Fluke 5790A, Руководство оператора

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A-1
Appendix A
Glossary of AC-DC Transfer Related Terms
absolute uncertainty
Uncertainty that includes contributions from all sources, i.e., traceability to national
standards of the standards used, plus the uncertainty of the measurement process.
Absolute uncertainty should be used to compute test uncertainty ratio. Also see "relative
uncertainty".
accuracy
The degree to which the measured value of a quantity agrees with the accepted,
consensus, or true value of that quantity. Accuracy is the same as 1 - % uncertainty. For
example, an instrument specified to +/-1% uncertainty is 99% accurate. Also see
"uncertainty".
artifact calibration
An instrument calibration technique that uses a calibration system within the instrument
to reduce the number of required external standards to a small number of artifact
standards. The Fluke 5700A Calibrator uses Artifact Calibration.
artifact standard
A stable object that produces or embodies a physical quantity for use as a reference
standard. An artifact standard may have an assigned traceable value when used for
calibration purposes. Fluke 732A DC Voltage Reference Standard and the Fluke 742A
Series Standard Resistors are examples. Also see "transfer standard".
ac-dc absolute uncertainty
Includes all known error sources contributing to the uncertainty of an ac-dc difference
correction. This includes NIST (National Institute of Standards and Technology)
uncertainties, transfer uncertainty from a primary standard to a working standard, and
internal error contributions (both random and temperature related).
ac-dc transfer
The process of comparing an ac voltage to a known dc voltage, thereby transferring the
low uncertainty of the dc voltage to the ac voltage. The 792A can be used to perform two
different types of ac-dc transfers: