How long is the USB3 micro-B plug supposed to be

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DanNeely

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I recently bought a USB3 hub that uses the older micro-b style plug to connect itself to my PC. The cable that came with it was on the short side so I ordered a longer one to replace it. The new cable kept dropping my connection; while troubleshooting the problem I discovered that its plug was about 1mm shorter than the one that came with the hub. I want to know what's out of spec, the longer cable I got or the hub itself; so I know who I should be sending a complaint to.

The cable that came with my hub is on the right; the longer one I ordered from amazon on the left:

LxHs08S.png
 
I'm quite capable of finding huge images of cables with and without full depth grooves all over the net on my own, thank you. What I'm trying to do is to find out what the USB spec says the connector length should be, so I know if I should be requesting a new cable because the first one I was sold was defective, or flaming the hub manufacturer in a review for using a socket designed for a non-standard cable that behaves poorly with ones that are standard compliant.
 
Okay, here. Official USB 3.0 Micro-B spec drawing.

IyZiH4t.png


I think this means the spec is a minimum of 5.4 mm, and that there's no maximum - probably to accommodate the possibly that a device might have a socket recessed further than usual.
 
Where'd you find that? I looked for official specs unsuccessfully before posting here.

I'm rather surprised, and mildly skeptical that they wouldn't specify a maximum length because anything that was designed for an extra long plug wouldn't work with most other cables. Maybe a maximum size specified in the socket diagram instead.
 
This page -> the link to the pdf file "Universal Serial Bus 3.0 Specification" -> USB3_r1.0_06_06_2011.pdf -> page 106.
 
Flipping through the rest of the mechanical specification section of that document, on p 107 it shows the socket as being 5+-0.3mm deep. p 138 shows the socket and plug mated; and requires a minimum of 1.3mm between the plastic part of the plug and the edge of the socket. From looking at the hub, it appears that the plastic body is about 1.5mm deep. To eyeball precision that's within spec; so it appears that the problem is the internal socket itself being too deep.

A quick check in the 3.1 spec doesn't appear to add any additional constraints to the connection; but I'll look at that in more detail later on.
 
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