Understanding The Usb2Xchange Power Supply - Adaptec USB2Xchange User Manual

Understanding the
USB2Xchange Power Supply
The USB2Xchange adapter receives its electrical power from the
termination power line of attached SCSI devices. If this power
supply is not available, the adapter switches automatically to
receive power from the USB bus.
There are cases when the USB bus cannot supply the needed power
for the USB2Xchange to operate—if, for example, you're using an
unpowered USB hub and the attached SCSI devices don't supply
SCSI termination power. In these cases, you may need to use an
optional DC power supply.
Note: Adaptec strongly recommends that you plug the
USB2Xchange directly into a USB port on your computer. If
you must connect through a USB hub, use only a self-
powered USB hub.
You receive an error message (like the one shown below) if the
USB2Xchange is not supplied with enough power to operate.

Understanding the USB2Xchange Power Supply

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