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Arduino unveils the Opta – “Micro PLC” for industrial IoT

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Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#71

Post by tda »

dfox wrote: post #61
DannyBee wrote: post #3

I do a lot of PLC work. The Arduino IDE is totally unsuitable for it. No idea what they are doing about this. It would take an amazing amount of work to fix this. As for PLC functionality people actually use, the product page says "Optional support for standard IEC 61131-3 PLC languages". This is what folks use for real. I presume this means "we didn't want to pay CodeSys but you can". Or something. That sucks. Maybe…

My experience from integrating various automation systems (typically large-ish roller conveyor systems) is that often IEC 61131 languages are actually detrimental to productivity of the PLC programmers. It is this weird turing tarpit where anything that can be expressed as ladder logic is simple and point an click (modulo the horrible UI/UX of every single PLC IDE) but anything more complex than that is huge pain bec…

I just got my feet wet with an s7-1200 and I could not have imagined how horrible the programming of a PLC is. I spent a day just to get the plc send out UDP packets at 25Hz.

Apparently going above 10Hz is not really supported so you have to do silly tricks. I ended up running the send command on every tick, and running a time triggered cycle that toggles a bit at 50Hz and then using the rising edge of that bit to actually start the secretly async task of sending 20 bytes on the wire.

Son far I have learnt that async tasks are hidden, memory is measured in Kb, there is no guarantee for cycle time whatsoever, the programming model is really awkward, lots of config cannot be stored as code, version control is a bolted on nightmare, etc, etc.

Really makes me wonder what a PLC can do that an arduino/esp32/rp2040 can not. I'm really struggling to see the value other than that the hardware is reliable and "industrial".

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#72

Post by dfox »

tda wrote: post #71
dfox wrote: post #61

Earlier quoted context omitted.

My experience from integrating various automation systems (typically large-ish roller conveyor systems) is that often IEC 61131 languages are actually detrimental to productivity of the PLC programmers. It is this weird turing tarpit where anything that can be expressed as ladder logic is simple and point an click (modulo the horrible UI/UX of every single PLC IDE) but anything more complex than that is huge pain bec…

I just got my feet wet with an s7-1200 and I could not have imagined how horrible the programming of a PLC is. I spent a day just to get the plc send out UDP packets at 25Hz. Apparently going above 10Hz is not really supported so you have to do silly tricks. I ended up running the send command on every tick, and running a time triggered cycle that toggles a bit at 50Hz and then using the rising edge of that bit to ac…

In industrial automation you are not supposed to do anything at 50Hz, the reasoning is simple: more times than not you are simply turning on and off something that is AC powered and you do that probably with mechanical relays and contactors, quite obviously it is pointless to do that faster than some multiple of AC line period. It is simply about trusting the supplier, certifications and perceived reliability of the thing.

On the other hand even brand name PLC hardware is not that expensive if you factor in the fact that interfacing with 24V and mains-level logic is somewhat complex engineering problem. Relays and optocouplers are expensive.

Edit: and as for what PLCs can do that random MCU cannot: the Chinese Mitsubishi GX/FX clones mentioned in the sibling thread are essentially STM32 eval boards with industrial I/O and preloaded PLC firmware, nothing more, nothing less, so there you go.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#73

Post by FeistySkink »

scoutt wrote: post #41
colordrops wrote: post #36

Earlier quoted context omitted.

> one coworker, in interviews with candidates, always leaves the room as soon as the candidate mentions Arduino Sounds like these candidates dodged a bullet.

She is the sweetest person in the world, and always come back like after 5 seconds. It's a joke :)

Damn, two red flags in the span of 5 seconds.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#74

Post by wrycoder »

vvanders wrote: post #69
HeyLaughingBoy wrote: post #45

Earlier quoted context omitted.

