Whats the maxium length of a USB cable?

[Fisher]

Is there a maxium length of a USB cable? does the lenght of the cbale have any affect of latency or quality of signal from and to the device? does the device have any affect on how the cable can be?

EDIT: the device im thinking in particular is a web cam

 

[MikeReiner]

I believe so yes. I'm not certain.. I recall after about 15 FT you must get a power conduit of some sort to keep the power level up over the distance.. but don't quote me on this.

 

[LambOfGod]

the USB specification limits the length of a cable between full speed devices to 5 meters (a little under 16 feet 5 inches).

For a low speed device the limit is 3 meters (9 feet 10 inches).

hope that helps

 

[Fisher]

so how would you increase the length of the USB cable? as Mike reiner suggested by using a power conduit? but how does a pwoer conduit work and where can i get one from (UK)?