Actually "extension cords" violate the USB spec. That is because they allow= =20 an unlimited cable length, and USB is guaranteed only to 15 feet. Of course= =20 in this power-only application they should be no trouble. However, you migh= t=20 find anything longer than about 15 feet very difficult to find. -- Bob Ammerman RAm Systems ----- Original Message -----=20 From: "Adam Field" To: "Microcontroller discussion list - Public." Sent: Monday, December 05, 2011 9:21 PM Subject: Re: [EE] LONG USB Power Cable > On Dec 5, 2011 8:19 PM, "Harold Hallikainen" =20 > wrote: >> >> To take advantage of low cost USB style power supplies, I did a product >> that uses an USB mini B connector as the power input. No data goes acros= s >> the USB bus. I can find low cost A to mini-B cables out to about 10 feet= .. >> But, of course, I have a customer that wants to put the wall mount power >> supply 30 feet away. He doesn't like stringing USB extension cords. So..= .. >> Anyone know of a 30 foot USB power cable (no data lines required, just >> ground and +5VDC with an A connector at one end and a mini-B at the >> other)? >> > Check monoprice.com. They have at least 15ft. They also have active > extensions. > --=20 > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist=20 --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .