© PCE Instruments
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5.15
Measurement Accuracy
Factors of affecting measurement accuracy, please reference the chapter 6 Factors Affecting
Measurement Accuracy. Under normal use and careful calibration, all subsequent
measurements will lie within the guaranteed measuring tolerance. When using the statistics
programmer for obtaining a mean value it is advisable to place the probe several times at a
typical measuring spot or at fixed measuring spot.
Any false readings or outliers can be deleted immediately. The final reading derives from the
statistical calculation and from the guaranteed tolerance levels of the gauge.
T(coating thickness)=M(mean value)±S(standard deviation)±A(measuring accuracy).
6
Factors Affecting Measurement Accuracy
User needs to know the factors of affecting measurement accuracy before using the gauge.
The factors are listed below.
Factors Principle
Magnetic Eddy Current Recommendations
Magnetic properties
√
Need to calibrate
Electrical properties
√
Need to calibrate
Curvature radius
√
√
See specifications and calibrate
Substrate thickness
√
√
See specifications and calibrate
Size of measuring area
√
√
See specifications and calibrate
Surface roughness
√
√
Position and shape
√
√
Sample deformed
√
√
Avoid to measure on too soft or too thin
material
Adhesive substances
√
√
Clean probe and sample
Strong magnetic field
√
Be away from strong magnetic field
Temperature
and
humidity
√
√
Recalibrate at the same environment
conditions
Measuring operations
√
√
Read the chapter 5.2 Basic Measurement Step
Low battery
√
√
Replace the battery
Probe wear
√
√
Contact PCE Instruments