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Hi there. I'm an engineer on the Revolution Pi team. AMA.
One of the reported issues with the Raspberry Pi is failure of the SD card if power is interrupted while the card is being written. Does your implementation overcome this problem?
Industrial? Nope.
Hi there. I'm an engineer on the Revolution Pi team. AMA.
Nice idea! One of the reported issues with the Raspberry Pi is failure of the SD card if power is interrupted while the card is being written. Does your implementation overcome this problem?
Of course the eMMC is still based on flash, which has a limited lifetime. So we use a customized version of Raspbian which has swap disabled by default (can be enabled if you need it) and tunes the syslog configuration to reduce the amount of log data written. It's also possible to use a tmpfs-backed /var/log (can be enabled with a mouse click or a simple command). That way we try to prolong the lifetime of the eMMC as much as possible.
We've also been in talks with the Foundation about this and they have asserted that the eMMC is of good quality and should last for the typical lifetime of a PLC (which can be decades).
How industrial are we talking? Is it certified for use in industrial environments? I saw a few mentions of IEC61131-2, but I couldn't find whether it actually has certifications. If it is suitable for use in the industry, I can't wait to ditch ladder and Structured Text in favour of modern programming languages for industrial controllers.
This was answered in the German Revolution Pi forum a few months back: https://revolution.kunbus.de/forum/viewtopic.php?f=8&t=6&p=1... The TL;DR is that the products have gone through all the testing required by EN61131-2 and you can safely deploy them in harsh environments (e.g. wrt electromagnetic radiation or vibrations/shocks). However there is no external certification.
How industrial are we talking? Is it certified for use in industrial environments? I saw a few mentions of IEC61131-2, but I couldn't find whether it actually has certifications. If it is suitable for use in the industry, I can't wait to ditch ladder and Structured Text in favour of modern programming languages for industrial controllers.
They seem pretty solid in terms of their specs and certifications, but for industrial equipment I'm always worried about availability and vendor support. Can I get them shipped to a customer anywhere in the world on short notice? Will my vendor's engineers come to the plant with me to solve an inscrutable issue that has brought a machine down? Those answers are "yes" for the systems I'd be replacing, and almost certa…
As to availability, the hardware is manufactured and assembled in Denkendorf, Germany, so the supply chain is short. The Foundation guarantees availability of the Compute Module 1 and 3 until at least January 2023.
Earlier quoted context omitted.
I saw that you mentioned running Hadoop/Spark on your cluster? Do you have any comments on that? I just made a 3 node RPi3 cluster and I have to admit, it's really slow. Like getting the spark Scala interpreter running takes about a minute before anything I type registers in the console. (NOte: this is my own cluster not a PicoCluster TM)
When all 4 cores are under load, the BCM2837 on the Raspberry Pi 3 will rapidly reduce the clock rate after about 60 seconds (from 1.2 GHz to 600 MHz, or even 300 MHz if the core temperature exceeds 85 degrees Celsius). Cooling is required if you want decent performance for prolonged periods of time. The RevPi Core 3 is equipped with a high performance cooler which is able to sustain 1.2 GHz at full load for about 20…
Earlier quoted context omitted.
They seem pretty solid in terms of their specs and certifications, but for industrial equipment I'm always worried about availability and vendor support. Can I get them shipped to a customer anywhere in the world on short notice? Will my vendor's engineers come to the plant with me to solve an inscrutable issue that has brought a machine down? Those answers are "yes" for the systems I'd be replacing, and almost certa…
Both the hardware (base board schematics) as well as the software are open source. Let's say Kunbus goes down the drain and you hit an issue. Best case someone in the community has already fixed it. Worst case you'll have to hire a decent consultant. Show me another PLC that affords the same kind of vendor independence. As to availability, the hardware is manufactured and assembled in Denkendorf, Germany, so the supp…
Hmmm. I'd be curious to know who ends up using these devices. Maybe I could apply to work for them. :)
+55°C max operating temp Industrial? Nope.
Earlier quoted context omitted.
Both the hardware (base board schematics) as well as the software are open source. Let's say Kunbus goes down the drain and you hit an issue. Best case someone in the community has already fixed it. Worst case you'll have to hire a decent consultant. Show me another PLC that affords the same kind of vendor independence. As to availability, the hardware is manufactured and assembled in Denkendorf, Germany, so the supp…
Well, I really like the idea of a standard open source industrial control system. If we ran into vendor/supply issues, that would give us options. But this industry (or at least the pocket of it that I work in) is very conservative. It's like the old "nobody got fired for buying IBM." Hmmm. I'd be curious to know who ends up using these devices. Maybe I could apply to work for them. :)