HP E1411A, Руководство по обслуживанию

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Appendix A
Calculating Multimeter Accuracy
Introduction
This appendix shows how multimeter accuracy, measurement uncertainty,
and test accuracy ratio (TAR) values are defined and calculated for the
performance verification tests for the HP E1411 multimeter.
See Table 4-1, "Performance Test Record for the HP E1411 Multimeter" for
90-day specification values of multimeter accuracy, measurement
uncertainty, and test accuracy ratios (TARs).
NOTE
Multimeter accuracy, measurement uncertainty, and test accuracy ratios in
Table 4-1 are valid ONLY for the specified test conditions and assumptions
described in this manual. For the test conditions described, all TARs exceed
the 4:1 requirement of MIL-STD-45662A.
Multimeter Accuracy
Definition
Multimeter accuracy is the expected accuracy of the measurement due
ONLY to the multimeter. The "Low Limit" entry in Table 4-1 is the lower
(-) value of multimeter accuracy, while the "High Limit" entry is the upper
(+) value of multimeter accuracy.
Measurement
Uncertainty Definition
Measurement Uncertainty is the expected accuracy of the source used to
input signals to the multimeter. Since the Datron 4708 Autocal
Multifunction Standard is the source used for measurements in this manual,
the measurement uncertainty of the source is that of the Datron 4708.
This value is shown in the "Measurement Uncertainty" column of Table
4-1. See the Datron 4708 User’s Handbook for additional information on
calculating measurement uncertainty for the Datron 4708 source.
NOTE
Measurement Uncertainty does not apply to the DC Voltage (Zero Volts
Input) test, since no input is applied.
Appendix A Calculating Multimeter Accuracy 65