The Benefit of Outlines and Flow Charts for Industrial Project Development

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. Tnis is Tip #16.

As a student in high school, I struggled when writing papers. I had a lot to say, but the resulting jumble of thoughts and ideas was poorly presented and confusing to the reader. A ninth grade teacher hammered me for this, and ultimately taught me that no article or paper could be successful if it lacked a logical organization. He preached the concept of first creating an outline to assemble the main concepts in a meaningful and logical way, and THEN fleshing out the paragraphs. This is a lesson I never forgot, and as I got into automation, I realized this same approach is just as critical to any kind of software developmentflowchart diagram.

Concept: This applies to any major undertaking (such as writing a paper, making a presentation, or designing complicated batch code). Take the time to lay out a design and get the underlying structure right before you begin. You will save yourself hours of wasted effort, and your work product will be much more cohesive.

Details: When faced with a major creative endeavor, most people want to jump in and get started so they can feel that they are making progress. They sit down and immediately start writing/painting/banging out lines of software code. This method can eventually work, but the path to success will be a circuitous one full of wrong turns and rework.

Save the team a lot of wasted effort, and take the time to work out a solid framework before starting on the details. This concept applies to any major project but is especially true for software development. If you first outline the major components and think through how the parts will interact, the resulting code will be much simpler and testing and start-up will go infinitely smoother. Resist the urge to just sit down and bang out code. Many a project team has failed to do this and has blown the entire labor budget trying to patch and cobble something together only to ultimately step back, toss all the work done to date, and effectively start all over.

Once the design is complete, document it in a manner that is clear and unambiguous to the project team. The form of the documentation will vary depending upon the project size and type, but regardless, the documentation should be easily read and understood and easily updated as the project progresses to completion. This same documentation can be used for testing and checkout purposes at the end of the project and provided to the customer for future reference.

101 Tips for a Successful Automation CareerWatch-Outs: Due to tight schedules, many project managers encourage “concurrent engineering,” in which multiple teams are working simultaneously rather than sequentially. Fight the urge to let the programmers “get started” while another group is working out the software design details. If the programmers are allowed to begin in advance with no direction, much of their work product will ultimately have to be reworked or simply abandoned. When multiple people or vendors are part of project, spend extra time defining the boundaries where these groups interface. This is a common failure area of large projects.

Exceptions: Concurrent engineering is possible if it is done correctly. One portion of the design can be completed and released for detailed software development while the other areas are being designed and outlined. Keeping everything straight can be difficult, but it can work if the team communicates well.

Insight: This same advice is invaluable for writing a paper or creating a presentation. A simple outline will help focus the paper and make for a much more understandable document/talk. Start with a high level outline to list the concepts and the order of presentation, then add details to each section. Once a detailed outline has been created, converting it to a paper or talk is relatively easy because each line in the outline becomes a sentence or two in the final product.

Rule of Thumb: pro A sound outline or flow chart is a crucial first step for any paper, presentation, or software development project.

 

Hunter Vegas

About the Author
Hunter Vegas, P.E., holds a B.S.E.E. degree from Tulane University and an M.B.A. from Wake Forest University. His job titles have included instrument engineer, production engineer, instrumentation group leader, principal automation engineer, and unit production manager. In 2001, he joined Avid Solutions, Inc., as an engineering manager and lead project engineer, where he works today. Vegas has executed nearly 2,000 instrumentation and control projects over his career, with budgets ranging from a few thousand to millions of dollars. He is proficient in field instrumentation sizing and selection, safety interlock design, electrical design, advanced control strategy, and numerous control system hardware and software platforms.

Why Successful Automation Engineers Are Detail-Oriented

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. This is Tip #22.

101 Tips for a Successful Automation CareerI was working on a large automation retrofit project of a chemical plant that had numerous thermocouples scattered throughout the structures. A vendor suggested a particular thermocouple card that I had never used, and I was about to proceed with that card when I decided to quickly scan the specs on the card. There was an odd footnote about channel-to-channel isolation that caught my eye, and as I dug deeper into the details, I realized that channels 1 through 4 and channels 5 through 8 shared a common ground on the card.

Now, this plant was older and had a mix of grounded and ungrounded thermocouples. If I happened to get thermocouples from two different columns on the same group of channels, the resulting ground loops would have sent the readings all over the place. Luckily, I noticed this and was able to pursue a different path early in the design process.

Details matter—take the time to chase them.

