You're asking an awful lot from a guy who's repeatedly praised the solution he's already got. You're the one who sounds like he thinks the industry has their collective head up their collective ass, and I was issuing you a challenge, to put your money where your mouth is. Don't try and turn it around on me.

Point is, if you really believe in all this crap you're spouting, then from your point of view, this should appear as the opportunity of a lifetime, with a red carpet rolled out just for you. You're the only one who hears the market silently crying out for this new solution that it doesn't yet know that it needs. Go out there and answer the call. Take the opportunity and boldly go where no man has gone before. I don't know why you aren't doing it yet. Why are you on this forum wasting time, filling the internet with your brilliant ideas? Why are you giving away these golden nuggets?

Why not? Because not even you believes what you are saying. I theorize that it's part of the canned social/political ideal package you subscribe to, to hate PLC manufacturers because they make the big bucks. That whole 1% and 99% thing. They're evil because they're greedy, capitalist pigs. Well, whatever. To each his own. I don't have time for this discussion anymore. I have opportunities to follow up on. Good talking with you.

P.S. If you do invest in your ideas and you do make some kind of device, let me know, I might be interested. If you make that exact device I described, I really will buy it for $200/pop.

Good on you. Personally, I'd pass. I need a much stronger show of reliability. Support is one thing. Up time is another.

 

Good on you. Personally, I'd pass. I need a much stronger show of reliability. Support is one thing. Up time is another.

I'd put it through my own torture test. If it can operate inside a pressurized steam box bouncing around in the back of my truck for a couple of weeks as i drive around town, then it should be alright.

And if it did survive, well that would be one hell of a handy thing to have. A $200 micro brick PLC with analog I/O, complex instruction set, and floating point? Come on, that's the holy grail.

 

I don't hate big PLCs companies. There's no need to put words into my mouse. I have my own.

I have said that PLCs don't have any technical merits - big, inefficient, clumsy, and expensive. You failed to name any technical benefits. Instead, you only explained how PLCs help you get extra $100 from your clients. I completely agree that PLCs are well fit to your business model. That was my point all along - PLCs are not an object of technical excellence, but a method to extract money from clients (read my first post). You brilliantly confirmed it. Thanks for playing along.

 

You failed to name any technical benefits. Instead, you only explained how PLCs help you get extra $100 from your clients.

Post #7, go read it again, again.

 

I don't hate big PLCs companies. There's no need to put words into my mouse. I have my own.

I have said that PLCs don't have any technical merits - big, inefficient, clumsy, and expensive. You failed to name any technical benefits. Instead, you only explained how PLCs help you get extra $100 from your clients. I completely agree that PLCs are well fit to your business model. That was my point all along - PLCs are not an object of technical excellence, but a method to extract money from clients (read my first post). You brilliantly confirmed it. Thanks for playing along.

Another engineer making market predictions?, just don't look to the past cause it proves you wrong. What do you have then to offer solutions in the future, cause I'm looking to invest in the future.

 

Post #7, go read it again, again.

Do you think if I read it again it becomes better?

 

Or are you just frustrated because you can't afford compliance.

 

This is a long thread, and I don't have time to read the whole thing. Another factor in the purchasing decision is the plant supervisor, and the plant electrician who are responsible for installation and maintenance. They grew up learning ladder logic for relay systems. A PLC preserves that programming paradigm and they love it. You can try selling new ideas to that conservative crowd, but NOBODY EVER GOT FIRED FOR BUYING ALLEN-BRADLEY. So that is what you are up against. My money is on the PLC folks, but yer more 'n welcome to crack your nut on this one.

 

Or are you just frustrated because you can't afford compliance.

Yeah, why didn't I think of that? That makes way more sense than my theory. He's probably been there, done that, had his dreams crushed by the reality of compliance cost, and the experience stripped him of everything but bitterness. If that's the case then I totally understand his grudge against PLCs.

 

I came into this also thinking that PLCs didn't make much sense over MCU's. However, I've changed my mind. This is my understanding why.

People use PLCs over MCUs the same reason people will use an Arduino and shields over a bare ATMEL MCU and peripherals. The Arduino development platform is more convenient, flexible, and allows rapid development. They may cost more, but it's worth it in the right setting. You COULD use the bare MCU, and integrate only what you needed for your application, and save money. However, it's still not worth doing if time is highly valuable, like it is in industry.

Also, although I've never programmed a PLC, I'm under the impression that PLC software allows multiple engineers to create time-sensitive programs without "stepping on each others shoes". It might be more restrictive overall, but it's not really a problem, and yet it satisfies a must-have requirement. That is, the requirement to be super easy to develop on, to get stuff done ASAP.

If you tried designing a box that had all the benefits of a PLC, but with a MCU, you'd end up exactly where the other PLC manufacturers are. A MCU with an "expensive box around it". A PLC.

Are PLCs elegant? Perhaps not, but they conform to the needs of the real world. Not the other way around.

I found a good explanation on wikipedia: https://en.wikipedia.org/wiki/Programmable_logic_controller#PLC_compared_with_other_control_systems

Specifically, this section:
"PLCs are well adapted to a range of automation tasks. These are typically industrial processes in manufacturing where the cost of developing and maintaining the automation system is high relative to the total cost of the automation, and where changes to the system would be expected during its operational life. PLCs contain input and output devices compatible with industrial pilot devices and controls; little electrical design is required, and the design problem centers on expressing the desired sequence of operations. PLC applications are typically highly customized systems, so the cost of a packaged PLC is low compared to the cost of a specific custom-built controller design. On the other hand, in the case of mass-produced goods, customized control systems are economical. This is due to the lower cost of the components, which can be optimally chosen instead of a "generic" solution, and where the non-recurring engineering charges are spread over thousands or millions of units."

and

"A microcontroller-based design would be appropriate where hundreds or thousands of units will be produced and so the development cost (design of power supplies, input/output hardware, and necessary testing and certification) can be spread over many sales, and where the end-user would not need to alter the control. Automotive applications are an example; millions of units are built each year, and very few end-users alter the programming of these controllers. However, some specialty vehicles such as transit buses economically use PLCs instead of custom-designed controls, because the volumes are low and the development cost would be uneconomical."