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Flying by the seat of your pants?

Tue, 18 Jun 2013 08:05:00 -0400

There was a time in the history of aviation when “flying by the seat of your pants” had real meaning given the relative lack of gages in an early airplane’s cockpit. Yet, in many ways we still operate our plants this way. We instrument what we consider to be critical measurements based on historical operation, but we don’t necessarily perform a detailed analysis of the process to determine if there are other things that might be just as important to the operation in terms of throughput or quality or, possibly even more importantly, to uptime and equipment longevity. Even those organizations that don’t have a “run it till it breaks” mentality don’t necessarily make the best use of the instrumentation they have, while more thoughtful companies install things that could be beneficial in improving uptime and operation of the facility.

While there’s something to be said for the ability of the human body to detect small changes in things, like vibration or the sound of a piece of equipment, there’s no substitute for good measurement to detect it before it becomes bad enough for a human to detect. Heuristic capabilities built into some instruments have extended this human capability for sensing problems so they can be detected well before an operator can. One manufacturer, for example, has built a plugged sensing line detection capability into their transmitters that uses the noise signature of the process. When it decreases by a threshold amount, it generates an alarm. Sensing these changes in process noise can also be used to detect other problems like pump impeller wear, which can also create pressure fluctuations that then cause a valve to cycle excessively leading to an early failure. Digital valve positioners can analyze the motions of the valve that would go unnoticed by an operator to alert maintenance to the need for service before the valve fails. This use of heuristics can be applied to any number of other situations to prevent failures before they happen.

So why aren’t more plants taking advantage of these kinds of diagnostic capabilities? The problem is that organizations are in many ways constrained either externally or internally from deploying these technologies. One key constraint is financial. Some of what’s required to perform the analysis falls into the realm of capital expenditures, which in most cases requires a payback. If the system does its job so you keep from having the outage and down time that would have cost you the money you justified buying it on, then without the down time you can’t show that you actually saved any money, making the successful system a failure. Talk about a “Catch-22.” Another constraint is cultural. One engineer for a major U.S. corporation has said that his company won’t buy some of these technologies because to use them effectively would require rewriting their maintenance procedures, which they won’t do. A competitor of theirs has stated that having the plugged line sensing technology would have prevented an explosion that occurred at one of their refineries. That means the first company is unwilling to install something that would prevent an explosion because they would have to change a procedure that is meant to prevent explosions. Really? What Catch-22s have you run into that have prevented you from implementing something that logically should have been implemented?

This post was written by Bruce Brandt. Bruce is a technology leader at MAVERICK Technologies, a leading system integrator providing industrial automation, operational support, and control systems engineering services in the manufacturing and process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems, manufacturing execution systems, operational strategy, and business process optimization. The company provides a full range of automation and controls services – ranging from PID controller tuning and HMI programming to serving as a main automation contractor. Additionally MAVERICK offers industrial and technical staffing services, placing on-site automation, instrumentation and controls engineers.

Machine Safety: For a safe machine, I’ll just install a small safety PLC

jb@jbtitus.com — Mon, 17 Jun 2013 06:59:00 -0400

“Have you heard the one about a manufacturing plant discussing options on how to modify an existing machine’s architecture and how to mitigate a hazard? They’re actually evaluating someone’s plan to install one small safety PLC for this hazard and to slave the other distributed standard PLCs to the safety PLC. Therefore, we won’t have to do a risk assessment of the whole machine and we’ll be in compliance”! This is not a joke! I’ve seen this story unfold multiple times over the past 10 years. An applications approach as described above does not attempt to identify all hazards and mitigation plans on a machine. And, I would argue that the machine is completely unsafe. A complete solution following a risk assessment could involve:

Redundant components, sensors, actuators, etc.
Safety certified components to different Cat levels
Redundant cabling
Additional state monitoring
Safety certified software
Validation & documentation
An updated risk assessment
... and more.

