Checkline TI-007DL - Manual (Page 7)

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Calibration to a known thickness
NOTE: This procedure requires a sample piece of the specific material to be mea-
sured, the exact thickness of which is known, e.g. from having been measured by some
other means.
1. Make sure the TI-007DL is ON.
2. Apply couplant to the sample piece.
3. Press the transducer against the sample piece, making sure that the transducer sits
flat against the surface of the sample. The display should show some (probably
incorrect) thickness value, and the Stability Indicator should have nearly
all its bars on.
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.
5. Press the CAL key. The IN (or MM) symbol should begin flashing.
6. Use the UP and DOWN arrow keys to adjust the displayed thickness up or down,
until it matches the thickness of the sample piece.
7. Press the CAL key again. The IN/µs (or M/s) symbols should begin flashing.
The TI-007DL is now displaying the sound velocity value it has calculated based on
the thickness value that was entered in step 6.
8. Press the CAL key once more to exit the calibration mode. The TI-007DL is now
ready to perform measurements.
Calibration to a known velocity
NOTE: This procedure requires that the operator know the sound-velocity of the mate-
rial to be measured. A table of common materials and their sound-velocities can be
found in Appendix C.
1. Make sure the TI-007DL is ON.
2. Press the CAL key to enter calibration mode. If the IN (or MM) symbol is flashing,
press the CAL key again, so that the IN/µs (or M/s) symbols are flashing.
3. Use the UP and DOWN arrow keys to adjust the displayed velocity up or down,
until it matches the sound-velocity of the material to be measured.
4. Press the CAL key once more to exit the calibration mode. The TI-007DL is now
ready to perform measurements.
NOTE: At any time during the calibration procedure (IN, MM, IN/µs, or M/s flashing
in the display), pressing the SCAN key will restore the tool to the factory default
sound-velocity for steel (0.233 IN/µs).
To achieve the most accurate measurements possible, it is generally advisable to
always calibrate the TI-007DL to a sample piece of known thickness. Material
composition (and thus, its sound-velocity) sometimes varies from lot to lot and from
manufacturer to manufacturer. Calibration to a sample of known thickness will ensure
that the tool is set as closely as possible to the sound velocity of the material to be
measured.
7. Press the UP/DOWN arrow keys to scroll to the flashing Prnt/F-05
(the file chosen), or LISt (tape printer) symbol.
8. