Do you guys think one could compete in the PLC market?  - Page 1
Forum section: electronics / general

author: rwgast_lowlevellogicdesin
author_rank: Frequent Contributor
timestamp: October 18, 2015, 03:46:02 pm
content: So recently I have been looking for jobs getting a skills based resume togather to try to get a job in electronics. Ive spent my career as a Unioun sparky but I have never programmed a PLC that is someone elses job. Some of the jobs I am fully qualified for require PLC experience. I am going to download a TRI Log PLC sim since it is free and uses ladder logic and Basic. Hopefully I can teach myself ladder logic in a daywell see, cant be anywhere as hard as using C with no libraries or ASM. If anyone knows of a better more relevant sim I would love to hear about it, as long as it is free.Ive mentioned I am interested in making test equipment and bootstrapping myself on Tindie. While some say this will never amount to a living Dave chimed in on his uCurrent and said it is possible to make modest means of one kit, although he has a WIDE audience to market too, I have seen some Tindie sellers doing very well if there following the 2.5x rule on there bomb.I had talked to some people on another forum about some ideas, one person had brought up a PLC. Since I would be using an 100mhz 8 core propeller it would be a unique idea. The idea is the average PLC is quick enough for most automation. But the propeller chip is totally deterministic and somewhat a software defined FPGA (in other peoples words, not flame bait lol). This means you can accurately control loop times, each chip also has 16 counters... so thinks get pretty interesting. If I did this my idea would to be to link two together over a spi bus or a 1Mbit Uart and add a few SPI Srams and other unintresting things like a RTC etc...But one thing I see is most PLC's just use relays on the ouputs.... my idea would be something more like each cog (or core to the non parallaxian) could be attached to an I/O. This means each I/O would have two counter objects and could quickly and deterministicly control each input output, along with having access to two timers. On outputs It seems that giving the user a choice between a standard solid state relay and a triac would be a good idea, or a third option of an adjustable 1-24vDC output using a fet.I would probably desingn the hardware and firmware, and than build a cross platform utility to convert ladder logic to PropASM. As far as the PC programming interface goes I would most likely find someone out there that can write a nice looking gui program that is cross platform! I also think adding ethernet and/or a cheap wifi setup like a wiznet or wifi router type would be a good idea so the PLC could be remotely programmed.Now I know siemens and allan bradely run this market.... but I honestly think I could get more done in a smaller form factor and hopefully for less money. This is the kind of project I would prototype most of first, the go to an incubator or kickstarter. Simply because the reality behind this is without UL and CE it would never be adopted beyond hobbyist....So am I trying to battle google or could this be possible as far as making something competitive? Also what would any PLC users out there like to see that may make it more competitive?

author: nctnico
author_rank: Super Contributor
timestamp: October 18, 2015, 07:18:13 pm
content: You'd also need to implement a field bus interface like Profibus.I'm not quite sure speed is a problem in current PLCs. You can throw a lot at a Siemens PLC before it runs out of time. Getting to ms timing resolution isn't a problem. Where I do see problems is that interfacing with serial port protocols is more difficult (serial ports for a PLC are insanely expensive BTW), doing something with data is not easy and memory is quite limited. Even with the higher end Siemens PLCs you have to plan carefully if you want to store a few kB of data to do processing on. What could be a defining feature is to be able to use a procedural language like Lua (easy to learn) in a PLC to provide support for serial protocols and do calculations on data. This way you can make self contained systems without needing to offload certain functions to a PC.

author: hendorog
author_rank: Super Contributor
timestamp: October 18, 2015, 07:55:29 pm
content: I've been out of the PLC game for over 10 years so take this with a grain of salt.Based on what you have said I would think you will pick up PLC programming very easily. Your practical experience as a sparky will pay dividends big time.Developing a PLC isn't worth it I'd suggest. Its been done to death and cheap off brand PLC's are available too.Also, for most jobs the hardware is specified and is brand name stuff, so the flexibility to use something else isn't there.However there were (and maybe still are?) opportunities do develop relatively simple modules when the off the shelf stuff is too expensive, or not available, for a particular application.I always felt that a low cost combination of an embedded linux PC for flexibility and comms, and a PLC for determinism and I/O would be very handy.I did a lot of serial interfacing work. In the PLC rack a module was needed, and was programmed in BASIC, but the CPU and interpreter were so slow that I found assembler was often required to get the performance. I expect that has improved now though.