Concept: If you are not a detail person, either pursue a different career or LEARN to be a detail person. The field of automation demands extreme attention to detail. Wire size, materials of construction, flange size, flange rating, min/max flows, temperature, pressure, etc.—the list goes on and on. Failure to evaluate even one item can have serious or even catastrophic consequences. Check and recheck everything— “good enough” can shut down a plant or even get people killed.

Details: Engineering is by definition a detail-oriented profession, but the field of automation requires almost fanatical attention to detail. Everything matters, which is why instrument spec sheets have so many lines on them. Engineers who just copy/paste spec sheets from a similar transmitter or use a control panel design without understanding it will not last long in this field. Automation is particularly challenging because the engineering skill set is so diverse. In the normal course of a job, automation engineers might find themselves doing mechanical design, electrical design, and chemical process design, and each of those has a long list of details to consider. Obviously, a comprehensive list of the necessary details in the field of automation would take multiple books to cover and cannot be provided here. However, here is a list of examples that will help you learn to chase the details:

• You should never copy or modify a design that you do not understand. A panel hardware design may involve a hundred design decisions—wires and I/O racks are sized for current and future needs, space is left for thermal dissipation, wireway is sized for current and future field wiring, locations for conduit penetrations are allocated, the cabinet is sized to fit in the room and even sized to fit through a particular doorway. If you copy that design and modify it without understanding what went into the original design decisions, you may quickly find yourself in trouble. The panel equipment may start overheating because a larger power supply was specified, or the main breaker may blow on start-up because the inrush currents are higher, etc.

• Read the specifications and understand them. Failing to consider the pressure/temperature limitations on instrumentation can have catastrophic consequences. Failingto look at the electrical details of I/O cards (grounding, leakage currents, voltage limitations, etc.) can turn a start-up into a nightmare. Looking at spec sheets might be the very definition of boredom, but FAILING to look at spec sheets may generate much more excitement than an engineer wants to encounter.

• Learn to color. Young engineers are notorious for working fast but missing details. One of the best ways to address this problem is to pick up a highlighter and learn how to color the lines as you work. If you are checking drawings, then highlight each section as it is completed. If you are doing an instrument takeoff, then color each instrument on the P&ID as it is added to the list. In short, find a document that covers everything that needs to be done, and color it as each item is completed. Checklists (such as those found at the end of this book) can also be an invaluable way to make sure everything has been considered and evaluated.

• Trust, but verify. After an engineering team leader has worked with a team for any length of time, he or she gets to know the strengths and weaknesses of each team member and knows where and to what degree back checking is required. New engineers should probably be 100% checked initially but can be backed off to spot checking once their skills are proven. However, even work done by seasoned engineers should be reviewed to some extent because everyone makes mistakes.

Watch-Outs: Always cross check vendor sizing calculations for instrumentation. Vendors often plug information into sizing software and generate impressive specifications and calculations, but they do not know the process, and they make errors. It is always worth running a rough cross check on their sizing and then reading through the entire specification to make sure the materials of construction are as required for the application.

Exceptions: None.

Insight: Many large engineering firms send a spec sheet with a smattering of process information to the vendors and let them generate the instrument specifications. This practice invites disaster. The vendor cannot possibly know the process details or the abnormal conditions that the instrument might encounter.

Rule of Thumb: Successful automation engineers HAVE to be detail-oriented. If this is not a natural tendency, then learn to color, cross check, or do whatever is required to be detail oriented.

 

Hunter Vegas

About the Author
Hunter Vegas, P.E., holds a B.S.E.E. degree from Tulane University and an M.B.A. from Wake Forest University. His job titles have included instrument engineer, production engineer, instrumentation group leader, principal automation engineer, and unit production manager. In 2001, he joined Avid Solutions, Inc., as an engineering manager and lead project engineer, where he works today. Vegas has executed nearly 2,000 instrumentation and control projects over his career, with budgets ranging from a few thousand to millions of dollars. He is proficient in field instrumentation sizing and selection, safety interlock design, electrical design, advanced control strategy, and numerous control system hardware and software platforms.

Benefits of Individually Fusing I/O with Indicating Fuse Blocks

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. This is Tip #20.

101 Tips for a Successful Automation CareerI recently encountered a control cabinet on a client’s site that had 50 valve-limit switches wired to a single breaker. If any of the 50 shorted, the entire group tripped off line. Between this installation and several others like it, the technicians often spent hours and even days trying to track down a single field wiring problem while the process equipment sat idle.

Concept: The small amount of extra money required to individually fuse I/O with indicating fuse blocks will be quickly recovered through dramatically improved troubleshooting. Even current limited I/O can benefit from individual fuses and/or disconnects.

