©
National Instruments Corp.
11
NI 9213E Operating Instructions and Specifications
For the best accuracy results, keep temperature gradients across
NI 9213E terminals to a minimum and enable the autozero
channel. Refer to the
and
sections for more information.
Cold-Junction Temperature Measurement Accuracy
Heat dissipated by adjacent modules or other nearby heat sources
can cause errors in thermocouple measurements by heating up the
NI 9213E terminals to a different temperature than the
cold-junction compensation sensor. The thermal gradient across
the terminals can cause the terminals of different channels to be at
different temperatures, in which case the resulting measurement
creates errors not only in absolute accuracy but also in the relative
accuracy between channels. Refer to the
section for
the cold-junction compensation accuracy specifications. The
thermocouple accuracy specifications include the errors caused by
the thermal gradient across the module terminals. Refer to the
Temperature Measurement Accuracy
section in the
for the thermocouple accuracy specifications. Visit
ni.com/info
and enter
cjcdatascaling
for more information about
isothermal errors and scaling CJC data.