author: rwgast_lowlevellogicdesin
author_rank: Frequent Contributor
timestamp: October 18, 2015, 07:59:41 pm
content: Hmmm I thought being able to get accurate deterministic timing to the pico second would be a cool feature... I cant remmber there names but there are PLCs based on the ATMega chips which allow programming threw the Arduino IDE. One of them was CE and UL in a nice little tuff looking plc enclosure and it also broke all the micros pins out. I was under the impression that if you wanted wide adoption you had to basically at least be able to run ladder logic, because that's what people know well.My idea for programming would be to just upload the code remotely or via USB. As far as storage goes I figured some SRAM chips, and an SD card. The SRAM would act as a buffer between the SD card basically. Heck maybe even allow the PLC to read a compiled code file from the SD too.Ah hah here it ishttp://controllino.cc/Is this basically what you think a better PLC is? Im just under the assumption ladder logic is pretty much a must, I wouldnt mind supporting some scripting too but why hasnt that little guy i linked too taken over Siemens and Allen Bradley? I was thinking becuase a tech doesnt wanna invest time to learn a real programming language? I mean the box is UL and CE so what issues do you see with it?

author: LabSpokane
author_rank: Super Contributor
timestamp: October 18, 2015, 08:12:43 pm
content: What industrial process needs ps timing? Anything that does that will have its own CPU built-in and do all of that locally then communicate back on a fill-in-the-bus network.The PLC market is pretty well saturated. if you have a unique transducer solution, then that would be a better entry point.

author: hendorog
author_rank: Super Contributor
timestamp: October 18, 2015, 08:33:36 pm
content: Quote from: rwgast_lowlevellogicdesin on October 18, 2015, 07:59:41 pmFirstly because its not spec'd in contracts. The industry is reasonably traditional so it's hard to win a contract with a PLC noone has heard of.Second because the range is limited to tiny PLC's only - their 'Mega' is a really small PLCThird because its not really super cheap so probably doesn't offer much over the name brand low end stuff. Also companies that use a lot of PLC's get big discounts.Fourth because they don't have any distribution network. Even here in Auckland we had local Omron, Rockwell/AB, Schneider/Modicon, and Siemens agents. Plus there was someone pushing an oddball Fisher & Paykel in house developed PLC and a National Instruments place.

author: hans
author_rank: Super Contributor
timestamp: October 18, 2015, 08:53:40 pm
content: I don't think using a novel CPU architecture in a PLC will make it revolutionary.PLC's are built in big installations where you want high reliable and proven electronics. You could say it's a ripoff for the functional hardware you get, but maybe it's not after all validation that has been done on that hardware (like; will it survive 48V on a 12V input? Or 48V on analog 0-5V input? Or maybe -12V on inputs? What happens to the outputs when the PLC starts up? What can you do when the power goes down? What happens if there is a firmware bug in the PLC middleware? etc.).The big name brands have that reputation, I presume, and have tools that are familiar to people working in the field. You don't want an installation to go bad 2 years later because you could have saved a few hundred $ on the PLC during purchase, while the factory goes down for hours or days (costs a lot more ultimately) and the engineer that designed the installation is not around anymore.All PLC vacancies I see around in my area specify programming experience required in C++ or STL.

