Olympus 27MG, Руководство пользователя, Страница: 46 / 98

DMTA-10043-01EN, Rev. C, July 2016
Chapter 5 38
5.4.1 When Material Sound Velocity Is Unknown
To perform the material velocity calibration, a calibration block made from the
material to be measured must be used. The block should be approximately as thick as
the thickest section to be measured and have flat, smooth, and parallel front and back
surfaces. The thickness of the block must be known exactly (see Figure 5-2 on
page 38).
Figure 5 ‑ 2 The unknown sound material Do ‑‑ screen
To calibrate for unknown material velocity
1. Update the transducer zero compensation by wiping the transducer face clean of
all couplant and pressing
[2
nd
F] , [CAL ZERO] (Do ‑ ZERO) .
2. Couple the transducer to the block.
3. Press the [CAL VEL] key.
4. When the thickness reading is stable, press the [ENTER] key.
5. Uncouple the transducer and use the [

] , [

] , [

] , and [

] arrow keys to enter the
thickness of the standard.
6. Press the [MEAS] key to complete the calibration and return to measurement
mode.
If the gage double beeps before returning to measurement mode, then an error has
been made in the calibration procedure and the velocity has not been changed. The
most likely problem is that the thickness value entered was not correct.