It is commonly understood today that a risk assessment forms the foundation for design / modification. All hazards need to be identified and mitigated on a machine one by one to acceptable levels. Okay, there are some folks out there that simply require a machine (and all of its hazards) to be mitigated to meet one Category, such as Cat 2 or Cat 3. When this happens a risk assessment is still required and many of the hazard mitigation solutions could well be over-engineered with a costly investment. Is there any valid excuse for not performing a risk assessment today? No! Machine standards and regulations do not provide conditions on how to avoid completing the required risk assessment for each machine. And, simply slaving existing standard PLCs on a machine to a safety PLC does not meet the requirements for the safety related parts of a control system (SRP/CS). Or more simply said, it does not meet the requirements for the safety-related circuits! Has this presented you with any new perspectives? Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below. Related articles: Machine safety risk level assessment priority: Possibility, severity, or frequency? Machine Safety: functional safety and the steps to be compliant in the US. Machine Safety – OSHA’s Top 10 Violations for 2012 Machine Safety: Is OSHA okay with my 'acceptable' risk mitigation? Contact: http://www.jbtitus.com for “Solutions for Machine Safety”.

Machine Safety: Actuator controls versus machine actuators

jb@jbtitus.com — Wed, 12 Jun 2013 09:25:00 -0400

Why is knowing the difference between a machine actuator versus an actuator control important? The hazard on a machine is what’s really important to reducing risk! What is the hazard? Motion caused by a machine actuator can be a hazard to an operator, maintenance technician, set-up engineer, or clean-up personnel, to mention a few. However, the power (electrical, hydraulic, pneumatic, etc.) applied to the actuator control also can be a hazard to the same personnel. So, is looking at the hazard the best way to understand these terms? Perhaps some definitions of these two terms may help clear up the confusion. Several international and domestic standards define:

An actuator control as an operator control device used to initiate or maintain machine motion or other machine function(s). Some examples given include; two-hand control, treadle bar, foot control, inching button, e-stop device, etc.
A machine actuator as a power mechanism used to cause motion of a machine. Some examples given include; air cylinder, motor starter, hydraulic valve, etc.

That said (and not to add more confusion) the machine safety standards also explain that a PSD (presence sensing device) device is an example of an actuator control. An example is when the robot arm retracts from a light curtain field initiating a signal to the machine control system to automatically cycle the machine. Or, when a “safe drive” automatically detects a fault and causes a Cat 1 machine stop. Where’s the operator in these examples? Regarding machine actuators, I’ve also seen the metal rod inside an operator control device described as an actuator because it causes the contact(s) to open and remove power. Therefore, can a machine actuator also cause the stopping of a machine motion as well as causing machine motion? What about the friction clutch in a mechanical power press? Is this device a machine actuator since it either causes or stops motion and is powered via electric, hydraulic, pneumatic or spring type energy? I believe by now the answer might be as clear as mud. So, what’s the point? It’s my opinion that this discussion is a good example where industry experts can help interpret the intent and requirements of machine safety industry standards. After all, has anyone ever seen a prescriptive Standard for compliance? Has this presented you with any new perspectives? Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below. Related articles: Inside Machines: Does adopting ISO 13849-1:2006 change the U.S. model for compliance and enforcement? Machine Safety – does OSHA reference consensus standards for compliance? Machine Safety: Is OSHA okay with my 'acceptable' risk mitigation? Contact: http://www.jbtitus.com for “Solutions for Machine Safety”.

Exceeding expectations And/Or destined for failure

Mon, 10 Jun 2013 17:20:00 -0400

Is your control system exceeding expectations by performing in an environment for which it is not rated, operating beyond its rated temperature, powering loads beyond the documented capacity, or is it destined for failure? So which is it, or is it more than one? In most cases where an issue is present, the answer is yes to more than one, including the last one: the equipment is functioning beyond rated capacity and destined for failure, yet the owner is unaware.

