Casually surfed over to ISA with a thought of joining - until I saw that the standards will cost you USD9.50 each and only available in batches (subscriptions) of 10. That is besides the membership fee.
At least they tried to hide it by stating that members could buy an unlimited amount of subscriptions. Wow, great, way to go.
This reminds me of profibus. You go to these instrumentation shows and they have all different OEM equipment hooked to this silly purple cable. "Great", I thought. Until I tried to hook a Siemens HMI panel to a Mitsubishi Q3-series via profibus DP. Last OEM quote was Euro77000 to write a driver for the Siemens PROFIBUS panel. So much for open source and interconnectivity. Like ISA, it's all about the money.
Is getting the standards the only reaon you can think of for joining? Can you see the the standards in libraries? Are people supposed to work for no money? Did you fix the Siemens - Mitsubishi interface problem? Did you get paid? There is a reasonable discussion to be had over whether standards could be developed and distributed at lower cost of course.
There was a US senator in the early days of railroads who said something along the lines that wherever there was a change in railway gauge, a town appeared and commerce flourished. Just like Profibus.
If all you want is a discount on purchase of standards, books, or training, (that other people write) you can do the math and decide if it is worth it.
If you want to paticipate in the committees that write the standards and do other things for the industry you should join.
The problem with the ISA, profibus and everything else is it is tainted to the folks and companyies that are inside. The scary part is that these old engineers really think they know controls. They do, if all you want to do is fancy twist on PID.
They do not know shit about the software underlying products. The state-machine, kernel, executive, or RTOS is what makes or breaks a control system. The problem is embedded linux is leaving green-hills, allen bradley, Wind River and company behind in decades of old decrepted technology.
If you want to learn about real controls, you have to dig deeply into the underlying assemble and ansi-C code that runs on microprocessors, DSPs, and FPGAs. It is there you will really learn about controls, determinism, multi-threaded process etc etc. The PLC vendors push ancient controls systems build on pathetic state machines or RTOS, and the obstruficate the concepts of controls.
The SCADA vendors are even worse. The good news is now that the US government, NSA, cia, and fbi are looking closely at all of this expensive bullshit, they are realizing that only embedded linux can build secure control systems with modern functionaliity. Do not look for the vendors of these old-tired systems to make their software secure. They could not do it, if they tried. Time and again, I build devices and interfaces to 'sniff' out old-tired proprietary protocols that are mostly clear text. If they bother to use encryption, it's pathetically week.
I teach technician how to code in the assembler that is available on the controller, so they can understand the native assembler language and build modular programs that are portable. You can map the 'ladder logic' elements it block of assembly code. Once you do that, you can get all sorts of hardware to run controls systems on, make controls system distributed on top of RTlinux and purchase hardware anywhere.
At that point, you can use a real programming language like ansi-C. Don't get me wrong, if a company wants to pay me money to develop controls code a particular plc or scada system, then that's OK. However, when I show them code that runs on linux based pcs and the same code or it's assembler derivative on a demo board form a semiconductor manufacture (and orders of magnitude cheaper prices) they rarely choose the proprietary path.
Do look to the ISA or Profibus or devicenet(a real poor implementation of the CAN bus) or any of their associations to really teach you anything other than how to use their products and code to be a slave to their financial aspiriations.....
Dude, that's not engineering, that's what uneducated technician do...
Real engineers can code and solve problems in a variety of languages. My last major project involved writing ansi-C code to verify the logic and calculations of PLCs. I has to reorganize their thoughts to get the software happy for all of the 'regulators'. The really sad thing is I told them the solution was correct and operable, but not optimisitc. Now they want it optimized. I told them the only way to do that is with embedded linux. I offered hardware for free(only cost me less than a thousand bucks) all of the software free. They are still thinking about my offer.
The are senior members of the ISA......
Run, don't walk, to linux, ansi C and native assembler before you really think that ladder logic programming is robust.
