NOTE:
Be sure that a probe zero has been performed prior to performing this
calibration procedure.
1. Physically measure an exact sample of the material, or a location directly on the
material to be measured, using a set of calipers or a digital micrometer.
2. Apply a drop of couplant on the transducer and place the transducer in steady
contact with the sample or actual test material. Be sure that the reading is stable and
the repeatability indicator, in the top left corner of the display, is fully lit and stable.
3. Press the
key to enter the calibration edit screen displaying the current
velocity IN /μs (M /s) value. The edit icon will be illuminated and
flashing.
4. Press the
key again to edit the known thickness value. The edit icon will be
illuminated and flashing and the units will be IN or MM,
indicating thickness.
5. Use the
and
keys to scroll to the known thickness value.
NOTE:
The longer the keys are pressed and held, the faster the value will increment/
decrement.
NOTE:
Pressing the
key prior to pressing the
key will abort to the
measurement screen without saving changes.
6. Once the known thickness value is being displayed, press the
key to return
to the measurement screen and display the calculated material velocity.
NOTE:
The known thickness value that was used to calibrate will be displayed in the
top right corner of the display for confirmation.
7.3 Calibration to a known velocity
The velocity can also be directly edited and set to a target velocity value that was
previously determined from a reference standard at an earlier time.
The procedure for directly entering the velocity is outlined below:
NOTE:
Be sure that a probe zero has been performed prior to performing this
calibration procedure.
NOTE:
This procedure requires that the operator know the sound-velocity of the
material to be measured. A table of common materials and their sound-velocities can be
found in Appendix A.
1. Apply a drop of couplant on the transducer and place the transducer in steady
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