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Oleg
Premium
join:2003-12-08
Birmingham, AL
kudos:2

1 edit

People complain about USB cable length

I have seen review on Newegg, saying USB cable is too shot for the portable external HDs. I mean come on now. Just buy "3 ft. or "6 ft. USB cable, and the problem is solved!



koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23

This is generally bad advice if the device being used is a hard disk (and possibly other high-power-draw devices).

The people who complain about cable length do not understand the nature of the situation. But much of the fault also falls on the vendors/manufacturers for not being completely up front and disclosing why the cables are short and why that's extremely important. Third paragraph here hints at the answer.

With USB 3.0 this is less of a concern as the maximum current has been increased to 900mA for a single port, while for USB 2.0 and earlier this is limited to 500mA.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.



Oleg
Premium
join:2003-12-08
Birmingham, AL
kudos:2

Maybe i misunderstood something. Are you saying If the cable is longer or too long it can have an effect on lifespan of the device or decrease the performance?


HarryH3

join:2005-02-21
kudos:1
Reviews:
·Suddenlink

2 recommendations

It all has to do with Ohms law. The longer cable has higher resistance. Portable drives rely on ONLY the USB cable for both data and POWER. The higher resistance of a longer cable can create just enough voltage drop to prevent the drive from spinning up. It isn't a problem with non-portable drives because they use an external power supply for the drive and the USB cable is only passing data.



craig70130
Premium
join:2004-04-27
New Orleans, LA
reply to Oleg

The review was probably referring to an external drive with a hard-wired cable and for most of those drives, the cable length is a foot or less like the many I've purchased.



Oleg
Premium
join:2003-12-08
Birmingham, AL
kudos:2

1 edit

Personally i never have had an issue with length of USB cables. Even with USB 2.0 cables. I have a probable external, and i am not experiencing any issues using "6 ft. USB 3.0 cable.



craig70130
Premium
join:2004-04-27
New Orleans, LA

said by Oleg:

Personally i never have had an issue with length of USB cables. Even with USB 2.0 cables. I have a probable external, and i am not experiencing any issues using "6 ft. USB 3.0 cable.

Like I mentioned above, I believe the review you read was referring to hard-wired USB cables on the device you were viewing - those typically are very short.


Oleg
Premium
join:2003-12-08
Birmingham, AL
kudos:2

Yes. I was talking about those. This is why i have gotten my self 6ft. USB 3.0 cable.


dave
Premium,MVM
join:2000-05-04
not in ohio
kudos:8
Reviews:
·Verizon FiOS
reply to craig70130

said by craig70130:

The review was probably referring to an external drive with a hard-wired cable (...)

As in, the cable is permanently attached at the drive end?

Ugh, I have never run into one of those. It's something to watch out for, I guess.


Oleg
Premium
join:2003-12-08
Birmingham, AL
kudos:2
reply to craig70130

I was talking about those »www.newegg.com/Product/Product.a···22236519



koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23

said by Oleg:

I was talking about those »www.newegg.com/Product/Product.a···22236519

The product linked has a fully 100% removable USB cable, and is USB-bus-powered (not AC-powered). I cannot tell if it houses a 2.5" or 3.5" drive but my guess is a 2.5" drive (yes it matters; 3.5" drives require more power to spin up, and are almost always AC-powered).

The sole fact it's USB 3.0 may provide the ability to use longer cables without a substantial voltage drop, but I sure as hell would not trust a 6 foot USB 3.0 cable with such a device. Two feet maybe, but it's pointless to discuss. You're supposed to use the USB cable provided with the product.

The comments I have made about cable length, with the full technical explanation provided by HarryH3 See Profile, still stand. If you don't understand what we've said, just say so and we can try to explain it in even more simple terms.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.