PS Ladder logic is good for graphical representation, and simple tasks. It is not a robust solution for complex problems. If you really want tight control aka a high speed assembly line, you have to get into the guts of the RTOS running on the processor, to do things so that 'old_folks' say, 'how did you do that'.
A computer science degree never hurts..........EEs can not code for shit!
The problem with the ISA, profibus and everything else is it is tainted to the folks and companyies that are inside. The scary part is that these old engineers really think they know controls. They do, if all you want to do is fancy twist on PID.
They do not know shit about the software underlying products. The state-machine, kernel, executive, or RTOS is what makes or breaks a control system. The problem is embedded linux is leaving green-hills, allen bradley, Wind River and company behind in decades of old decrepted technology.
If you want to learn about real controls, you have to dig deeply into the underlying assemble and ansi-C code that runs on microprocessors, DSPs, and FPGAs. It is there you will really learn about controls, determinism, multi-threaded process etc etc. The PLC vendors push ancient controls systems build on pathetic state machines or RTOS, and the obstruficate the concepts of controls.
The SCADA vendors are even worse. The good news is now that the US government, NSA, cia, and fbi are looking closely at all of this expensive bullshit, they are realizing that only embedded linux can build secure control systems with modern functionaliity. Do not look for the vendors of these old-tired systems to make their software secure. They could not do it, if they tried. Time and again, I build devices and interfaces to 'sniff' out old-tired proprietary protocols that are mostly clear text. If they bother to use encryption, it's pathetically week.
I teach technician how to code in the assembler that is available on the controller, so they can understand the native assembler language and build modular programs that are portable. You can map the 'ladder logic' elements it block of assembly code. Once you do that, you can get all sorts of hardware to run controls systems on, make controls system distributed on top of RTlinux and purchase hardware anywhere.
At that point, you can use a real programming language like ansi-C. Don't get me wrong, if a company wants to pay me money to develop controls code a particular plc or scada system, then that's OK. However, when I show them code that runs on linux based pcs and the same code or it's assembler derivative on a demo board form a semiconductor manufacture (and orders of magnitude cheaper prices) they rarely choose the proprietary path.
Do look to the ISA or Profibus or devicenet(a real poor implementation of the CAN bus) or any of their associations to really teach you anything other than how to use their products and code to be a slave to their financial aspiriations.....
Dude, that's not engineering, that's what uneducated technician do...
Real engineers can code and solve problems in a variety of languages. My last major project involved writing ansi-C code to verify the logic and calculations of PLCs. I has to reorganize their thoughts to get the software happy for all of the 'regulators'. The really sad thing is I told them the solution was correct and operable, but not optimisitc. Now they want it optimized. I told them the only way to do that is with embedded linux. I offered hardware for free(only cost me less than a thousand bucks) all of the software free. They are still thinking about my offer.
The are senior members of the ISA......
Run, don't walk, to linux, ansi C and native assembler before you really think that ladder logic programming is robust.
PS Ladder logic is good for graphical representation, and simple tasks. It is not a robust solution for complex problems. If you really want tight control aka a high speed assembly line, you have to get into the guts of the RTOS running on the processor, to do things so that 'old_folks' say, 'how did you do that'.
A computer science degree never hurts..........EEs can not code for shit!
Let me repeat this little story a professor at Purdue told us in a controls class back some time ago--seems a government commissioned at study, I think it was in Russia, to look at industry and determine how much benefit could be obtained by applying modern control methods. Sorry but the details have faded a bit in my memory. Anyway, the study reported out that about 99% of the control processes they examined were at or near optimal using PID controllers. Seems those old boys in the plants, while not really understanding everying that was happening, managed over time to tweek the controls to about as good as was possible. I think the point of the story was as we study modern control we should retain a bit of humility, because all that neat stuff we learn is only required 1% of the time.
