Fluke 5790A Service Manual page 330

5790A
Service Manual
Settling Time
The time taken for a measurement device's reading to stabilize after a voltage is applied
to the input.
Shield
A grounded covering device designed to protect a circuit or cable from electromagnetic
interference. Also see "guard".
SI System of Units
The cepted International System of Units. See also "units", "base units", and "derived
units".
Specifications
A precise statement of the performance of a measurement or stimulus device.
Square Law
Defines the response of a device whose output is proportional to the square of the applied
stimulus. Thermocouple-type transfer devices have a square-law response.
Stability
A measure of the freedom from drift relative to a reference value, over time and over
changes in other variables such as temperature. Note that stability is not the same as
uncertainty.
Standard
A device that is used as an ext value for reference and comparison.
Standard Cell
A primary cell that serves as a standard of voltage. The term "standard cell" often refers
to a "Weston normal cell", which is a wet cell with a mercury anode, a cadmium mercury
amalgam cathode, and a cadmium sulfate solution as the electrolyte.
Systematic Error
Any error that remains constant or varies in a predictable manner as successive
measurements of the same quantity are made under effectively identical conditions. Note
that a known systematic error can be compensated for with a correction, whereas, a
random error cannot. Also see "random error".
Temperature Coefficient
A ftor used to calculate the change in indication or output of an instrument as a result of
changes in temperature. Changes in temperature contribute to instrument uncertainty by
an amount determined by the temperature coefficient.
Test Uncertainty Ratio
The numerical ratio of the uncertainty of the measurement system or device being
calibrated or verified, and the uncertainty of the measurement system or reference device.
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