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5.4.2 Calibration to a known thickness
Note: This procedure requires a sample piece of the specific material to be measured, the
exact thickness of which is known, e.g. from having been measured by some other means.
1
Perform a Probe-Zero on the standard 4.00 mm disc.
2
Apply couplant to the sample piece.
3
Press the transducer against the sample piece, making sure that the transducer sits flat
against the surface of the sample. The display should show some thickness value, and the
coupling status indicator should appear steadily.
4
Having achieved a stable reading, remove the transducer. If the displayed thickness
changes from the value shown while the transducer was coupled, repeat step 3.
5
Press the
/
key
to enter the “Input Nominal
Thickness” dialog. See right
figure.
6
Press F1/F2 and
/
to input the thickness
value, until it matches the
thickness of the sample
piece.
7
8
Press
/F3 to confirm the input. The gauge exits from the input dialog and return to the
measurement mode. It is now displaying the sound velocity value it has calculated based on the
thickness value that was input.
9
The gauge is now ready to perform measurements.
5.4.3 Two Point Calibration
Note: This procedure requires that the operator has two known thickness points on the test
piece that are representative of the range to be measured.
1
Perform a Probe-Zero on the standard disc.
2
Apply couplant to the sample piece.
3
Press the transducer against the sample piece, at the first/second calibration point,
making sure that the transducer sits flat against the surface of the sample. The display should
show some (probably incorrect) thickness value, and the coupling status indicator should appear
steadily.
4
Having achieved a stable reading, remove the transducer. If the displayed thickness
changes from the value shown while the transducer was coupled, repeat step 3.
5
Press the
/
key to enter the “Input Nominal Thickness” dialog. See right figure.
6
Press F1/F2 and
/
to input the thickness
value, until it matches the
thickness of the sample
piece. Then press
to
calibrate the second point,
see the following figure.
7
8
Figure: Testing the second
point
during
Two
Point