Over the years I have seen too many instances of control equipment being used beyond its documented limitations and expiring prematurely. Of course, when the equipment does fail it will likely be at the most inconvenient and costly time possible. Using equipment beyond its documented limitations either knowingly or in most cases out of ignorance, will result in premature equipment failure which translates into downtime and ultimately increased cost of ownership. Most all equipment and certainly all UL certified equipment has published temperature, temperature derating, voltage, current, and environment (NEMA) ratings applicable to the equipment. A UL certified control panel is a good start, but it’s not a guarantee and it’s not enough. Adhering to good design standards and practices which ensures the limitations of the equipment are not exceeded, followed up with a good internal quality control system is the recipe for developing a control system with a lower cost of ownership which can live up to the runtime hours and/or cycles published by the manufacturer.

Do you have a new project on the board, or a control system which tends to be a trouble maker and requires constant maintenance? If you plan to seek outside help, make sure you start down the right path and inquire about the company’s engineering standards and practices. Here are my top five suggestions to make sure your next control system design is going to meet your needs for years to come:

1. Ensure your supplier has good processes and standards around component selection taking into account electrical and environmental requirements.

2. Ensure your supplier has standardized procedures for preparing design deliverables such as control system cabinetry, instrumentation, etc. This might include instrument data sheets, heat calculations, power (load) calculations, and standardized drawing packages that are easy to read and facilitate future troubleshooting by operations.

3. If your company has standards, be sure your supplier is flexible enough to adopt them.

4. Ensure your supplier has robust quality control procedures to catch design errors before equipment is purchased and assembled, or worse yet, delivered to your facility.

5. Ensure your supplier is capable of meeting your facility’s area classification requirements. Look for suppliers who can supply UL 508A listed panels for normal situations or UL 698A listed panels for classified areas.

This post was written by Andy Crossman. Andy is a control system specialist at MAVERICK Technologies, a leading system integrator providing industrial automation, operational support, and control systems engineering services in the manufacturing and process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems, manufacturing execution systems, operational strategy, and business process optimization. The company provides a full range of automation and controls services – ranging from PID controller tuning and HMI programming to serving as a main automation contractor. Additionally MAVERICK offers industrial and technical staffing services, placing on-site automation, instrumentation and controls engineers.

Create value with re-use

Mon, 10 Jun 2013 06:54:00 -0400

How much re-use are you getting out of your projects? In other words, when you finish one project what parts can you directly apply to the next? As a specific example we often ask the question:

· How many projects can a great Functional Design Specification (FDS) affect before the start of a project:

o One

· How many projects can a great FDS effect after the project if time is taken to complete the as-built document, add screen-shots with callouts, and file with an appropriate version number in a public space for sharing?

o 10? 20? Many

Why then do so many projects drop the ball after the project is complete and walk away without working to catalog what was built, the standards used (and improved) and where and how that work could be applied in future. Not-invented-here syndrome is a common challenge in system integration (and engineering in general) but if we can get move past this the potential for both individual project success as well as long term growth of the integration industry is huge. As a summary, the chart details the integration project costs (both as dollar and percentage values) for a two-plant install between continents. The Plant 1 design and implementation contributed directly to Plant 2. All efforts listed represent direct integration costs only.

Further to the direct integration benefits of re-use, client-centric benefits include:

· Lower project risk – Components identified as new/different are noted as risk factors and engineering effort is spent up front mitigating that risk. As an example, a set of pre-built VM servers that can be re-used from project to project will lower the risk of incorrect software install order, unsupported patch installations, or other configuration errors, which can result in longer setup and commissioning time.

· Lower support cost – If the same standards are used across multiple sites or lines, the net training effort required for the organization drops significantly. As an example, a video-recorded training presentation which outlines application navigation and troubleshooting can be created and viewed in multiple plants and multiple languages with only one investment in content development.

· Lower threshold for improvement – as an improvement is identified it can be quickly copied from one plant to another. As an example, a recipe improvement in one plant could be electronically submitted to another for next-day business return on investment (ROI).