author: LabSpokane
author_rank: Super Contributor
timestamp: October 18, 2015, 10:14:39 pm
content: For the systems that I work with, the PLC(s) is/are approximately 0.5% of the overall system price and maybe 0.1% of the total plant cost. That's using Allen Bradley. Include all the panels, instruments, etc. and it's maybe 1.5% at most. The only exception to this is when one is forced to use a safety-rated PLC, then we're talking major money. But, those have a lot of design, test, and certification costs, so that's what drives the price.I just don't see this void in the PLC market that must be filled. The low end is covered with Automation Direct, Keyence, et. al. The high end is covered. For anything outside of the US, it is almost always a Siemens PLC that is specified. And really, for a large plant, that PLC is becoming a DCS unless a PLC is required as a dedicated system for a safety-rated application.So, in other words, Allen Bradley, Siemens, et. al. will continue to be able to charge tens of thousands for a PLC and get it, because the cost of the device is insignificant compared to the trouble that a poorly-designed device could cause. The likelihood that a new competitor will take over the market based on price or CPU speed is essentially zero. No one with industry experience would take so much risk, so save so little.

author: nctnico
author_rank: Super Contributor
timestamp: October 18, 2015, 10:53:05 pm
content: Quote from: LabSpokane on October 18, 2015, 10:14:39 pmI wouldn't be so sure about that. I have some customers who use PLCs in their standard mechatronic products. $100 saved on each PLC adds up to quite a large sum of money quickly. Really big & expensive plants are few in number. It is the standard products where the market is for price competitive businesses. With an increasing wish for connectivity & remote access/diagnostics there certainly is a competitive USP for a new company on the market.

author: briselec
author_rank: Regular Contributor
timestamp: October 19, 2015, 12:28:36 am
content: For starters if you're looking at the standard listed price of PLCs and think you can compete against that then you are very wrong. That's only what the one off buyers pay. OEMs are probably paying only a third of that. It's been a while since I worked in the OEM field but from memory 63% discount was fairly common.PLCs do not just use relays. Output modules come in different versions. It's up to the guy building the system as to which one suits.As far as cheap, small form factor - it's already out there.The big thing the industry has been crying out for for years is a common open source software suite that works on all makes of PLC equipment. It's a real pain in the neck needing a different software suite for every make of PLC in a factory. But that's a massive, massive project. Some guy called Dave tried to make it happen many years ago but he didn't get far with it.

author: CustomEngineerer
author_rank: Frequent Contributor
timestamp: October 24, 2015, 07:18:32 am
content: Quote from: briselec on October 19, 2015, 12:28:36 amWho is this guy called Dave of which you speak? He sounds interesting and I wish to subscribe to his newsletter.

author: EEVblog
author_rank: Unknown
timestamp: October 24, 2015, 09:05:40 am
content: Off the bat I'd say don't bother trying to crack the PLC market.From a user standpoint (at least when I worked with PLC's) trust in brand name was everything. People who design and build PLC based systems stick with the brand they know, and there is always big money available to buy those brand names. Few are going to risk using an unknown start-up brand PLC when it's their arse on the line if it proves unreliable etc.Kind of like the alarm industry. No installer worth their salt is going to install a no-name brand alarm system. They stick with the ones that have been proven over decades.

author: Jeroen3
author_rank: Super Contributor
timestamp: October 24, 2015, 10:56:30 am
content: The alarm industry is a bit corrupted due to insurance companies not accepting, or heavily increasing the price, with the cheap brands. Not really a fair comparison.But it is indeed true that people who look into the future further away than 1 quarter, will often choose the solution they are most confident with that it will not require warranty work.

author: EEVblog
author_rank: Unknown
timestamp: October 24, 2015, 11:30:39 am
content: Quote from: Jeroen3 on October 24, 2015, 10:56:30 amIt's also the same reason why when I was developing and building production test jigs, I'd buy expensive National Instruments gear and Agilent/Tek/Fluke gear. They all just worked and are industry proven. I wasn't going to dick around with cheap products that could delay things and make me look like a goose because Murphy got me.Same reason why you often design in expensive $50 DC-DC converter modules into a design instead of rolling your on with $5 worth of parts if you can get away with it. Because it's not worth the potential risk/hassle/time.

