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We like to use the rpi for an industry application (process monitoring). Our requirements are:

  • power supply from 24-48 volt
  • powerdown mechanism to protect data from an outage (safe automatic shutdown with battery or condensator when there is an outage)
  • housing for rpi and power supply mountable on a din rail

Is there such a packaged solution on the market today? Or do we have to build our own?

EDIT: Thanks for your valuable feedbacks. We don't use the RPI in production for now. I'll start a new thread for a commercial alternative to the RPI that fits to our scenario.

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    How can you expect $25 equipment to be commercially ready? The Pi was designed for educational purposes for 3rd world countries. There are better things that are more robust and come with commercial support. The Pi is a bad choice and if anything goes wrong you can only blame your self. – Piotr Kula Feb 10 '14 at 10:58
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It's 2020 and I know the question was asked a long time ago.

We like to use the rpi for an industry application (process monitoring)

Nobody can stop you from doing so, there might be better but also worse alternatives depending on the task at hand. As for the questions:

1. power supply from 24-48 volt

Search: "din rail dc power 5V" (you don't want to convert power multiple times)

2. powerdown mechanism to protect data from an outage (safe automatic shutdown with battery or condensator when there is an outage)

If the raspberry pi is mounted inside a cabinet with a main switch and you want to use it to also power the Raspi on/off safely, you could build a circuit that takes advantage of overlays:

enter image description here

In this example pulling GPIO pin 21 to low causes a shutdown and after the shutdown GPIO pin 20 goes to high (I'm not an electrical engineer so I removed the circuit posted here previously).

Another option is to set the file system to read only which is easily done in the latest OS using the GUI of the Raspberry Pi Configuration: Performance/ Overlay File System.

For dealing with (potentially homemade) problems resulting in a hang (memory leaks and the like) you could take a look at the built in Watchdog feature.

3. housing for rpi and power supply mountable on a din rail

Search: "din rail raspberry pi", there are plenty of boxes / housings to choose from.

Is there such a packaged solution on the market today? As for the powerdown mechanism there is a lot out there but I didn't find anything ideal yet (at least not for me). Some don't completely cut power resulting in the Raspi not booting up again, some use Lithium batteries that I don't want, the energy stores tend to degrade over time a.s.o...

For a recent din rail mounted project I simply use a read only OS file system together with a dedicated ext4 partition for an sqlite database file How To Corrupt An SQLite Database File.

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no matter what power supply and housing you'll choose, Pi is a cheap media player, that's not intended for any other purpose except getting familiar with Linux and programming and occasionally watching some music or listening to the movies.

unless you don't really care about the process monitoring and have someone with a pack of freshly re-imaged SD cards nearby in case of system disk failure, I'd recommend to choose another hardware solution.

  • I completely agree with this. The Pi must not be used in commercial applications. It was designed for educational purposes. If you wish to use it commercially you must support it your self. If anything goes wrong, you must fix it your self, any mods, make it your self. – Piotr Kula Feb 10 '14 at 10:56
  • I agree, but can't upvote as it doesn't answer the original question, just tells you the truth. – Canadian Luke Feb 10 '14 at 16:04
  • Is the Beagle Bone Black a better platform for industry applications? At least the connectors are better placed for housings compared to Raspberry Pi. – WeSee Feb 13 '14 at 23:22
  • @WeSee a good industrial solution starts from several hundreds $$$, it's very unlikely you'll find anything good in $25-50 price range. – lenik Feb 14 '14 at 0:32
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TL:DR

A Do-able project for in house, home automation that's unregulated and completely unsafe under OP's specs. To make it work one just needs to get a few parts, write a pm-util script, and follow guides on powering a Raspberry Pi by battery as listed below.

Answer

This is not my main account, so I do apologies for the lack of quality in the post's layout/link structure.

However, since I'm a big proponent of DIY COTS IoT projects especially ones using the raspberry pi. Thus I had to comment on this..

  • Power supply from 24-48 volt, that is the quickest way to start a fire! The RaspPi is a 3.3v 1.5A device (all versions as of 2015). The closest to an applicable resemblance to an IoT/Scada use case is on the raspberrry pi form itself https://www.raspberrypi.org/forums/viewtopic.php?t=36225. Though the pi would still take a 5v rail only and anything more will let out the magical genie in very scarry ways.

  • Raspberry pi and safe shutdown is relative. Being that its a solid state device using a sdcard and depending on the distro configuration (ie debian or arch linux arm) could be using ext4 fs or something more fault tolerant(ie extreme datacenter usecase fault tolerant) as the filesystem.

  • One could write a pm-util script in python to send a signal over a GPIO pin for when the board enters into any of the ACPI power states: https://www.raspberrypi.org/forums/viewtopic.php?t=64051&p=473743

  • As for battery usage, there has been attempts to add battery power and solar power at that to different projects. Hackaday has a good write up on this at https://hackaday.io/project/5970-weatherpi-solar-powered-raspberry-pi-station

  • Just get yourself a Bud Industries AN-1302 case and some acrylic risers. Then drill the case for mounting to your din rail, custom built power supply, and pi board.

Other things to note

As everyone else has pointed out on this post the Raspberry Pi is a cheap COTS "pc" with GPIO boards designed to be an educational tool or simple DIY toy in the same spirit as the old TRS-80/C64/Altair 8800. Any resemblance to an actual end product is only relative to one's licensing with the "RASPBERRY PI FOUNDATION" and Broadcom. Plus these boards and custom project would not be UL licensed or safe in any fashion for scada environments as defined by most governing bodies. Therfore if it breaks or damage anything then as with all in house built solutions; one has to remember it is your team's responsibility to support it.

All in all using the same design concepts highlighted here would be great for one's makerspace or home automation. Plus, if your hire-ups are willing to back the use of a DIY solution then all the more power to you.

Update

Earned a few points so now I'm able to use advanced editor options and clean the response a bit.

Update 2 There is a raspberry din rail case instructable available.

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