TN_EE-BA-e-2020
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material sound velocity" and will certainly not be the same as the actual material to be
measured.
4.4.1 Calibration with known material thickness
Note: This procedure requires a sample of the material to be measured, its exact
thickness, which has been measured in some way before.
1. The zero setting is made.
2. The sample material is provided with coupling gel.
3. The US measuring probe is pressed onto the piece of material, making sure
that it lies flat on the surface. A material thickness value is now shown on the
display and the coupling symbol should appear.
4. As soon as a stable reading value is reached, the US measuring probe is lifted
off again. If the thickness of the material just detected differs from the value
that existed during the coupling, step 3) must be repeated.
5. The key is pressed and thus the calibration mode is activated. The MM (or
IN) symbol should start flashing.
6. With the and keys you
can now adjust the required material thickness (that
of the material pattern).
7. The key is pressed again and the M/S (or IN/ µS) should start flashing. The
display will now show the sound velocity value previously calculated based on
the material thickness.
8. To exit the calibration mode, press the key to return to the measuring mode.
From now on measurements can be made.
4.4.2 Calibration at known sound velocity
Note: For this procedure the sound velocity of the material to be measured must be
known.
1. Press the key to activate the calibration mode. The MM (or IN) symbol
should start flashing.
2. Press this button repeatedly so that the M/S (or IN/ µS) symbol also flashes.
3. Use the and
keys to change
the sound velocity value up or down until it
corresponds to the sound velocity of the material to be measured. It is also
possible to switch between the preset, generally used velocities of sound with
the key.
4. To exit the calibration mode, press the key. From now on measurements can
be made.
In order to obtain the most accurate measurement result possible, it is generally
recommended to calibrate the measuring instrument with a material sample of known
material thickness.
The material composition itself (and thus the speed of sound) often varies from one
manufacturer to another. Calibration with a material sample of known thickness
ensures that the instrument is adjusted as accurately as possible to the material to be
measured.