Those Russians must have done well, or they are lying through their teeth, but they have a point. From what I can tell, a large portion of controls are either poorly tuned, or, in many cases poorly constructed. It isn't that PID won't work well. It is that PID isn't being used as well as it can be. Of course, they may not have looked closely enough at the systems being controlled, and may have a different viewpoint of "optimized". If they are talking about just controlling a simple flow rate with a valve, then that is one thing. PID does not do whole plant optimization.
OK, I'd agree with both points, most controls are simple and most can be performed adequatedly with stochastic and empiracle methods. So why pay Allen-Bradley, Modicon, or other proprietary controls vendors, like those promoted by the ISA, thousands of dollars for circuits and microcontrollers, that you can purchase less than $99 dollars per board, off the shelf? Why used crippled, deficient, security proned software from vendors that build software development programming environments from crippled vendors such as microsoft? The same rings true for SCADA packages, when you can use linux, and get security enhancements, that work?
If 2 engineers build controls systems that perform adequately, but one costs orders of magnitude more, which one would you deploy? You cannot get inside of the software or the microcontroller to see what's actually going on (microcontrollers have wonderful standard interfaces called JTAG, you should learn about JTAG if want to be useful in the future) and deal with a myriad of issues including but not limited to security problems?
Which engineer would you hire? Which engineer makes more profit? Which engineer can actually secure the critical controls infrastructure in the US?
Get real.....Get educated, and for god's sake dump microsoft, allen-bradely, modicon, etc etc, and go back to being a real engineeer.... Use circuits designs that work, and software that you write. Who knows, you may actually enjoy being a real engineer, instead of pimping for the ISA and the other vendors, that do not give a damn about the average working engineer....
Well, I can give a couple reasons. I want to make sure that the system I buy today is going to composed of readily available parts, that those parts are designed properly, that the machine interfaces work in a very standard method, and that there is a user interface that doesn't look like an afterthought. I want a uniform ladder logic system, a good alarm system, a great data historian, and the ability to have my systems communicate with one another easily. I also want an organization to stand behind their product with an unlimited liability agreement. For giggles, I also want to know that whatever I buy today will be superseded with a better, more capable system in the not too distant future.
Sure, I can come up with engineers who like to play with microprocessors and such. I can even find a few good ones. What I typically would need, however, is someone who understands the system dynamics of a large scale chemical process, and knows which units to put where in order to get the best control possible. If these companies have already adequately invented the wheel, then it saves me the trouble of doing it.
I don't want someone to cobble together a system of $99 boards and a bunch of PC's. I've dealt with those boards and those systems. It is at best a crap shoot as to whether that comes our right. With a good engineer, it works great, at least the parts he's good at and while he's around. With two good engineers, I can end up with a maintenance nightmare. With a poor engineer I'd be better off with manual valves.
As far as which engineer I'd employ, I'll look at the long term economics. If I have to have low level programming done with each and every loop, I'd quickly find that the cheaper hardware takes longer to install, test, and verify. I'd also find that making sure I can get the right parts if it breaks gets expensive in a couple years. I'd have to constantly worry that whatever code was written was indeed correct. I'd also have to make sure that the code was well backed up and that I have a staff who can work on it. The expensive engineer who called a vendor, ordered a dozen of this, and a dozen of that, knowing that each will fit together and perform properly on the process, and inside of a few weeks or months has the whole thing running starts to look very good.
Personally, I don't care if the system uses MS or a proprietary system. It has to work, completely, and quickly.
This "old engineer" has learned that accuracy in detail is of utmost importance in any control system whether it be relay based or high-tech. The misplacement of a single wire in relays, a single comma in code, or a single bit in a packet invalidates the entire system. That is why I am extremely suspicious of any code writer, programmer, etc. whose written work is full of spelling mistakes and other sloppiness.
"If you want to learn about real controls, you have to dig deeply into the underlying assemble and ansi-C code that runs on microprocessors, DSPs, and FPGAs. It is there you will really learn about controls, ..." Actually, no. What you learn there is about programming. If you want to learn about controls, you did deeply into Piping and Instrument Diagrams, and the behaviour of process equipment, the requirements of operators and their interface, and the various codes governing safety and reliability. The rest is details.