> I can see that things like these would be a good step up for those who were originally not even using PLCs I agree that that's what Arduino thinks the market is, but I disagree that their conceptual market will buy this. Arduino-branded hardware is typically 5x the cost of the clones (remember, it's OSH) at no noticeable improvement in quality. DIN-rail mountable arduino clones and modules with I/O isolation that r…

Yeah Automation Direct is already in this space with their Arduino PLC[1] which has compatibility with their existing modules/etc. I'm only adjacent to the space and have use their stuff for some home automation but from what I've seen it's more important that you can get replacement parts and reliability. [1] https://www.automationdirect.com/open-source/home

$43 - $66

https://www.automationdirect.com/adc/shopping/catalog/progra...

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#75

Post by duskwuff »

mbanzi wrote: post #19
mikewarot wrote: post #2

I looked at the specs, I didn't see a dedicated processor doing the Ladder Logic / Modules part. Perhaps they dedicate one core to it... but that's a lot more janky than a separate CPU at about a dollar or two. I wouldn't want WiFi, Ethernet, or any other IO crashing the Controller. It has to be rock solid.

Hi the main processor is made of 2 separate cores and they can run different software. The processor we use it's the top of the line for STM so it's not a dollar or two. The separation between the two cores is much more well defined that people might think. The Wifi BT is managed by a separate module with its own separate processor (The Wifi/BT is also optional on most models)

> The separation between the two cores is much more well defined that people might think.

What separation do you think there is? The M7 and M4 cores on a dual-core STM32H7 share all of their peripherals and memory (with the exception of CCM and I$/D$ on the M7). There is virtually no separation between them; they can even run the exact same code with a bit of wrangling. There isn't even any provision for firewalling the two off from each other.

If you were planning on treating the fact that the part had two cores as a safety feature, you need to reconsider that.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#76

Post by akiselev »

liminalsunset wrote: post #35
gw98 wrote: post #18

I don't get the market position of this. A number of Chinese companies produce DIN rail mounted PLCs which already cover this market, cost virtually nothing and actually emulate Mitsu GX ones so work with existing off the shelf tools and have the same real time guarantees as the commercial units. If you're going to cheap out, these are fine. But this isn't the problem. The expensive bit of a PLC is the dude perma-wel…

I'm thinking (but can't confirm) that the intended market for these is companies that are too small to care about things like "well established vendors", where budgets are measured on the magnitude of hundreds of dollars and not thousands, and things are built from scrap or misc parts. I'm guessing that in some countries other than EU/Americas/etc, where things are done by "I know a guy that can figure it out", and p…

> For a small scale industrial process, even a really hacked together setup can work surprisingly well, and while you have a chance of running into some show stopping problem, there's an equal chance of the hacked together setup continuing to function for the required time. If labour to fix stuff and/or small enough scale to temporarily have a little downtime are effectively free, this can work out positively.

Can confirm that this is happening to some extent in biotech startups. Most of them don’t have the resources to hire grad students en masse to do the tedious labwork so they’re investing into lab automation. At the seed/series A level there usually isn’t enough money to splurge on brand name lab equipment beyond a few core pieces of equipment and with experiments running, there’s enough tech savvy downtime to experiment with hacky but cheap solutions. I’ve even seen HomeAssistant driven lab automation setups driven by AppDaemon apps with ESP32s used to control a mix of pumps and sensors (with CI/CD, though the whole thing was backed by a proper LIMS). It felt incredibly hacky but uptime was stellar once the SD card was replaced with an SSD.

It used to be that I had to go to Staubli or similar manufacturer and spec out a $50k robotic arm just to move plates from a liquid handler to the fridge. Now the same can be had for a few grand or less and there’s even open source options.

I see this PLC along those lines, where a lab might need to control a bunch of pumps and syringes with some synchronized via RS485 for realtime control and others on WiFi for less time sensitive stuff. A low cost PLC in that sweet spot between enterprise PLC and bare dev board could do really well.

