USB 2 Maximum Cable Length

Discussion in 'General Hardware' started by zazal, Nov 19, 2007.

  1. zazal

    zazal OSNN One Post Wonder

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    My backup device is a USB 2.0 250 MB Iomega Hard Drive.I'd like to put
    it in my garage, requiring about 20 to 25 feet of wire. The official
    USB specs say 5 meters max; if further use a hub/repeater.

    I'm wondering how realistic the 5 meter spec is. I recall that parallel
    printer cables were supposed to be limited to 10 feet or so; 75 foot
    cables worked just fine. Same thing with the specs for RS-232 cables.

    Does anyone have any real world experience with long USB 2.0 cables?
    I'm thinking of building mine using unshielded CAT5 cable, one twisted
    pair for power, another for data. Wise? foolish?
     
    Last edited by a moderator: Nov 19, 2007
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  2. fitz

    fitz Just Floating Along Staff Member Political User Folding Team

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    personally, I wouldn't do it. As it's your backup device, would you want to risk data loss and/or data corruption caused by signal degradation onto a backup device?

    A printer is one thing to try to stretch the distance limit.. a Hard drive and backup data is entirely different.

    Go buy a USB hub, put it somewhere in between and get two 5m cables.

    http://www.usb.org/developers/usbfaq/#cab1
     
  3. zeke_mo

    zeke_mo (value not set) Staff Member Political User Folding Team

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    250MB? Might be time to upgrade
     
  4. gonaads

    gonaads Beware the G-Man Political User Folding Team

    Don't push the limit when it comes to cable length specs. These are set so you don't get data corruption. It's better to use a hub/repeater and be totally safe especially if you data is important.

    Now my curiosity is getting the better of me. Why do you want to put the backup drive in your garage so far away? External drives are small and take up little room/space. Why not have it close by?
     
  5. Shamus MacNoob

    Shamus MacNoob Moderator Political User

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    Just add another hard drive to the machine they cost nothing now.
     
  6. Tuffgong4

    Tuffgong4 The Donger Need Food!!!! Political User

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    is it a temperature thing??? do you want the hard drive to stay cool?

    either way when it's data or even sensitive data the shorter the cable the better.

    Also if you've just purchased the backup drive see if you can buy an external hard drive with networking instead, (NAS)
     
  7. LeeJend

    LeeJend Moderator

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    You don't put computer equipment in a garage, regardless of cable length. Heat, cold, humidity, dust, roaches, ants and other vermin crawling around inside of it will trash the device.
     
  8. X-Istence

    X-Istence * Political User

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    I absolutely agree. I used to have a machine I kept downstairs in the basement, and when I finally had to move it with me to Arizona, I took the case apart after it having been online for a good year and a half and it was FILLED with dust. I was surprised the fans even kept moving in that thing (good thing they did :p).

    Took a good hour to vacuum it out, and get all the dust out of the heatsink.
     
  9. Shamus MacNoob

    Shamus MacNoob Moderator Political User

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    Another one post wonder who will not come back to thank us?

    :laugh::laugh::laugh:
     
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  10. Bman

    Bman OSNN Veteran Original

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    Yea, MB? was that correct, thats not that usefull as a backup. :eek:
     
  11. Heeter

    Heeter Overclocked Like A Mother

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    Hmmm,

    I have a printer on a custom made 50 foot USB cable. It's no HD, but I haven't had any problems with it. Maybe printers are easier on data transfer than Hd's.


    Heeter