The area of variation between upper and lower limits on a particular scale.
Measurement Range
The measured range is within a precisely defined range in which defined agreed, or guaranteed error limits are not exceeded.
Lower limit value of measuring range
The minimum value to be measured within the exact specified range
Upper limit of measurement range
The maximum value to be measured within the exact specified range
Performance Features
Parameters related to the functions and capabilities of level measuring instruments and their quantitative expression
Reference performance characteristics
Performance characteristics achieved at reference operating conditions
Scale
An ordered set of markers and all relevant numbers
Scale range
The range bounded by the beginning and end values of the scale
Linear scale
The spacing of each compartment in the scale is in constant proportion to the corresponding compartment value
Non-linear scale
The spacing of each scale division in the scale is non-numerically proportional to the corresponding division value
Suppression of zero scale
In the scale range, the scale value corresponding to the measured zero value is not included, such as the Scale of a medical thermometer
Extended Scale
In the scale range, disproportionate extensions account for most of the scale length
Scale Numbers
The whole set of numbers marked on the scale corresponds to the measured value identified by the scale mark, or only the numerical order of the scale mark
Scale Marking
Scale lines or other marks indicating the measured value on the device
Scale compartment
The scale value between two adjacent scale marks
Scale compartment value
The difference between the measured values of two adjacent scale marks in the scale is also called the grid value.
Scale divider spacing
The distance between the centerlines of any two adjacent scale marks measured along the same line segment represents the length of the scale
Scale Length
The length of the line segment passing through the midpoint of all shortest marks on a given scale between the beginning and end scale marks, either as a real or imaginary curve or line
Scale Start Point Value
The measured value corresponding to the scale start point mark
Scale end point value
The measured value corresponding to the scale end mark
Zero Mark
Also called the zero scale line, the indicator has a “0” number scale mark
Zero position of level measuring instrument
When any auxiliary energy required for the operation of the level measuring instrument is turned on and the measured value is zero, the direct indicated value of the instrument
Instrument constants
In order to obtain the indicated value of the instrument, a factor must be multiplied by the direct indicated value. If the direct value is equal to the measured value, the constant of the measuring instrumentation is 1
Calibration
The operation to establish the relationship between the indicated value of a measuring instrument or measuring system or the value embodied in a physical gauge and the known value corresponding to the measured under specified conditions
Calibration Curve
A curve that represents the relationship between the measured value and the actual measured value of the instrument under specified conditions
Standard cycle
Combination of upward and downward calibration curves between instrument calibration range limits
Error Limits
That is, the maximum permissible error, the limit of the instrumentation error specified by the standard technical specifications
Traceability
A characteristic of a measurement result that can be linked to an appropriate standard, (usually an international or national standard) by a continuous chain of comparisons
Sensitivity
The output variation of the meter divided by the corresponding input variation value
Precision
The degree of agreement between the displayed value of the instrument and the measured value