Details: Troubleshooting a system that does not have individually fused I/O can be one of the most difficult and time-consuming activities for a technician. A single fault in the field can take out all the points on a card and might take out the entire cabinet. In such a case, the technician usually starts lifting wires and continually resetting the breaker until he or she finally isolates the problem. This problem can be avoided if the cabinet design incorporates individually fused I/O and indicating fuses. If the cabinet incorporates these features, the problem is immediately obvious the moment the door is opened. (The blown fuse light is difficult to miss.)

Unfused I/O is common in third-party skid packages where the vendor is trying to reduce costs wherever they can. Eliminate this possibility by specifying that all I/O must be individually fused with indicating fuses in the bid package.

Watch-Outs: In an attempt to add fuses, avoid the temptation to use two-, three-, or four-high terminal blocks to save room. These blocks look wonderful on paper but are AWFUL when they are installed in the field. The technicians cannot even SEE the lower terminals, much less get their probes on them for voltage readings, and the cabling is an absolute nightmare. Beware of I/O cards that purportedly include individual fuses. Almost none of these cards use indicating fuses and some of them require the entire card to be removed in order to replace one fuse!

Exceptions: Some I/O cards utilize current limiting circuits that can sustain a field short without damaging the card. In such a case, fuses are unnecessary, but consider installing terminal blocks with a built in disconnecting plug. Such a disconnect provides an easy means for the technicians to take series current measurements or connect their handheld communicators.

Insight: The increased cost of using individual fuses will be quickly recovered by the reduced time to troubleshoot and resolve field wiring problems. One or two instances of bringing production back on line within minutes rather than hours (or days) will easily pay for the initial installation.

Rule of Thumb: Individual, indicating fuses and single-high terminals take up more room in the cabinet, but the benefits far outweigh the costs. Build this into your standard cabinet designs and be sure to specify it in your third-party skid package specifications.

 

Hunter Vegas

About the Author
Hunter Vegas, P.E., holds a B.S.E.E. degree from Tulane University and an M.B.A. from Wake Forest University. His job titles have included instrument engineer, production engineer, instrumentation group leader, principal automation engineer, and unit production manager. In 2001, he joined Avid Solutions, Inc., as an engineering manager and lead project engineer, where he works today. Vegas has executed nearly 2,000 instrumentation and control projects over his career, with budgets ranging from a few thousand to millions of dollars. He is proficient in field instrumentation sizing and selection, safety interlock design, electrical design, advanced control strategy, and numerous control system hardware and software platforms.

The Value of Messaging in Industrial Control Systems

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. This is Tip #17.

101 Tips for a Successful Automation CareerThis is one of those tips that you cannot appreciate until you have worked on a control system that did NOT have adequate messaging programmed in it. Operators want to know what is going on, and system messaging is usually their only clue. Imagine running a complex or dangerous process and not having any feedback to tell you what is happening or if anything is happening at all! Or perhaps just as bad, imagine having the process sequence stop with such useless messages as “Sequence on Hold.”

Concept: Nothing frustrates an operator more than working on a control system that provides vague, generic messages, or worse, provides no clue that anything is happening at all. Tell the operator what is going on! If a phase goes to hold, the system should tell the operator why. If the system is on hold for 10 minutes, the operator should see a countdown. The extra effort to do this is minimal, and the positive impact on operations personnel is immeasurable.

Details: Creating detailed messaging is easy once the phase templates have been configured to include it. The messaging can be displayed in a two line message bar at the bottom of the screen that is used for active phase messaging and for operator questions and responses. Two lines are usually necessary because many batch processes have multiple operations occurring simultaneously and providing two message areas avoids overlap.

Here is a sample of some of the messaging an operator should see:

• During timed holds, the system should provide a countdown: “10 minute hold, 6:33 minutes remaining.”
• During material charges the message should indicate the amount and type of material charged and the amount remaining. For instance, the message might read: “Charging 200 gal caustic, 52 gal remaining.”
• If a phase goes to hold, the system should always indicate WHY it went to hold in a detailed manner. For instance, the message might read: “Rx 300 to storage transfer held due to high level in product TK 301.” Resist the urge to write generic messages such as “Phase on hold due to valve misalignment.” Indicate WHICH valve is the problem.
• During equipment setup, the system should indicate what actions are being performed. For instance, the starting of an agitator might generate these messages: “Starting Agitator,” “Ramping speed to 75%,” “Agitator at Speed” etc. Generic messages such as “Setting Up Equipment” do not give much indication of what is happening.

Take the time to do messaging right. The improved operability and increased information to the operator will reduce downtime and allow the operators to quickly identify problems and resolve them without outside maintenance and/or engineering help.

