Filter
Top Products
© National Instruments Corporation 15 NI USB-9472 User Guide and Specifications
Power Supplies and Overcurrent Conditions
If a short-circuit occurs, the current through DO can exceed the current
rating for the power supply and the maximum continuous output current for
the NI USB-9472.
If the power supply you are using with the NI USB-9472 cannot supply
more than the guaranteed trip current, the module may be damaged if a
short-circuit condition occurs.
Detecting an Overcurrent Condition
If a device connected to the module is not working while the channel is on,
the module channel may be in an overcurrent state. Neither the software nor
the module LEDs indicate if an overcurrent condition occurs. A channel
LED may be on even though the channel is off because of an overcurrent
condition. To determine if the channel is in an overcurrent state, measure
the voltage between DO and V
sup
. If the voltage is equal to the voltage of
the external power supply connected to the module, the channel is in an
overcurrent state.
Resetting Channels After an Overcurrent Condition
After you have determined and fixed the cause of the overcurrent condition,
reset the channel by turning it off. You can disconnect the external power
supply from the module, however, doing so disconnects power from all of
the module channels. Normal operation can resume after you correct the
overcurrent condition and reset the channel.
Specifications
The following specifications are typical for the range 0 to 60 °C unless
otherwise noted. All voltages are relative to COM unless otherwise noted.
Output Characteristics
Number of channels ............................... 8 digital output channels
Output type............................................. Sourcing
Supply voltage range (V
sup
).................... 6 to 30 V
Output voltage........................................ V
sup
– (I
0
· R
0
)
Output impedance (R
0
)........................... 0.13 Ω max; 0.07 Ω typ
Continuous output current (I
0
) ............... 0.75 A max per channel