National Instruments NI 9476 - Manual (Page 11)

© National Instruments Corp. 11 NI 9476 Operating Instructions and Specifications
I/O Protection
The NI 9476 is protected against overcurrent, inrush, and
short-circuit conditions in accordance with IEC 1131-2.
Understanding Protected Devices
Each channel on the NI 9476 has circuitry that protects it from
voltage and current surges resulting from short circuits.
Caution The NI 9476 can be damaged under overvoltage
and reverse bias voltage conditions. Check the voltage
specifications for all devices that you connect to the
NI 9476.
Excessive current through a DO pin causes the channel to go into
an overcurrent state. In an overcurrent state, the channel cycles off
and on until the short circuit is removed or the current returns to an
acceptably low level. Refer the
Specifications section for typical
trip currents.
Each channel has a status line that indicates in software whether the
channel is in an overcurrent state. Refer to the software help for
information about reading output status.