author: han
author_rank: Frequent Contributor
timestamp: October 24, 2015, 12:01:46 pm
content: Maybe Zelio Smart Relay not PLC, but quite close.It's have ATMEGA 128 insideBasically PLC is micro controller with protection/isolation between input and output..But to fight again big brand is not easy, they have lot of ahead bug less(not bug free), reliability, ....IMHO, From stand point third world country anything form USA is a quality one, so you have advantage in location,the rest is good product and marketing.

author: B.B.Bubby
author_rank: Regular Contributor
timestamp: October 30, 2015, 11:11:47 am
content: A good, cheap PLC that can be programed in Basic / structured text would the go for sure. I've used some of the cheap programmable relays and writing control logic with function blocks and ladder logic just suck, big time suck!!!Ladder logic needs to be forgotten, wiped from the face of the earth, christ even "C" is better.Focus on the ide / software side - the hardware is the easy bit.

author: forrestc
author_rank: Unknown
timestamp: October 30, 2015, 11:29:49 am
content: Before you go down the build your own path, you should really look athttp://www.automationdirect.com/adc/Shopping/Catalog/Programmable_Controllers. Pay close attention to all of the modules, varieties and functions available.Then look athttp://www.industrialshields.com/en/home?gclid=CN2Mwd2J6sgCFUmUfgodWJMNGgThen follow up with the following Google searches:arduino plcopen source plcopen source ladder logickickstarter plcOh and this website:http://cq.cx/ladder.plAnd this website:http://evotronics.eu/en/picoplcI could go on and on and on.This is a *very dense* marketplace. If you can find a niche that isn't well done, then you can probably do well. But there is so much stuff out there, you'll need to spend a lot of time just learning what exists.This is *NOT* intended to discourage you, just warning you about how much stuff is already out there, and the fact that almost everything you described you can get off the shelf today.

author: briselec
author_rank: Regular Contributor
timestamp: November 01, 2015, 08:44:16 am
content: Quote from: B.B.Bubby on October 30, 2015, 11:11:47 amPLCs are used in industrial installations where you want a basic industrial electrician who has never used a HLL in his life to be able to tell why a system isn't working correctly. Ladder Logic serves that purpose very well.I suspect you found it sucked because of the way it was implemented by the maker of the cheap programmable relay, not because it was ladder logic. If you ever get the chance, try Omron gear. I've found their stuff to be the most intuitive and easy to use.

author: nctnico
author_rank: Super Contributor
timestamp: November 01, 2015, 01:56:27 pm
content: Quote from: briselec on November 01, 2015, 08:44:16 amDon't get your hopes up. Sparkies which are competent enough to work on such systems are rare (and are becoming rarer) so having ladder logic to program a PLC makes less and less sense.

author: briselec
author_rank: Regular Contributor
timestamp: November 01, 2015, 09:02:39 pm
content: Quote from: nctnico on November 01, 2015, 01:56:27 pmReally? Yoohoo! Time for a pay rise

author: CM800
author_rank: Frequent Contributor
timestamp: November 01, 2015, 11:12:33 pm
content: In my personal opinion, coming from the motion control sector. Bringing a product into the systems area of the market is a bad idea right now, it is a very difficult area to get into for reasons highlighted above (brand name products, traditional methods, etc.)The only areas I would hope to push towards getting into are OEM products, e.g. controllers, servo drives etc. for 50-100pa machines that companies sell, such as dispensing machines, packing machines and more generic automated equipment.These areas are much easier to get into (it's part of what the company I work for does) and once you have your foot through the door with many companies, it is much easier to pass on future products to them to help re-enforce your market presence. Once you can claim a decent amount sold or the interest of some big names, other companies will become more interested in your products as well.Your best chance is looking at someone's machine at a company and saying 'our product can do that better for you, for less, it will allow you to move product through x times faster and save you potentially x much money, it is also very easy to integrate into your existing solution and setup time will be minimal (or we will even do it for you)Don't make a product looking for a problem, find someone's problem and make a solution for it, then sell it to them, find other people with that problem and sell it to them as well.Just my 2 pence.