Elcometer 207 Operating Instruction page 18

5.1 KNOWN THICKNESS CALIBRATION
This procedure requires a sample piece of the material to be measured, the exact thickness of which is
known, e.g. from having been measured by some other means.
1. Switch on the gauge.
2. Apply couplant to the sample piece.
3. Press the transducer against the sample piece, making sure that the transducer is flat against the
surface of the sample. The display should show some (probably incorrect) thickness value, and nearly
all the bars of the stability indicator should be illuminated.
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 and 4.
5. Press the CAL key. The MM (or IN) symbol should begin flashing.
6. Use the UP and DOWN arrow keys to adjust the displayed thickness up or down, until it matches the
known thickness of the sample piece.
7. Press the CAL key again. The M/s (or IN/µs) symbols should begin flashing. The gauge is now
displaying the sound-velocity value it has calculated.
8. Press the CAL key once more to exit the calibration mode.
The gauge is now ready to perform measurements.
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