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Comment by dheera | Hacker News Reader

I also wish these types of boards (including the Pi itself) would move away from USB-C ports and barrel jacks and move to something a little more suited for industrial embedded purposes. Anything from an XT30 to JST-EH to Molex Mini-Fit Jr. would do.

USB-C ports are flimsy and I've had many just snap right off the board, especially given the massively long cantilevers that most USB-C cables are. They also massively increase the effective footprint of the board when plugged in.

Or at the least, have the USB-C connector but provide something else as an option. I know the Pi can be powered off the GPIO, but it's not ideal as it bypasses all the power filtering circuitry.

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The Raspberry Pi is available in an SO-DIMM form factor for embedded applications.

https://www.raspberrypi.org/products/compute-module-3-plus/

I wish the pi 4 was available in a compute module, it’s a great idea.

Yes, but how will you cool it?

That shifts the problem elsewhere (now you need a carrier board with additional electronics), but it doesn't solve it.

The pi form factor is fine, but 2-pin Molex-type connector in parallel with the incoming 5V would be a great addition. Hell, even just leave pads or holes and I'll solder in a connector myself. RPi's are being used more and more in embedded applications. It would be nice if the Foundation acknowledged that and made it a bit easier to work with.

The Pi can be powered by 5V through the expansion connector at pins 2 and 4 (with pin 6 and some others for ground). You can also get/build a 'hat' for your embedded application that provides power over Ethernet, 24V screw terminals with a regulator down to 5V, or whatever connector you require.

However, I disagree that the Molex connector is inherently superior to USB-C. I am abundantly familiar with the incongruity of a wall wart in an embedded application, but all you need for the power supply is 5V delivered over a USB-C connector. I understand an appeal for a latching or screw-secured connector, but a pin header connector is neither of those. USB-C doesn't easily fall out, it's just another connector.

Another answer is to hack a USB 2.0 C-C cable [1] in half, pull back the shield, heat shrink over the shield and 30 AWG data wires, crimp ferrules on the 26 AWG power wires, and run those to my screw terminals of the existing embedded 5V power bus.

[1] https://www.monoprice.com/product?p_id=27907

To build on that, you can also secure the USB-C connector with a small dab of epoxy or locktite. Many devices I've pulled apart put a dab of epoxy on connectors to secure them so it's a known technique. A small dab still lets a technician break it if need be for repairs.

The USB-C connector is surface-mounted, so that makes it super easy to be torqued off by the massive cantilever that is the USB-C plug. I regularly have entire connectors ripped off PCBs but that has never happened with cheap, industrial connectors like the various ones Molex produces (and they're dirt cheap).

Molex has very sturdy through-hole power connectors as well as plugs that are lower profile and won't torque off the connector as easily. 2-pin Mini-Fit Jr. would work pretty well.

Or XT30 even. I love XT30 connectors.

Just need a case that supports screw down connectors like these

https://www.amazon.com/JSER-Type-C-Locking-Connector-Standar...

Issue solved.

The mission of the Raspberry Pi foundation is to provide cost-effective computers for use in education. I suspect the foundation's non-profit status or at least community goodwill would be threatened if they decided to design and market hardware to industry.

Moreover, Raspberry Pis were never intended to be used in industry, and obviously are not designed as such. They _happen_ to work in many use cases, yes, but they lack so much: reliability engineering, failure testing, ruggedness requirements, industry certifications, QA, I could go on.

And, do you really want to be the guy who gets the call because failure of a $35 part stopped the production line at 2 a.m.?

There is no lack of industrial computing gear on the market, even stuff that runs Linux. It will cost an order of magnitude more for the same computing power, but it is more rugged, integrates well with existing systems, and is sold by a vendor that you can actually get on the phone and hold accountable for some things. And most importantly, putting it into production probably won't get you fired.

> but they lack so much: reliability engineering, failure testing, ruggedness requirements, industry certifications, QA, I could go on.

Sometimes you don't need all that stuff. Sometimes it's as simple as using a neural net to count the number of people in a room at a given time, or get a sensor to publish data online, or provide a networking shim for a RS232 device that fits in a small space.

There are also many use cases where having 10 working backup copies of a $35 device on a shelf that can be swapped in under a minute is a much better reliability guarantee than 1 $2000 industrial certified, QA certified, FDA approved, UL listed, GDPR compliant device whose tech support is in some other timezone, takes holidays, and isn't 24/7.

It's just that the easiest thing that can fail on a raspberry pi in my experience is the stupid micro-B/USB-C connector, so fixing that, which would cost pennies to put a slightly more rugged molex or other connector on the PCB, would be a really nice addition. The rest of the Pi is actually pretty reliable in my experience.

> stopped the production line at 2 a.m.?

Production lines aren't the only use case for Raspberry Pis in industry. Many production lines also don't run at 2am.

On rpi(at least rpi3) there is actually a debug point (a designated point on the board with some solder on which can be connected quite reliably) which allows for supplying power through it, while also taking advantage of all the power protection circuits that the USB port takes advantage of. It might be something you want to look up.

I am legitimately curious to see if you believe that the PI is suited to actual industrial applications in terms of its reliability (filesystem etc...) and low cost design? Maybe I'm defining industrial as something a lot more PLC based vs something akin to 'monitor the temperature in the warehouse' of course - when I hear industrial, I immediately think steel mills or manufacturing plants.

I would strongly hesitate to recommend the Pi for anything situation where 99% reliability (or above) was required unless I understood the domain back to front and could cover all the failure cases such as the expected operating environment ranges (temperature, power quality, EMI etc...).

Raspberry Pi is available in a "compute module" format which uses a standard SODIMM pin package... They sell quite a lot of them to commercial clients for use in manufacturing. Close to half of all Pi are used commercially, by some accounts. Stable form-factor, excellent documentation and ability to order new stock of specific models for several years after release make it very popular.

For example, I put embedded computers on drones and the first thing I do is have to figure out how to get power in that avoids the barrel jack which will almost certainly vibrate itself out. On the Pi (and most boards) that means direct power via the expansion header, but usually that means making a daughter board PCB with a suitable connector plus input protection (fuse, diode, etc). Not industrial, but any situation where you don't want to provide mains power, and you want a reliable connection means avoiding the jack.

Can you desolder the barrel connector and put on a locking molex or something?

You can, but that's irritating to do. In the case of the Pi there is no barrel connector, it's a USB port. So your only option is the header, either directly into the holes if its unpopulated, or get a 40-way female header and solder to that, or go for a daughter board.

This is one of the problems that arise in these discussions and I'm glad you clarified what you were thinking of.

"Industrial" spans a wide range. The problem I run into is that when I mention using Arduino or pi in industrial applications, people immediately jump to thoughts of extremely harsh environments and safety-critical applications. There are plenty of existing solutions to those problems.

Where the Pi shines is in "light industrial" tasks that a standard PC would be unsuited for (cost, size, I/O, power consumption, etc), but the environmental requirements aren't stressful. Those can be anything from counting rebar loaded onto a rack or providing help to truckers at a loading dock.

Even so, I have lots of small devices (arduino clones, Raspberry Pi) in machine control applications and they've been working very well.

The standard Raspberry Pi IMO isn't suited for industrial uses, but the compute module combined with a board designed with this kind of use in mind is a good start.

Looks like the DFI board in question uses a 2-pin screw terminal block for power, 12v +-5%.

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