Testing USB cables before connecting to Arduino

I'm going mad with my stack of USB cables, most of which seem to be either charge-only or damaged. If this question belongs in a different forum, then please point me to the correct form.

Does anybody have any experience with either of these two USB cable testers or something similar?

"Data Cable Detection Board USB Cable Tester For iOS Android Type-C Short Circuit On-Off Switching Test Board Tool"
https://www.aliexpress.com/item/1005005056927271.html

"MECHANIC DT3 Data Cable Detection Board USB Cable Tester For iOS Android Type-C Short Circuit On-Off Switching Test Board Tool"
https://www.aliexpress.com/item/1005004129738498.html

They are both under $5 so I don't expect much. But is there anything that one should look for in a USB cable testing tool? Ideally I'd be able to test if the cables work with other devices as well, so maybe I should look for a device that checks high-speed data? I'm not really concerned with power delivery or other features like HDMI forwarding.

Thanks.

All that is necessary is that the individual wires in the cable have continuity, are not shorted, and are in the correct order. So either of those will do the job.

They are just wires, no electronics so once you've tested for the above your done.

I have a simple solution for me. When it does not work but charges I place a piece of Red tape on it. If it works and uploads I place a piece of green tape on it. I have many cables, this helps a lot. Also when I connect one and it is working I leave it connected. Simple trick is program one or two Arduino with something that sends a hello world type message about every three seconds. You can see the led blink and the serial monitor will open even if wrong item is selected. I standardized on 115200 as the baud and mark anything that is different. Good Luck!

Great, thanks. I thought maybe there is some internal resistor or some other way that high-speed cables might be distinguished from low-speed cables by the connected devices.

Yes, I plan on marking them with nail polish. I'll standardize on your colour scheme, thank you.

Maybe I'll see if I can carefully roll a 3mm ID O-ring over the USB connector onto the cable - might actually be possible on a USB-C or Micro-USB cable. Now to find green and red O-rings ))

Why not simply throw away the power only USB leads so that all your remaining ones work with the Arduino and for charging ?

Some (but who knows which?) charging cables have heaver wire than standard data cables for high speed charging.

Because I often need to simply power devices, and my children and neighbours already know me as the guy to come to for anything tech related. It's good to have these on hand.

As for keeping them separate, well, I'd like to test them first. And there will be new cables, misplaced cables, etc.

Yes, that might help to find the fast-charging cables. But now those heavier cables impinge on the old rule of thumb that the thicker cables supported data.

I suggest otherwise. Cable design is a whole subject by itself and involves things like conductor material and thickness, insulation material and thickness, wire twist pitch and direction of twist. For example if you open up cat 5 or cat 6 cable you will see the different colours are twisted at different pitches to reduce crosstalk. Conductor material and thickness affect resistance, which is important for delivering power, while thickness of signal wires and thickness and material used for insulation affect characteristic impedance.

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I do agree with your post, but how would you non-destructively test for these things?

Perhaps by sending data down the wire? Though I do agree that a device capable of doing this will be far more expensive than the simple $5 testers shown above.

Heat shrink.

With very expensive test equipment! Not worth it unless you are buying lots of cables and need to verify they meet the required standards.

The main reason for my comment is I don't want beginners to think that cables are just bits of wire and it doesn't matter. It does matter and people get caught out buying cheap crap then wonder why they get problems.

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For different purposes I've used colored zip-ties. (Not as "nice" as heat shrink.) Sometimes I've used red for a right audio channel (if the cables aren't color coded or otherwise identified). And on my workbench at work I've got several similar cables with a "random" matching-color zip-tie on each end. The colors don't mean anything but I can identify both ends of the same cable.

I don't have any charge-only USB cables and I don't remember if I've ever had a bad USB cable! ...That seems weird to say because cables and connectors are usually the 1st thing to fail, and I'm aways telling people to "try a different cable".

But you don't need separate cables for charging when full function cables can do the same thing

I doubt that heat shrink small enough to catch the wire well, will slip over the USB connection.

Right, but sometimes the daughters need just a charging cable to take to their boarding schools - waste of a good data cable to give to them. And I don't want to waste a good data cable on the son's or the wife's charging where the cable is going to be heavily abused. Or when a neighbour needs one - and I happen to like being the "go to" guy for some technology things (I won't touch Windows).

No Windows? What about cabinets?

Sure, cabinets are fine )) They are less associated with bugs than are windows!

That's it, my new OS will be called cabinets, and all errors will be dubbed "termites".

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