KERN & SOHN TN 60-0.01EE - Manual (Page 10)

10 TN_EE-BA-e-1410
7) Press the key again. The M/S (or IN/
μS) symbols should begin flashing. The
gauge is now displaying the sound velocity value it has calculated based on the
thickness value that was entered.
8) Press the key once again to exit the calibration mode and return to the meas-
urement mode. The gauge is now ready to perform measurements.
4.4.2 Calibration to a known velocity
Note: This procedure requires that the operator knows the sound velocity of the ma-
terial to be measured. A table of common materials and their sound velocities can be
found in Appendix B of this manual.
1) Press the key to activate the calibration mode. The MM (or IN) symbol should
begin flashing.
2) Press the key again, so that The M/S (or IN/
μS) symbols are flashing.
3) Use the key and the key to adjust the sound velocity value up or down, until
it matches the sound velocity of the material to be measured. You can also press
the
key to switch among the preset commonly using velocities.
4) Press the key to exit from the calibration mode. The gauge is now ready to
perform measurements.
To achieve the most accurate measurements possible, it is generally advisable to
always calibrate the gauge to a sample piece of known thickness. Material composi-
tion (and thus, its sound velocity) sometimes varies from lot to lot and from manufac-
turer to manufacturer. Calibration to a sample of known thickness will ensure that the
gauge is set as closely as possible to the sound velocity of the material to be meas-
ured.
4.4.3 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) Probe-Zero has to be performed first.
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 cou-
pling status indicator should appear steadily.
4) Having achieved a stable reading, remove the transducer. If the displayed thick-
ness changes from the value shown while the transducer was coupled, repeat
step 3.
5) Press the key. The MM (or IN) symbol should begin flashing.
6) Use the
key and the key to adjust the displayed thickness up or down, until
it matches the thickness of the sample piece.
7) Press the key. The display will flash 1OF2. Repeat steps 3 through 6 on the
second calibration point.
8) Press the key, so that The M/S (or IN/
μS) symbols are flashing. The gauge will
now display the sound velocity value it has calculated based on the thickness val-
ues that were entered in step 6.
9) Press the key once more to exit the calibration mode. The gauge is now ready
to perform measurements within this range.