Analog input dc voltage measurement accuracy – Measurement Computing USB-2408 Series User Manual
Page 23
USB-2408 Series User's Guide
Specifications
23
Table 4. Thermocouple accuracy specifications, including CJC measurement error.
All specifications are (±).
Thermocouple
Sensor temperature
range
Accuracy error,
maximum
Accuracy error,
typical
Tempco
(°C/°C)
J
–210 °C
2.572 °C
1.416 °C
0.022
0 °C
0.935 °C
0.469 °C
1200 °C
1.869 °C
1.456 °C
K
–210 °C
2.917 °C
1.699 °C
0.029
0 °C
1.017 °C
0.526 °C
1372 °C
2.478 °C
2.022 °C
N
–200 °C
3.480°C
2.030 °C
0.029
0 °C
1.201 °C
0.659 °C
1300 °C
1.991 °C
1.600 °C
R
–50 °C
4.826 °C
3.133 °C
0.082
250 °C
2.117 °C
1.424 °C
1768 °C
2.842 °C
2.347 °C
S
–50 °C
4.510 °C
2.930 °Co
.089
250 °C
2.165 °C
1.468 °C
1768 °C
3.187 °C
2.597 °C
B
250 °C
5.489 °C
3.956 °C
0.14
700 °C
2.283 °C
1.743 °C
1820 °C
2.202 °C
1.842 °C
E
–200 °C
2.413 °C
1.352 °C
0.017
0 °C
1.069 °C
0.551 °C
1000 °C
1.575 °C
1.211 °C
T
–200 °C
2.821 °C
1.676 °C
0.027
0 °C
1.050 °C
0.558 °C
400 °C
0.957 °C
0.595 °C
To achieve the thermocouple accuracies listed above, warm up the USB-2408 Series device for 45 minutes after
the initial power on. The accuracies listed above are only guaranteed if the device is housed in the plastic
enclosure.
Analog input DC voltage measurement accuracy
Table 5. DC Accuracy components and specifications. All values are (±)
Range
Gain error (%
of reading)
Offset
error
INL error (%
of range)
Absolute
accuracy
Gain temperature
coefficient
(% reading/°C)
Offset
temperature
coefficient
(µV/°C)
±10 V
0.0037
50 µV
0.0008
500 µV
0.0006
3
±5 V
0.0047
25 µV
0.0008
300 µV
0.0006
2
±2.5 V
0.0059
20 µV
0.0008
200 µV
0.0006
1
±1.25 V
0.0056
20 µV
0.0008
100 µV
0.0006
1
±0.625 V
0.0068
15 µV
0.0005
60 µV
0.0006
1
±0.3125 V
0.0104
15 µV
0.0006
50 µV
0.0006
1
±0.15625 V
0.0184
10 µV
0.0005
40 µV
0.0006
1
±0.078125 V
0.0384
10 µV
0.0009
40 µV
0.0006
1