Watch-Outs: If a programmer is not a good speller, do not have him or her doing the messaging! A couple of misspelled words will dramatically lower the perceived quality of the control system in the operator’s eyes. (See Appearance Matters Tip #30.)

Exceptions: There aren’t any. Even a simple sequence can be programmed with a short message bar that is populated as logic is executed.

Insight: A trick to making messaging easy is to create one (or two) operator message variables that appear in the message lines on the bottom of the page. The various phases write to these variables so that the operator gets used to seeing phase related messaging in the same place. These message bars can be placed on several graphics as appropriate.

Rule of Thumb: Messaging can make or break a control system. If the information is detailed and useful, the operator will be able to run the system much more independently and resolve problems without any outside help. If the messages are generic or non-existent, Operations will be calling Engineering all night long looking for help to identify problems and get the process running again.

 

Hunter Vegas

About the Author
Hunter Vegas, P.E., holds a B.S.E.E. degree from Tulane University and an M.B.A. from Wake Forest University. His job titles have included instrument engineer, production engineer, instrumentation group leader, principal automation engineer, and unit production manager. In 2001, he joined Avid Solutions, Inc., as an engineering manager and lead project engineer, where he works today. Vegas has executed nearly 2,000 instrumentation and control projects over his career, with budgets ranging from a few thousand to millions of dollars. He is proficient in field instrumentation sizing and selection, safety interlock design, electrical design, advanced control strategy, and numerous control system hardware and software platforms.
Automation Career Tip: Too Many Alarms Can Be Worse Than None at All

Automation Career Tip: Too Many Alarms Can Be Worse Than None at All

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. This is Tip #21.

101 Tips for a Successful Automation CareerAt one time, I worked in a large continuous process plant that had alarms coming in constantly. The operators could hit the “Silence” button in their sleep. We had a case where a process flow was accidently diverted to the wrong tank, and it eventually filled and overflowed the tank. Even though the tank had redundant level transmitters and we had one of the more alert panelboard operators on shift, the rising level was not noticed until the tank overflowed and was noticed by a field operator. The panelboard operator had silenced two high alarms, two hi-hi alarms, two “over” alarms, and two range alarms over the course of two hours but had failed to recognize that there was a problem.

Concept: Enable alarms on instruments that matter and on process non-conformances that the operator can do something about. Having alarms for the sake of having alarms only ensures that ALL alarms will be ignored—even the ones that matter.

Details: Alarm management has become all the rage lately, and with good reason. The proliferation of instrumentation busses has provided access to a plethora of information, and because everything is now typically alarmed, the operators are being buried under a barrage of alarms. When faced with a constant stream of annunciation, most operators quickly become numb and increasingly just hit “Silence.” Critical alarms are lost in the noise and are routinely missed.

Ironically, there was an advantage to the relay annunciator panels built into the old control room panelboards. There were only so many points available, so only the critical alarms made the list. With the advent of computers, EVERYTHING can be alarmed, and unfortunately that is exactly what happens.

An engineer has several ways to address this problem, and many books have been written on the subject. Addressing this expansive topic in a few pages is not possible, but here is a brief list of suggestions that can help reduce the problem of too many alarms.

• Enable alarms on instruments that matter.
• If an operator cannot do something to resolve the situation, there is no point in alarming it.
• Program “smart” alarms. Automatically disable alarms on out-of-service equipment. Add conditional logic that generates a common alarm when a piece of equipment trips rather than generating 10 or 15 alarms that essentially indicate the same condition. (For instance, if a boiler trips it makes little sense to alarm the trip, low gas flow, low gas pressure, low air flow, etc.) One piece of information that IS useful, however, is “first out” trip information. Many operators use the alarm list to determine what tripped the equipment. If the first out information can be indicated on a graphic, the operators do not need to see the individual alarms.
• Segregate the alarms and deliver the information to the appropriate audience. The operators do not need to see most calibration and/or maintenance alarms, but the maintenance department does. Generate an alarm report to Maintenance, but just indicate a possible problem to the operator so he or she can be aware of it.
• Change from alarms to indicators. If a process is running out of spec but not in a critical range, then it may make more sense to indicate this condition as a color change on the graphic instead of than firing an alarm that must be acknowledged.
• Monitor alarms and routinely eliminate “bad actors.” In most cases, a large percentage of alarms is created by a handful of points. An occasional review of the most active alarms will allow the plant to identify these points and modify the programming to reduce their frequency or address their cause. Doing this can dramatically reduce the total alarm count without requiring much effort.