"I told them the solution was correct and operable, but not optimisitc..." Does that make the solution pessimistic? Now I know that many details are important, but I have never before been concerned with the emotional state of a program.
I have seen a few plants that were controlled by $99 board cobbled together. They may have worked for a while, but soon the plant was mess. Pretty soon these on-the-cheap systems were replaced by real control systems, using DCSs and PLCs, supplied by companies that had been in the business for years and will continue to be around. Most plants expect a control system to work for years without interruption, to be expandable and upgradable while still operating the plant, and for the vendor to have knowledgable applications engineers who have experience in the industry.
I have never seen a control system not function because the programmer didn't get involved in the low level software or used the wrong operating sytem. I have seen many systems not operate properly because the control engineers did not have sufficient knowledge of the process and of basic process control, or who did not fully understand the needs of the operators.
The most successful control engineers (measured by results in good plant operations, were chemical engineers or others with appropriate knowledge and experience in their industry, including experience that went far afield of just process control and included process design and operations. Knowledge of programming may allow you to make some elegant looking code, but it isn't enough to allow you to make a process plant run efficiently and safely.
Hm, PLC vendors pay semiconductor companies less that $10 for the chips. For persons that do not want to design an actual circuit board to test something, or deploy a product rapidly, you can often purchase modules or development boards. The is not low quality about this, as Allen Bradley, Automation Direct, Seimens (who is actually a semiconductor company too) etc etc use this approach. You'd be suprised at what they wrap inside of a nice enclosure, and add 3 orders of magnitude to the price, and sell to chumps you the best of the ISA.....
It's your money, or the lack thereof. If you follow the dribblings of the ISA, you'd think the controls industry is in recession. No, it is not, it booming, just not with the deployment of overly expensive big name vendors. The DOD and many other groups are droping COTS control equipment, primarily for security reasons, but also for costs. And new paradigms that encompasse traditional approaches to controls and have many new features, are displaysing these antequated technologies. That's why the ISA is gloom and doom, and guys lke myself consult directly at excellent consulting rate, and you guys are continuing the misery of traditional ( and currently unemployed) controls engineers.
You know what, why don't you attend a semiconductor conference and tell TI their equipment sucks? Or pick another semiconductor company, like Motorola, that has been building their own control systems for decade and have left the product and it's expensive prices to keep racking in thousands of dollars when a $30 and a real engineer would do?
Um your statements are self_incrmiminating of your personal skill set.
Hey, now you are showing original thought. I typically fix stuff behind vendors and ladder logic guys, because I can look deeply into a problem.
Let's take sampling rate as an example. If you have a problem and you bring in data, via a plc, how fast (how often) can use sample? What happens when you find a problem that the vendors best PLC does carry the necessary number of bits, at a fast enough sample rate?
Duuhhhhhhhhh, didn't know that such problems existed...........
WE'll learn about DSPS and sampling rates on analog sensor technology and you can begin to see how traditional plc vendors are ok for normal problems (although their solution is expensive) and fail to grasp or work at all in complex situations.
Hey, the price one pays for materials does not reflect on the quality of work. Allen Bradley et all purchase material for a far lower price than I can. But the look of their work is top notch, but, expensive when you see it. Just because you pay a low price for something does not mean that the installation work has to look poor. And It's the same microprocessors and electronics the big boys use, minus the price.
your conclusions are illogical and non-sequitor...
Obviously you have lead a sheltered life....
Yes these are prerequisites we all assume of each other I could cheaply say these things about others, but, these issue are irrespective of the underlying technology, which, is what I thought the discussion should focus on. I'm assuming you guys are competent engineers. Most definately I am, PE et al.
