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2.7 - +5V

The LabJack has a nominal +5 volt internal power supply. Power can be drawn from this power supply by connecting to the +5V screw-terminals, or the +5V pins on the DB25 connector. The total amount of current that can be drawn from the +5V pins, analog outputs, and digital outputs, is 450 mA for most desktop computers and self-powered USB hubs. Some notebook computers and bus-powered hubs will limit this available current to about 50 mA.

The USB specification requires all hosts and hubs to have overcurrent protection. If the user puts too large a load on +5V (including a short circuit of +5V to GND) of the LabJack U12 (a USB device), the host or hub is responsible for limiting the current.