· Lower per-project design cost – Re-using software from one project to another has a direct, positive impact on business project management costs such as the total time required by H.B. Fuller employees in software reviews (43 vs. 2 as outlined in previous graph)

In summary: change your focus. What you do after commissioning should be held in as high regard as what you do before. - Anthony Baker strikes again: Anthony Baker is a fictitious aggregation of experts from Callisto Integration, providing manufacturing consulting and systems integration. This blog provides integration advice in plant-floor controls, manufacturing execution systems (MES), and manufacturing consulting, from the factory floor through to the enterprise. Andrew Barker, P.Eng., Callisto Integration, compiled the advice. www.callistointegration.com

Machine Safety: Are you farming out the designing in of functional safety component requirements?

jb@jbtitus.com — Thu, 06 Jun 2013 07:02:00 -0400

With all the chatter on the internet and in the media a new subject arises regarding functional safety. Are automation suppliers truly considering farming out the design and safety certification effort of integrating functional safety features into existing components? Well, it seems that there are some engineering firms which are specializing in this capability and offering these services to various automation suppliers. This strategy appears to be partly based on various factors: 1. Market demand has increased for automation products with functional safety features. For example, drive systems with safe stop, safe torque off, etc. safety functionality built in. 2. Time to market can be shortened by utilizing experienced qualified engineering firms to provide these services. 3. Automation companies typically incur incremental costs to grow specialized internal safety certified organizational know-how to perform these services. 4. Increased market demand comes from an increasing awareness of reduced life cycle costs of ownership through “safety automation” versus hardwired safety applications. You probably say, "Great stuff!" Right? Caution: Don’t be too quick to run to the bank. As an end user, just because your favorite automation supplier quickly brought you a safety certified component doesn’t necessarily mean they’re capable of full service to you as their customer. Farming out the design and certification effort is only one spoke in the wheel of resources required by automation suppliers to support their safety automation products. To mention a few; they will also need pre-sales support, post sale service support and training support. You wouldn’t want to phone your automation supplier’s 24 hour hot line only to be transferred to their engineering firm sub contractor (for functional safety) to then leave a voice message. After all, reducing unplanned machine downtime was supposed to be part of your return-on-investment decision. So, you might want to ask your favorite automation supplier a few questions related to the topics above before deciding. Has this presented you with any new perspectives? Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below. Related articles: Inside Machines: Does adopting ISO 13849-1:2006 change the U.S. model for compliance and enforcement? Machine safety: Incorporating functional safety as part of your machine safety plan, Part 4 Machine safety and functional safety: Which type? Machine Safety: functional safety and the steps to be compliant in the US. Contact: http://www.jbtitus.com for “Solutions for Machine Safety”.

A few tools for continuous improvement

Mon, 03 Jun 2013 15:43:00 -0400

These days everyone has a continuous improvement program of some kind. Six Sigma is used quite extensively as is Lean Manufacturing. Some companies stick to one approach while others tailor their own programs using the best ideas from a wide variety of different sources.

Regardless of whichever particular flavor of continuous improvement program you use, it seems there’s always more to do. There are always more problems to tackle.

Once you solved one problem, another problem seems to pop up to take its place. But, after all, it’s a continuous improvement program so there’s always going to be more to do.

But, there are some things that can help and some tools that work really well that are geared specifically for continuous improvement programs. These tools can make a significant impact in a program and can help people working in the programs do a lot more and solve a lot more problems.

Data collection

One category of tools is data collection. The idea here is that to analyze a problem, you need lots of hard data about the problem. Guesses just won’t do. You have to know what’s actually going on. There are a lot of different ways that you can implement data collection, but the key is to get all the data you need and store it in a way that people can use.

DCS and PLC systems are great sources of data and are usually part of any data collection system. Networking is required to get the data from one place to another. And, some type of storage solution such as a data historian or general purpose database is also necessary.

Dashboards and reports

Once you have the data collected, you really need to get the data to the right people so that they can do something with it. There are lots of ways to do this and lots of ways that this can work, but the objective is just to get the data out to the people who need it.

