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National Instruments Corporation
19
NI USB-9211/9211A User Guide and Specifications
Specifications
The following specifications are typical at 25 °C, unless otherwise noted.
All voltages are relative to COM unless otherwise noted.
Input Characteristics
Number of channels ............................... 4 thermocouple channels,
1 internal autozero channel,
1 internal cold-junction
compensation channel
ADC resolution ...................................... 24 bits
Type of ADC.......................................... Delta-sigma
Input range ............................................. ±80 mV (not software selectable)
Common-mode range
Channel-to-COM ............................ ±1.5 V
Common-to-earth ground ............... ±250 V
Common-mode rejection ratio (0 to 60 Hz)
Channel-to-common ....................... 95 dB
Common-to-earth ground ...............
>
170 dB
Temperature measurement ranges ......... Works over temperature
ranges defined by NIST
(J, K, R, S, T, N, E, and
B thermocouple types)
Cold-junction compensation sensor accuracy
0 to 60 °C ........................................ 0.6 °C (1.1 °F) typ,
1.3 °C (2.3 °F) max
Conversion time ..................................... 70 ms per channel;
420 ms total for all channels
including the autozero and
cold-junction channels