Dude, you finally said something I agree with. I do indeed have a petrochemical degree, and EE degree and a masters is computer science and a PE to boot (yes I passed the piss-ant of test concocted by the ISA, in less than 2 hours for an 8 hour test. (you know first to leave kind of guy, in a room full of 800 wannabees.......) PE or a other degrees do not mean anything. My field experiences, and my time DESIGNING solutions and not perveying solutions that other came up with, are what matters and works best.
The $99 board may have a better, faster chip of equal quality, however it is probably missing all the packaging, EMI protection and other items surrounding the chip that make it reliable in an industrial environment. This stuff *does* matter, and the more of it you have around, and the longer you expect it to work, and the higher the costs of problems, the more it matters.
Dude, it's email on a discussion group. I use all sorts of ethnic and illiterate gestures, often to make a point. If thought a spell check was necessary, I'd configure it to run automatcially. In this forum it ain't, so get over yourself and your condecending ways..........
I'm not asking you for work, I have plenty and I'm designing new products....
Wrong! yes programming is a necessary tool, and if you are going to write ladder logic programs, you'd be doing yourself a hugh favor and learn to code in several other languages, including assembler and ansi C.
The underlying RTOS defines how your PLC code will run and operate. If you are only closing a valve that has to take at least 5 seconds, but, no more than 8, for process or water hammer considerations, then ladder logic is OK.
If you are controling the guidance system on something that has complex delivery and travels in excess of mach4, then the underlying timing, provided by the RTOS, is critical. You cannot leave this to VXworks (er I mean allen bradely).
You know, I assumed we were all going to be charatible and consider that each other had mastered the traditional craft of controls. If someone indicates they need help, or are deficient, then you'd have a valid point. Dude, I'm what they call 'elite'. I assume the good ole boys (and many of my friends are indeed good ole boys) are damn good at what they do. Elite is more like magical. I do things that other controls engineers say, "how'd you do that?" As long as we stay polite and friendly, I do not mind showing folks a better way, if they ask.
Dude optimistic is a mathematical term. There is not place here for childish emotion. I just assumed this of everyone?
Pessimistic equated to outright failure or a filter that denys most things, in a mathematical sense. I hope we're not exploring the realm of human emotions, if we are, count me out of here!
PS, If you are ever so lucky to have me on your payroll, then you can bitch about spelling and grammer. At that point, I'll spend the extra energy on a
pretty format (dude this is a programming term not an emotional schism)
Now here we go again taking things out of context. If you assume that Analog IOfrom a major vendor, for example, is better that Analog IO uniquely implemented you may be right or wrong. Most boards from vendors such as Allen Bradley, Siemens etc, use common grounds. I often use a seperate grounding systems for Analog IO for higher accuracy needs. Vendors of systems make many, many economic trade offs that you are un aware of or incorrectly make assumptions about. I DESIGN what it needed, so don't assume that just because I spend $99 for something you pay thousands of dollars for, that my system is inferior......
I'm currently design a datalogger for a niche market. Surge protection is a big concern as most the 'big name vendors' in this space have problems with surge. I have test about 15 of the best modules made, and selected the one that performs the best. It happens to be on of the most expensive surge protection module anywhere for this interface.....
Please do not assume my work is inadequate. My work is elite, and 99% of my business is from broken or disfunctional situations where folks have already spend rediculous sums of money. Parts and materials are cheap. Really good engineering is a lost art, especially here in the States... Excellent engineering may or may not use commercial big-name vendor materials. It all depends on what you are familiar with and if you want to save money, or be proud of a expensive big-vendor name. It's your call, and your employeer's bottom line. Don't bitch one day when you wake up, and your employeers has hired a bunch of kinds from a foreign country, because they'll be most likely to use embedded linux, and save their employer lots of cash on material your payroll....
But it's fun jerking their chains. Actually, it's an experiment: I'm trying to guess what kind of fool he is. I've met this type before. He believes he is a super genius and that everybody else is an idiot.
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