Longest USB cable, and USB hubs

So got my X-carve all hooked up and spent most of the evening troubleshooting. Turns out I had a USB extension cable hooked up so I could have the pc as far away from the x-carve as possible. and I also had to get rid of the 4 port usb hub I was using. since my surface pro tablet only has 1 USB port, I was using the hub so I could have a mouse as well.

Couple of questions

What would the longest USB cable I could get away with?
Would a Usb cable with a repeater work?
I was using a brand new anker USB 3.0 4 port hub(not powered) do you think a hub would be ok if it was powered?
or should I just go with a bluetooth mouse?

Basicaly USB carries 5VDC for relaying data. Mostly desktop PCs have no problem with extended lines. In this forum I’ve seen many discussions about stop and go connections with laptops.
My personal opinion; using externaly powered USB hub is the best way to do it. Doesn’t cost too much any way. I have Powerful Desktop with USB 3.1 and dual monitor, I’m using powered USB hub. Never have problems.

Presently, I am running a 12-foot USB-B cable to a powered hub on my ceiling, with another pair of twelve footers routing down to the X-Carve, and my laser. I’ve had no trouble at all with this setup, nor the earlier twelve-foot-plus-six extension with no hub.

  • Maximum cable length for USB is about 16 feet (the standard defines 5 meter)
    for each cable section between 2 hubs.
  • But: this is the theory assuming home and office environments.
  • In reality USB is very very susceptible to electromagnetic interferences - and CNC machines create a lot of it.
  • So: the better the cable, the better the grounding and shielding of your CNC power electronics, the longer the achievable cable length.
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I built my son’s cub scout pack a pinewood derby track that uses USB to communicate between a computer at the track start and an arduino at the finish line 32 feet away.

I found USB to Ethernet adapters at monoprice that I used that successfully for the past 5 years. I think it was something like these - https://www.monoprice.com/product?p_id=6042, but it’s been so long I don’t recall the exact model.

We had a related issue with a USB webcam.
It worked great until we hooked it up to a extra long USB cord.
We wound up getting a special powered USB extension cord. It was a 25’ USB cord with a build in USB powered repeater. That fixed the signal drop out issues we were having.

I am not sure how that would work with an XC. Power issues to the controller might still require a powered hub controller side. And the longer the cable the more susceptible it is to RF noise from the spindle. But it might be worth looking into.