Watch-Outs: Many control systems default to having all the alarms enabled. On a new system, it may make more sense to enable none of the alarms initially and add them back as necessary.

Exceptions: Some plants do not allow the operators to suppress alarms because they are concerned that critical alarms will be turned off and never restored. One solution to this problem is to allow operators the ability to suppress alarms, but program the alarms to automatically restore after some appropriate period of time. In this way, a broken instrument can be silenced for a shift while repairs are made.

Insight: One plant only enabled setpoint alarms when a controller was in automatic. (Such alarms annunciate when the process variable is beyond the allowable range around the current setpoint.) High and low alarms were not enabled unless the controller was in manual. This method provided increased alarming when a loop was in manual but did not generate alarms on a point in automatic unless it deviated too far from setpoint.

Rule of Thumb: Alarm management is a never ending effort. Routinely review the plant’s alarm list, and try to eliminate or address points that appear too often. When configuring new systems, include some means of smart alarm management into the design.

 

Hunter Vegas

About the Author
Hunter Vegas, P.E., holds a B.S.E.E. degree from Tulane University and an M.B.A. from Wake Forest University. His job titles have included instrument engineer, production engineer, instrumentation group leader, principal automation engineer, and unit production manager. In 2001, he joined Avid Solutions, Inc., as an engineering manager and lead project engineer, where he works today. Vegas has executed nearly 2,000 instrumentation and control projects over his career, with budgets ranging from a few thousand to millions of dollars. He is proficient in field instrumentation sizing and selection, safety interlock design, electrical design, advanced control strategy, and numerous control system hardware and software platforms.

Always Design in Spare Capacity to Allow for Industrial Plant Expansion

The following tip is from the ISA book by Greg McMillan and Hunter Vegas titled 101 Tips for a Successful Automation Career, inspired by the ISA Mentor Program. This is Tip #19.

101 Tips for a Successful Automation CareerOver my career I cannot think of a single time when I regretted running spare cables or oversizing field junction boxes. However, I can think of too many instances where I ran out of room and/or capacity much sooner than I had expected, and wished I had run MORE spares.

Concept: The incremental purchase cost of a 36 pair cable over a 24 pair cable is practically negligible when compared with the labor cost of running either cable. Install spare wire capacity whenever possible, or at least plan for future expansion when sizing junction boxes, cable trays, and control system I/O.

Details: During system design, always run spare cable, oversize the field junction boxes, and buy extra I/O cards. Ideally, the cost of this spare capacity can be worked into the project cost during the estimating phase so the money will be available when the project is approved. Even if the spare capacity was not included in the original budget, the additional cost of adding the extra capacity is usually low enough that it can be incorporated with no significant impact on the budget. If the project budget is so tight that larger cables or spare capacity cannot be installed, at least PLAN for future additions. Install slightly bigger field junction boxes and cable trays so that more cables can be added later. Oversize conduits, and leave a draw string in them so wires can be pulled in on future projects. Leave blank spaces in the I/O cabinets so I/O racks can be added later, or at least leave space in the room so I/O cabinets can be installed in a future project.

This concept is particularly true when running fiber optic cable. The labor to run a 6 fiber, 12 fiber, or 24 fiber cable is essentially the same and the material cost difference is low. Running a cable with less than 12 fibers is pointless, and if expansion is even slightly possible, run a 24 fiber cable.

Watch-Outs: Always ask about future expansion plans during the design phase of an automation project. By knowing how the ultimate system might appear, you can make minor design changes that will make future growth much less costly and difficult. If the system will double in size, you can lay out the I/O cabinets, power supplies, etc. in such a way that they can be easily upgraded in the future without burdening the current project significantly.

Exceptions: Occasionally an automation project involves a machine or a process that is so mature that future expansion is unlikely. This is not a common occurrence, but if this situation applies, clearly the cost of adding spare capacity would not be justified.

Insight: Project managers hate adding spare capacity after the project has been approved because they consider it “scope creep” and not part of the project. Plants adore spare capacity because it allows the execution of process improvement projects at a much reduced cost. In the long run, the company certainly saves money, but the project manager is not nearly as concerned with the long run as the execution of his or her project. If the spare capacity is included in the original project estimates, then all parties win. The project manager is happy because the project scope has not changed, and the plant and company are happy because they can expand in the future at a much reduced cost.

Rule of Thumb: A common rule of thumb for most systems is to add at least 25 percent spare capacity to the original design. Depending upon the future plans of the plant, a higher percentage might be justified. Adding less than that figure is usually not advisable unless the plant and/or process are mature and unlikely to change.

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