Some people hate the word dashboards and some people love the word, but the analogy is so straightforward that it needs no explanation. There are lots of dashboard and reporting solutions out there, but the key is that they tie back to the data historian and the database and allow all the right people access to the data that they need, when they need it, and in the way that they need it.

Analytics

The idea of analytics is pretty simple. The first steps are always getting the data and then just having access to the data. Analytics takes it all a big step further by providing tools to analyze the data, slice and dice the data, look at large volumes of data, and otherwise mine the data to get the real information and the real understanding out of it all that you need.

Analytics can be a lot more than just looking at data or even developing complex reports. Analytics is all about taking the data apart and putting it back together to see trends and relationships that you never knew about before and gaining a much deeper understanding of what’s actually going on in the real world.

Metrics

The idea of metrics takes a slightly different approach to things. The idea here is to define the key data that indicates the true performance of the manufacturing operation or process. Based on this idea, many people refer to metrics as key performance indicators. The idea is not merely to look at the data or even just analyze the data, but to identify and monitor the data elements that tell you how well the operation or process is actually running.

The important point here is that you have to get beyond the data to the specific measures of the operation or process. And, the measures need to indicate how well the operation or process is actually running, which is a lot more complicated that just how fast the machine is running or how many units are being produced per hour.

OEE

OEE, or overall equipment effectiveness, is one specific metric that has become a staple in a lot of continuous improvement programs around the world. OEE attempts to measure not merely how fast a line or piece of equipment is running but its true manufacturing performance.

OEE does this by combining three metrics which are typically calculated using a lot of underlying data. Availability is calculated based on runtime and downtime. Performance is calculated based on actual versus theoretical rates. Quality is calculated based on actual first-pass quality. Together, availability, performance, and quality make up OEE and provide a very good standard approach to measuring the true performance of a manufacturing line or process.

Statistics

A specialized version of general analytics is statistical analysis. Statistical analysis in manufacturing usually takes the form of SPC (statistical process control) or SQC (statistical quality control). The short definition of SPC/SQC is the application of statistical methods to control manufacturing process or control manufacturing quality.

SPC/SQC is very valuable in manufacturing because the various statistical analyses can help you anticipate problems and avoid them before they really become problems. The statistical methods allow you to analyze trends in real-time and take corrective actions to prevent situations from becoming problems.

Conclusion

We’ve gone through a lot of ideas pretty quickly. But, you should be able to see that there are a lot of tools out there to help you with your continuous improvement program. These tools work really well and are geared specifically for continuous improvement programs. And, they can make a significant impact in a continuous improvement program. They can help the people working in the programs do a lot more and solve more problems. When you get a chance, take a close look at these tools and see if you don’t think that they can help your continuous improvement program.

This post was written by John Clemons, PE. John is the director of manufacturing IT at MAVERICK Technologies, a leading system integrator providing industrial automation, operational support, and control systems engineering services in the manufacturing and process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems, manufacturing execution systems, operational strategy, and business process optimization. The company provides a full range of automation and controls services – ranging from PID controller tuning and HMI programming to serving as a main automation contractor. Additionally MAVERICK offers industrial and technical staffing services, placing on-site automation, instrumentation and controls engineers.

Baseline your system or else

Mon, 03 Jun 2013 12:24:00 -0400

Anthony’s customer required an architectural change to a control system to support some new functions, a conversion from a two PLC (programmable logic controller) system to a three PLC system. All the old interlocks were mapped and moved, and new interlocks added between PLCs. All the DA (data administrator) servers, Invensys Wonderware ArchestrA objects and Wonderware InTouch HMI software tags were reconfigured for the new setup. In short, all items in the checklist were complete. The new architecture was installed Saturday morning, and a whole bunch of test cases were run over a three-day weekend, to make sure everything was still working, and to tweak all of the control timing for the new response time. Everything looked good, so Monday night, it’s time start-up production again. And everything looked good in production too; just some minor tweaks here and there. Not everything can be caught in testing, so this was expected. Non-specific trend On Tuesday evening the client appears: Client: “We’re getting more products not sent to the right location.” Immediately questions start running through Anthony’s head:

What could be causing this?
Are there mechanical issues?
Is the system not setup correctly?
Is there a communication or network issue? I think that has that happened before.
Why hasn’t this been brought up earlier? It looks like everything is running just fine.