These PLCs would be the perfect complement to ESP32s and RaspberryPi if they’re cheap enough to stockpile like RPis were preshortage. It’s unfortunate they haven’t published pricing yet, which tells me that it’ll be too expensive for hobbyists.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#77

Post by theamk »

gw98 wrote: post #18

I don't get the market position of this. A number of Chinese companies produce DIN rail mounted PLCs which already cover this market, cost virtually nothing and actually emulate Mitsu GX ones so work with existing off the shelf tools and have the same real time guarantees as the commercial units. If you're going to cheap out, these are fine. But this isn't the problem. The expensive bit of a PLC is the dude perma-wel…

I think this is an attempt to break monopoly of those traditional PLCs. There are definitely going to be good use cases for ladder logic and "tried and true" programming model which was hasn't changed since 1990's. And in this case you are correct, the new Arduino makes little sense.

But sometimes you want something more modern, that you can program in the same language your main product is in, and apply the same expertise and tooling you already have.

I am not sure Arduino is the best option, given that their ecosystem is often very low quality, but there is definitely space for regular MCU in rugged case with protected I/O.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#78

Post by DannyBee »

HeyLaughingBoy wrote: post #53
DannyBee wrote: post #32

Earlier quoted context omitted.

That's unfair - I read the description at length, and quite honestly, I still can't understand why i'd ever use it. It looks like buzzwords over real use-cases. The partner, Finder, is known for making these types of devices, and outside of the "Arduino" stamp, they've made a device that has been in-market (and relatievly unused) for half a decade already. This will not be a real option for IOT. For what they are try…

> At a slightly higher level, NRF does a much better job of producing rock-solid devices and ecosystem that can do bluetooth/wifi well, and throw in I/O. Minor nitpick just because I want them to be credited properly. nRF is the product, nordic semiconductor is the company.

Yes, you are correct, i typed it too quickly.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#79

Post by liminalsunset »

gaze wrote: post #67
gw98 wrote: post #18

I don't get the market position of this. A number of Chinese companies produce DIN rail mounted PLCs which already cover this market, cost virtually nothing and actually emulate Mitsu GX ones so work with existing off the shelf tools and have the same real time guarantees as the commercial units. If you're going to cheap out, these are fine. But this isn't the problem. The expensive bit of a PLC is the dude perma-wel…

What are some good keywords to search for if I'm looking for some of these knockoff PLCs?

You can just go put "PLC" into AliExpress and you will get a bunch of FX01 clones, or you could put "GX Developer" since all of these seem to be compatible.

Unfortunately GX Developer doesn't appear to be free, but apparently Delta makes PLCs too (with actual UL certs too) which sell for about 130 USD on AliExpress and the software appears to be free (unsure). They also have reasonably (~80$) priced HMI LCD touch screen displays.

Re: Arduino unveils the Opta – “Micro PLC” for industrial IoT

#80

Post by DannyBee »

LeifCarrotson wrote: post #13
DannyBee wrote: post #3

I do a lot of PLC work. The Arduino IDE is totally unsuitable for it. No idea what they are doing about this. It would take an amazing amount of work to fix this. As for PLC functionality people actually use, the product page says "Optional support for standard IEC 61131-3 PLC languages". This is what folks use for real. I presume this means "we didn't want to pay CodeSys but you can". Or something. That sucks. Maybe…

An amazing amount of work is being done, apparently: From this LinkedIn post [1], they say: > It will soon add PLC IEC 61131-3 programming (full set of 5 languages) + no/code fieldbus + Arduino sketch integrated with shared variables. There will be a new Arduino PLC IDE for that. I also do a lot of PLC work. I agree that this isn't going to replace my CompactLogix, S7-1500, or Beckhoff controllers...ever. But there a…

Interesting. Given how much work that is, i have to imagine it's integrating a custom codesys (like beckhoff used to do) or something.

Hard to believe they could do it all on their own that quickly.

As for the rest - no disagreement, In practice though, i would trust the P1AM/etc over Arduino's product every day of the week. This is what they do.

The thing is that if i needed something a little different, i'd just move to a different part of the Productivity line - a p1000 or p2000 or a p3000 (or something else from Koyo, who owns them all).

If i needed ability to do "random things", i'd use a revolution pi, as you said.

There are plenty of good things in this market, and arduino doesn't seem to actually bring anything meaningful to the table.

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