Fluke 5790B, Руководство по обслуживанию

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Appendices
Glossary of AC-DC Transfer Related Terms
A
A-7
Reliability
A measure of the probability of failure of an instrument.
Repeatability
See “precision”.
Resistance
A property of a conductor that determines the amount of current that will flow
when a given amount of voltage exists across the conductor. Resistance is
measured in ohms. One ohm is the resistance through which one volt of the
potential will cause one ampere of current to flow.
Resolution
The smallest change in quantity that can be detected by a measurement system
or device. For a given parameter, resolution is the smallest increment that can be
measured, generated or displayed.
Reversal Error
Also called turnover error, the difference in output of an AC-DC transfer standard
for the same DC input but with polarity reversed. The output logged for the DC
reference should be the average of the two readings.
RF (Radio Frequency)
The frequency range of radio waves; from 150 kHz up to the infrared range.
RMS (Root-Mean-Square)
The value assigned to a voltage or current that results in the same power
dissipation in a resistance as a DC current or voltage of the same value.
RMS Sensor
A device that generates a DC output signal proportional to the RMS value of the
input signal. RMS sensors operate by measuring the heat generated by a voltage
through a known resistance (for example, power); therefore, they sense true
RMS voltage. RMS sensors are used to make AC-DC difference measurements.
Scale
The absolute span of the reading range of a measurement device including
overrange capability.
Scale Error
See “gain error”.
Secondary Standard
A standard maintained by comparison against a primary standard.