After looking around for some possible causes, Anthony can’t really identify anything that is causing this issue. Client: “We are still seeing more products showing up in incorrect locations.” Anthony: “I can’t really find any issues, how much more product?” Client: “More than before. We usually get 120/160/180 per shift, and now we’re seeing 160/180, but last shift we got 300.” Anthony: “Well 300 seems like a lot more than usual. Something else must have gone wrong.” Client: “Maybe it did. I don’t know really. I just know we’re seeing more than before these changes were put in.” Moving target By this point Anthony is tearing his hair out trying to find the problem. Anthony’s manager: “You’re spending a lot of time on this. How are we going to know when we’re done?” Anthony: “I don’t know. I’ve fixed a bunch of things that would have existed before the change, but they keep telling me that it’s more than before, or it’s too much in general.” Anthony’s manager: “If now it’s too much, how much is right? 100? 50? 0? What’s the target here? Do we know for sure what they had before?” Anthony: “I don’t know. They don’t have historical data. I heard one guy say six per shift was expected...” This continued until all ideas were exhausted, along with Anthony. In the end, it got down to a count under 30 per shift, much lower than it was before, and the client was happy. Anthony fixed some things that had been in the code since nearly the beginning of the project, but hadn’t come up before. Lessons learned If you’re going to be making a change or improvement to a system make sure you have the baseline data on how it operated before, in production. Your test cases won’t always show all the problems on a complex system. - Anthony Baker strikes again: Anthony Baker is a fictitious aggregation of experts from Callisto Integration, providing manufacturing consulting and systems integration. This blog provides integration advice in plant-floor controls, manufacturing execution systems (MES), and manufacturing consulting, from the factory floor through to the enterprise. Andrew Barker, P.Eng., Callisto Integration, compiled the advice. www.callistointegration.com

Machine Safety: Robotic Industries Association updates safety requirements for robots

jb@jbtitus.com — Sat, 01 Jun 2013 12:28:00 -0400

Robotic Industries Association (RIA) announced its updated ANSI/RIA R15.06-2012 standard for robotic safety. This is the first update since 1999 and it is now harmonized with the international standard ISO 10218:2011. “Approved March 28, 2013. A revision of ANSI R15.06-1999, this standard provides guidelines for the manufacture and integration of Industrial Robots and Robot Systems with emphasis on their safe use, the importance of risk assessment and establishing personnel safety. This standard is a national adoption of the International Standards ISO 10218-1 and ISO 10218-2 for Industrial Robots and Robot Systems, and offers a global safety standard for the manufacture and integration of such systems.” Wow, this is a major step forward for both robot manufacturers and users of robots in factory applications here in the US. It looks like this advancement means a departure from the previous seven risk reduction categories of; R1, R2A, R2B, R2C, R3A, R3B & R4 to the five Performance Level (PL) designations of PLa through PLe. Category levels (B, 1 --- 4) will be re-defined following ISO 13849-1: 2006 and applied for the architecture structure. These changes and others will definitely be improvements for robot manufacturers and systems integrators.

Control Engineering April cover

story on robotics includes more

about robotic safety.

