Two words: ground loop. If that's it, then it's an obvious bad design on the part of the APC folks.
Matt On Sat, Nov 10, 2001 at 03:12:10PM -0500, Rob Crittenden wrote: > I've got a Gigabyte TX3 motherboard with 2 built-in USB ports. I ran Windows > on this previously with a USB scanner (HP 3300C). I later turned it into a > Linux router. > > I've burned through 3 APC BK500 UPSs and I've tracked the problem down to > the USB connector. > > Into the first UPS I plugged a bunch of equipment into (way too much) and the > USB connector and smoke started pouring out of the back. I unplugged everything > and APC kindly sent me a new unit. I then plugged in just the PC which > has a 250W power supply and the USB. It again started to burn right away. > Both times the UPS was on a rack so it was difficult to see exactly what was > going on, but the acrid smoke was enough to tell me something was amiss. > > The APC test folks had looked at the first UPS I had returned and they found > a bunch of burned components but they coudln't tell why it failed. I haven't > returned the 2nd unit yet. > > I just got the 3rd unit yesterday and charged the battery. This time I > decided to to a little detective work. First I plugged it into the outlet it > would be powered on (it was charged elsewhere) and everything was a-ok. I then > grabbed the USB cable from the new UPS and plugged it into the PC and > the UPS. I had already loaded the USB and HID drivers into linux > (kernel 2.2.18 with the USB patches). The UPS immediately started to smoke, > and this time it was obviously smoking from the USB/data connector. > > I'll call APC on Monday to see what's going on, but I can't believe that > USB has enough juice to cause the thing to fry, I'm wondering if you guys > have any ideas. > > thanks > > rob > > % lspci -vv > > 00:07.2 USB Controller: Intel Corporation 82371AB PIIX4 USB (rev 01) > Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Step > ping- SERR- FastB2B- > Status: Cap- 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort > - <MAbort- >SERR- <PERR- > Latency: 32 set > Interrupt: pin D routed to IRQ 11 > Region 4: I/O ports at 6400 > > % modprobe usb-uhci > > usb-uhci.c: $Revision: 1.237 $ time 23:24:37 Dec 23 2000 > usb-uhci.c: High bandwidth mode enabled > usb-uhci.c: USB UHCI at I/O 0x6400, IRQ 11 > usb-uhci.c: Detected 2 ports > usb.c: new USB bus registered, assigned bus number 1 > usb.c: USB new device connect, assigned device number 1 > usb.c: kmalloc IF c5fa3840, numif 1 > usb.c: new device strings: Mfr=0, Product=2, SerialNumber=1 > usb.c: USB device number 1 default language ID 0x0 > Product: USB UHCI Root Hub > SerialNumber: 6400 > hub.c: USB hub found > hub.c: 2 ports detected > hub.c: ganged power switching > hub.c: standalone hub > hub.c: global over-current protection > hub.c: power on to power good time: 2ms > hub.c: hub controller current requirement: 0mA > hub.c: port 1 is removable > hub.c: port 2 is removable > hub.c: local power source is good > hub.c: no over-current condition exists > hub.c: enabling power on all ports > usb.c: hub driver claimed interface c5fa3840 > usb.c: kusbd: /sbin/hotplug add 1 > usb.c: kusbd policy returned 0x0 > > > > _______________________________________________ > [EMAIL PROTECTED] > To unsubscribe, use the last form field at: > https://lists.sourceforge.net/lists/listinfo/linux-usb-users -- Matthew Dharm Home: [EMAIL PROTECTED] Maintainer, Linux USB Mass Storage Driver It's monday. It must be monday. -- Greg User Friendly, 5/4/1998
msg01541/pgp00000.pgp
Description: PGP signature
