Linux

Ignition from Inductive Automation. Works great on Linux, used to run it in docker even. There are drivers for all kinds of PLCs. It's a dream to develop in, was my SCADA platform of choice (I've moved on from the industry). If you need to script anything, it is in Python, not some bullshit proprietary scripting language, nor VBA garbage. The client software is great, even runs nice on PC-based HMI touch panels, which you could install Linux on if you want. The call-out alarming actually works (FUCK WIN911).

The software is free to try and download. You can develop in it for free, unlike the majority of competitors. Go ahead and try all of it out right now if you want. The training courses on using their software are free, nice handy videos, so you can start learning how to build everything like right now.

The "catch" is it costs money to run all of the SCADA critical components for more than an hour at a time (to prevent you from just using it to run your whole plant for free). But you can build your whole SCADA app today with your PLC gear on hand, and only pay for it once you are ready to deploy to production.

Anyway, to me, it's hands-down the best SCADA platform, and it even runs on Linux. Disclaimer: some of this might be out of date, I've been gone about 4 years.

Edit: sorry, didn't see the "free" requirement. I would never run a critical plant without support, so I've not explored any fully open source options. If your plant is serving more than just your farm/homestead (in other words, is serving the general public) I strongly recommend a supported option for your client. If you get hit by a bus, and the plant is in trouble, they'll have a hard time finding someone to get them back online who knows your "weird" software.

That said, depending on your needs, Ignition can be cheap AF (comparatively) if your plant is small.

ScadaBR is an open source and cross platform scada that was successfully deployed in a water treatment station. Check it out.

Really? If it's a big enough treatment works to warrant a SCADA, then I doubt an automation engineer with the experience to set it all up would be asking this question, but here goes. You've a couple of obstacles:

• every contract I've ever seen for industrial automation has either specified which control plane they want directly, or they'll have a list of approved suppliers which you must use. Someone after you will have to maintain this. Those maintainers will only accept the things that they have been trained on. Those things are Windows PCs running Windows software. They will reject anything else. The people running network security on those machines will have a very short list of the acceptable operating systems for running SCADA systems. That list will be a couple of versions of Windows Server. They will also reject anything else.

• that's not nearly enough information to make a recommendation. Which PLCs? Allen Bradley, Siemens, Mitsubishi, ...? I can't think of a job I've ever been on where the local HMI hasn't matched the PLCs. The SCADA software almost invariably matches the PLCs used in the main motor control centre, with perhaps a couple of oddball PLCs for proprietary panels and such like. Could maybe ask the supplier if they've a Linux alternative? Siemens will laugh at you and Mitsi won't understand the question, but AB just might.

Sorry - I'm a Linux evangelist, but I don't think it's a good fit for here. SCADA performance generally isn't bad due to Windows Server - it's fine, does what it's intended to - but because eg. STEP 7 is an appallingly slow and bloated piece of software which would bring a mainframe to its knees. Which is bizarre - the over-the-wire protocol connecting the machines is generally a short binary blob described in the PLC configuration - these bits are the drive statuses, these bits are an int or a float for an instrument readout - and it shouldn't be at all slow updating it all, but slow it is.

What you are looking for is Ignition SCADA. Specifically the perspective module. It is the best in the market in my opinion, has unlimited tags, great training videos and runs on almost anything. It also comes with the drivers needed to connect to most of the popular brands' PLCs.

I have seen this implemented at wastewater and water treatment plants

However a SCADA will be pricey, if it's a small plant rather consider an HMI, there are options available from Ignition's side, but it'll depend on how much it is worth to you

Not an automation guy here either but I have worked with several, and my current workplace has a big boner for Ignition, which runs on both Linux and Windows and works with their Allen Bradley PLCs. They run the whole thing on Linux VMs on VMware, with their HMIs being mostly Windows PCs, but as far as I can tell all they really need is a web browser, so you could probably use anything for that.

Ignition isn't free but they have trial versions and a free 'maker' version that I can only assume has commercial use exemptions or something in it.

A new window into the [email protected] community has appeared 😹

As others have said, Inductive Automation 's Ignition is a fine SCADA platform that runs on Linux. I used it for years until my employer decided we should get rid of Ignition and use OSISoft Pi for data visualization. It's a ridiculous idea, as they are different products with different use cases, but I lost that argument and have been told to drop it. Still salty, all those development hours and useful tools gone.

Just install Gentoo. It will fix your problems.

Honestly though I have no idea what you are asking. Maybe custom built software?