National Instruments NI 9219 - Manual (Page 18)

NI 9219 Operating Instructions 18 ni.com
environment and avoid placing heat sources near the module
or its connectors. Refer to the
Specifications section for more
information about accuracy. The NI 9219 does not support open
thermocouple detection. Refer to Figure 11 for an illustration of
the connections.
Figure 11. Connections in Thermocouple Mode
Digital In Mode
Digital In mode has a 60 V unipolar threshold that you can set in
software. Refer to the software documentation for information
about setting this threshold. Digital In mode is supported only in
CompactRIO systems. Refer to Figure 6 for an illustration of the
connections.
Open Contact Mode
Open Contact mode sources a current between the HI and LO
terminals and determines if the two terminals are open or closed
based on the measured current through the terminals. When the
HI
LO
TC ADC
NI 9219
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