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It's because it's way, way cheaper and more flexible to use a touchscreen PLC, like one of these: https://www.automationdirect.com/adc/Shopping/Catalog/HMI_(Hu
by LeifCarrotson 9y ago
It's because it's way, way cheaper and more flexible to use a touchscreen PLC, like one of these:
https://www.automationdirect.com/adc/Shopping/Catalog/HMI_(Human_Machine_Interface)/C-more_Touch_Panels/C-more_Touch_Panels_EA9_Series/C-more_EA9_Series_Touch_Panels/EA9-T7CL-R https://www.automationdirect.com/adc/Shopping/Catalog/HMI_(H...
than a huge mess of buttons and wires.
Just look at that linked product! Less than $500 and you have as many buttons and labels as you can shake a stick at, and it's all behind a pretty color display. I can hardly buy 3 buttons, a vinyl overlay, and pay for the labor for the wiring of that stuff (plus the PLC that you'd now need behind it all) for $500. Much less pay someone to make physical modifications to the completed machine when someone decides they need 4 buttons.
You say it's the fault of the "UI designers" who think they're working with pixels and X/Y coordinates. The situation far worse than that! The person who writes the UI for these is probably an EE thinking in terms of the primitive ladder logic that drives the machine. And it doesn't help that the software you use to configure these things is pretty terrible.
- FussyZeus 9y agoHonestly I have zero beef with touchscreen interfaces, some are a little clunky but I've never found one I couldn't figure out. That said, DUMP THE GODDAMN RESISTIVE SCREENS IN THE TRASH. Seriously those things were fucking garbage when they were invented, now that we have capacitive screens, there is NO REASON WHATSOEVER to keep making me endure the touch technology of 2001. While we're at it get them out of my fucking car too.
- moduspol 9y agoDon't you want to be able to control your radio with gloves on?
- FussyZeus 9y agoThey make gloves that can work capacitive screens, and they aren't even expensive anymore. Meanwhile resistive screens suck just as hard with gloved or ungloved hands.
- yellowapple 9y agoResistive screens don't help with that in practice. Physical buttons do.
- FLUX-YOU 9y ago>Less than $500 and you have as many buttons and labels as you can shake a stick at, and it's all behind a pretty color display. A raspberry pi + touchscreen is 1/5th of that. RPi is capable of running Qt5 which would be a solid UI choice. How the heck have they survived?
- LeifCarrotson 9y agoA few reasons: Because a Raspberry Pi and Ebay touchscreen won't be running or supported in 20 years, while the PLC will. The IO on a Pi needs optoisolators and hardening that's built into the PLC, and it needs soldering, while the touchscreen has built-in screw terminals. And while the software sucks, anyone remotely competent can go from zero knowledge to bumble into a working, sturdy product on the PLC in perhaps 80 hours. Qt has a much steeper learning curve. Essentially, the touchscreen is an RPi and touchscreen, plus some industrial enclosure, strengthening, and connectors all wrapped up into a product. That integration is definitely worth $400. Or, if you want the name brand stuff, the Allen Bradley version of the same will set you back another $2000.
- jpindar 9y agoIn addition to all the features you'd have to pay someone to add, and software you'd have to pay someone to write, what are the noise immunity, temperature, shock, vibration, and emission etc. specs for a RPi? Does it have UL, CE, etc. approvals? Does it have a warranty? Does it still have all these things after you've modified it?
- HeyLaughingBoy 9y agoThe same way I was able to buy a $30 display and sensor off AliExpress, install it in a $5 plastic box, test it and resell it for $120. Value was added. Sometimes, simply knowing what product to purchase is worth hundreds of dollars.
- jpindar 9y agoOooh, that is a nice one.