder when the contract is awarded. This is long after many critical decisions, from the controls engineer’s standpoint, have been made about major and sometimes minor pieces of process equipment. These components increasingly have their own onboard intelligence, which also must interface with the overall plant-control system. To make matters worse, the owner frequently seeks to save money by buying the control system’s field elements before the control engineer arrives on the scene. Details of these field devices often aren’t disclosed until they’re installed, and the attempt to interface them with the control system is underway, and their appropriateness for use or connectabilty is in question.
In today’s world of increasingly smart devices, connectivity and matching protocols are critically important to the smooth, economical, and rapid startup of the plant. If the controls integration task is not properly done from the very beginning, a plant that’s 95% complete can languish in startup for weeks or months until proper function of control devices is achieved, and proper communication between critical equipment is allowed to effectively interface with the overall plant supervisory control and data acquisition system (SCADA).
Bring Integrator in Early
Since control and information system engineering is an engineering task at its heart, it should be handled in much the same way as the site civil, structural, building, process, mechanical and electrical engineering tasks are handled. The CSI should be a part of the design team, and must be brought into the design phase prior to the selection of major equipment and control components to review them from a control system standpoint. The CSI should be selected based on similar criteria and with same care as the responsible engineering firms. These criteria include credentials, length of time in business, appropriate experience, competence, references, and knowledge of the process and the industry.
Leaving the CSI’s is critical engineering tasks out of the design process, automatically selecting the low bid, and putting the CSI under the supervision of the construction manager or general contractor is an invitation to an unsatisfactory controls system. It also can mean a long and expensive startup, a potential controls disaster, and the added expense of the construction manager’s markup on controls work in which he plays little or no part. Many users have learned the hard way where the CSI truly belongs on the construction team, and now carefully select and position the integrator where he can bring the most value to the design and construction process. The CSI should first be a member of the design team, and then transition into the construction process as the owner’s controls engineer, working with the design engineer and the installing trades. This will help to assure smooth startup of a plant that is truly under the automated control of a precisely designed, fully developed, and carefully installed control system.
Questions For Integrators
From a Plant Engineer
Provide a list of references and/or trade and professional certifications or affiliations that indicate comitment to industry best practices and guidelines.
Regarding your experience in chemical processes or manufacturing, do you have experience implementing Advanced Controls?
Are you familiar with ISA-88 or implemented batch controls? If so, describe your experience.
Is your company a registered member of the Control Systems Integrators Association (CSIA)?
Describe your experience in the integration of and networking of open systems using OPC, Control Net, Foundation Fieldbus, Modbus and others.
Now, more than ever, manufacturers rely on good systems integrators to "peak lop" in times of high capital expenditure. But more than that, many of today's integrators offer system upgrades, maintenance and management services, and even training. They're able to do this on-site or remotely. They form relationships with a small number of manufacturers and become an extension of the workforce.
Maurice Wilkins, Chairman, WBF
Nels Tyring is commonly considered the father of control system integration, and is a successful integrator and founding member of CSIA. He can be reached at email@example.com