©
National Instruments Corporation
11
USB-9211/9211A User Guide and Specifications
Measurement Accuracy for the Different Types
of Thermocouples
Figures 9, 10, 11, 12, and 13 show the typical and maximum errors for the
different thermocouple types when used with the USB-9211/9211A over
the full temperature range. The figures also show the maximum error for
the thermocouple types with the USB-9211/9211A at room temperature,
15 to 35 °C. The figures account for gain errors, offset errors, differential
and integral nonlinearity, quantization errors, noise errors, and isothermal
errors. The figures do
not
account for the accuracy of the thermocouple
itself.
Temperature gradients across the USB-9211/9211A terminals affect the
cold-junction temperature accuracy. Refer to the
Temperature Measurement Accuracy
section for more information about
temperature gradients.
Figure 9.
Type B Errors
200
400
600
800
1200
1600
1800
0
2
4
6
Max over Temp Range with Autozero
Max at Room Temp Range without Autozero
Typ over Temp Range with Autozero
Error (
°
C)
1000
1400
Measured Temperature (
°
C)