Appendix A
Specifications
©
National Instruments Corporation
A-3
DAQMeter DAQCard-4050 User Manual
Crest factor errors
Noise Rejection
AC CMRR ..........................................>90 dB, 60 Hz
Input Characteristics
Bandwidth ..........................................20 Hz–25 kHz
Input resistance ...................................1 M
Ω
Resistance
Accuracy
Crest Factor
Additional Error
(% of full scale)
1–2
no error
2–5
1%
5–10
2%
Range
Accuracy
±(% of r
% of range)
Temperature
Coefficient
±(ppm of r
ppm of range)/°C
Overrange
Test
Current
200.000
Ω
0.007% + 0.2%
13 ppm + 175 ppm
200.000
Ω
100 µA
2.00000 k
Ω
0.007% + 0.03%
13 ppm + 20 ppm
2.00000 k
Ω
100 µA
20.0000 k
Ω
0.007% + 0.02%
13 ppm + 3 ppm
20.0000 k
Ω
100 µA
200.000 k
Ω
0.01% + 0.03%
17 ppm + 20 ppm
200.000 k
Ω
1 µA
2.00000 M
Ω
0.01% + 0.06%
17 ppm + 3 ppm
2.00000 M
Ω
1 µA
Extended
Ohms
0.05% + 0.006%*
500 ppm + 30 ppm
n/a
1 µA
*The accuracy of measurements made in the Extended Ohms range varies with the value being
measured. For resistances up to 1 M
Ω
, the accuracy is 0.05%. For resistances between 1 M
Ω
and 20 M
Ω
, the accuracy is 0.1%. For larger resistances, the error is 0.4%.
