ELECTRICAL MEASUREMENT TERMINOLOGIES

MEASUREMENT:

The set of operations having the object of determining the value of a quantity.

MEASURAND:

A quantity subject to measurement.

METROLOGY:

The field of knowledge concerned with measurement. This term covers all aspects both theoretical and practical with reference to measurement, whatever their level of accuracy, and in whatever field of science or technology they occur.

ACCURACY:

The closeness of agreement between the result of a measurement and the true value of the measurand.

SYSTEMATIC ERROR:

A component of the error of measurement which, in the course of a number of measurements of the same measurand, remains constant or varies in a predictable way.

CORRECTION:

The value which, added algebraically to the uncorrected result of a measurement, compensates for an assumed systematic error.

RANDOM ERROR:

A component of the error of measurement which, in the course of a number of measurements of the same measurand, varies in an unpredictable way.

UNCERTAINTY OF MEASUREMENT:

An estimate characterizing the range of values within which the true value of a measurand lies.

DISCRIMINATION:

The ability of a measuring instrument to respond to small changes in the value of the stimulus.

TRACEABILITY:

The property of the result of a measurement Where by it can be related to appropriate standards, generally international or national standards, through an unbroken chain of comparisons.

CALIBRATION:

The set of operations which establish, under specified conditions, the relationship between values indicated by a measuring instrument or measuring system and the corresponding known value of a measurand.

ADJUSTMENT:

The operation intended to bring a measuring instrument into a state of performance and freedom from bias suitable for its use.

INFLUENCE QUANTITY:

A quantity which is not the subject of the measurement but which influences the value of a measurand or the indication of the measuring instrument.

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PRIMARY SECONDARY AND TERTIARY FREQUENCY CONTROL IN POWER SYSTEMS

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