1

Is there a maximum length that a USB cable can be?

I want to know if there is an upper limit to its length before it becomes unreliable or useless. If there was also a way to get around this max limit that would be helpful too.

random
  • 450
  • 1
  • 9
  • 16
Eduardo Molteni
  • 753
  • 1
  • 8
  • 17

4 Answers4

9

From http://en.wikipedia.org/wiki/Universal_Serial_Bus#Maximum_useful_distance -

5 meters for USB2.

If you need to go further you can put a hub in the middle, but many devices have trouble if the distance gets too long.

Joel Spolsky
  • 3,686
  • 4
  • 21
  • 19
Matt Simmons
  • 20,218
  • 10
  • 67
  • 114
2

You can get an USB to ethernet extender, that can extend your connection a much further distance. For example:

http://www.iogear.com/product/GUCE51/

We are using this product to extend a USB connection about 25 feet.

Jeff Miles
  • 2,020
  • 2
  • 19
  • 26
1

There are also "active" extension cables that are a 5 meter cable with a 1 port hub built into the far end.

I've heard as many as 5 can be chained together to go farther. Latency starts to become an issue, and many USB drivers do not handle the distance well. It works well enough for remote keyboards and mice.

mfarver
  • 2,576
  • 13
  • 16
1

Had USB running at 6m & 8m, so it will go a bit above the spec, but that was "only" a keyboard/mouse. Used this with lengthy VGA cables on an expo stand.

Not tried any of the "USB-over-cat5" kit yet.. but I kinda fancy it - would stop the stand contractor putting the cables in backwards at least!

Tom Newton
  • 4,021
  • 2
  • 23
  • 28
  • and how did you get cables this long? Only 5mts cables are on sale on Amazon – Eduardo Molteni Jun 03 '09 at 12:19
  • This sounds like it should be the punchline for a bad joke... but "join 2 together"? :) Just used 2 consecutive extenders (plus the length of keyboard cable it may have been up to 9m) – Tom Newton Jun 04 '09 at 07:13