To take a step back - does this mean that all of the additional requirements from ISO 13849-1 for “designers” will likewise be required for compliance to the updated ANSI/RIA R15.06-2012 standard? If so, I guess the robot manufacturers, systems integrators and some end users, all of which have “designers,” will find a way to comply with the additional requirements. From an enforcement model comparison this seems to fall directly in line with the European Model. But, as I’ve previously blogged, what about the other half of industry here in the U.S., which doesn't have “designers” in their businesses? And, the U.S. enforcement model (OSHA) places the first responsibility for safety on the end user of machinery in contrast to the European model. If these end users (without designers) could follow 15.06: 1999 for compliance with OSHA will they also be able to follow 15.06: 2012? If the answer to this question doesn’t have an easy answer, then what’s happened? It’s been my experience that U.S. standards bodies are reluctant to add new heavy requirements to “all” users of their standard in order to meet the overall intent of the updated standard. Is OSHA going to adopt the European enforcement model? Can anyone help us out with this over-arching question for “all” user compliance? Has this presented you with any new perspectives? Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below. Related articles: Inside Machines: Does adopting ISO 13849-1:2006 change the U.S. model for compliance and enforcement? http://www.robotics.org/content-detail.cfm/Industrial-Robotics-News/New-Robot-Safety-Standard-Approved/content_id/4118 Machine Safety - updating ISO 13849-1 compliance for robots. Updating Minds About Machine Safety Machine Safety – does OSHA reference consensus standards for compliance? Contact: http://www.jbtitus.com for “Solutions for Machine Safety”.

Growing the next generation

Tue, 28 May 2013 10:03:00 -0400

A lot has been written lately about the shortage of candidates for positions in the process control field and how we’re going to grow the next generation of process control engineers and technicians. As with a lot of other careers, companies have grown accustomed to being able to pick and choose between candidates in recent years. That is coming to an end as more and more of my contemporaries finally decide to retire and as more and more of the installed base of control systems become terminally obsolete. Corporations have also gotten used to doing more with fewer people. The problem is that those they kept have their hands full just keeping things running. There’s no time to teach new people how to do the work.

We’d like to believe that if we just hire from the right engineering disciplines that we won’t have to train, but the reality is that the curricula in our universities do not teach much of what’s needed in the practical application of process control to a single discipline. Chemical engineering grads have been exposed to process design, so they have the tools to do some of the work, but if they’ve been exposed to process control, it is generally a theoretical approach. If the ChEs have been exposed to the electrical engineering curriculum, it amounts to just that, exposure. Electrical engineering grads are to some degree even more disadvantaged because if they’ve taken a controls course, it has focused on servo control and again the theoretical approach of Laplace transforms and Bode plots. The EE grads often have the added disadvantage of very little exposure to industrial processes. They may or may not get exposed to high voltage devices, thermodynamics, and fluid mechanics, though they may take survey courses of these topics. Mechanical engineers are in a similar boat as EEs since they may or may not get any process engineering along with their courses in fluids and thermodynamics and will have only taken an EE survey course and a freshman chemistry course.

Being a mechanical engineer, I had to learn how to design control circuits properly including motor control circuits. That included understanding issues around proper grounding techniques, which became even more problematic with the early DDC and DCSs because of their sensitivity to noise. I also had to learn proper methodology for installing instrument impulse lines, something no conventional curriculum teaches, nor do they teach how to select measuring devices. Which curriculum teaches you why you should always start large fans against a closed damper? Which teaches you why the pressure and flow measurements in the boiler’s main steam line should always come off the side of the pipe? Which teaches the advantage of a thermocouple over an RTD that has nothing to do with accuracy or range? (Hint: which one can be “fixed” with a hammer at 2:00 am?) Which teaches the design of failsafe circuits? These are the kinds of things that I mean when I speak of the practical application of process control. Such things can only be taught effectively on the job and, in some cases, through direct experience of what happens when you do it wrong.

So, what are your arcane bits practical process controls that you’ve learned over the years? What do you think is the best way to impart those gems of knowledge to the next generation? How can you convince your company that they have to train new grads on more than the company culture and HR policies?

This post was written by Bruce Brandt, PE. Bruce is the DeltaV technology leader at MAVERICK Technologies, a leading system integrator providing industrial automation, operational support, and control systems engineering services in the manufacturing and process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems, manufacturing execution systems, operational strategy, and business process optimization. The company provides a full range of automation and controls services – ranging from PID controller tuning and HMI programming to serving as a main automation contractor. Additionally MAVERICK offers industrial and technical staffing services, placing on-site automation, instrumentation and controls engineers.