USB 3.1 with penetrators?

Blue Robotics Products WetLink Products
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I have already found this thread Making a waterproof USB 3 cable , but it’s pretty old and also not really been resolved, so starting a new one with a slightly different take.

We are looking to feed a USB 3.1 cable into an enclosure underwater (USB-C goes there), the other end (USB-A) is above the water. This means making the opening where the cable enters the enclosure watertight, of course. Naturally I have tried fitting a 5.5 HC penetrator, which fits the cable pretty well.

However, I had to cut and resolder the cable to fit the pentrator. This has ruined signal integrity and now the cable is only usable in USB 2 mode, which i snot good enough for our application. I don’t think soldering on a USB-C plug to one cable end instead of connecting the 2 cable ends would improve the situation enough to get a signal.

So, does anyone know of a solution to our porblem? A USB 3.1 C to A cable with a pre-applied penetrator would nice, of course, but that doesn’t seem to exist. Maybe some screw-on watertight USB-C cable+plug product?

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Hi @jobotics -
USB 3 can be quite tricky! The wire impedance of twisted pairs is dependent on the # of twists, and so cutting and soldering it back together can negatively impact this as you’ve found.

I’d think that finding a long USB 3 cable with proper (high) number of internal wires, and cutting the very tip of one end off, passing through a penetrator, and landing on something like this breakout is your best bet for success. Note you’ll be connecting a lot more than 4 wires for power and D+/D- to get USB 3 speeds, I believe…

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Yeah I figured this much. With the breakout, I wasn’t able to find a good source of which wire goes where (so which color of wire is which denomination).

And, honestly, it’s not so easy to solder to such a breakout’s tiny pads (the one you’ve linked might be better than the one I have available right now) – especially with the penetrator dangling off the cable really close by.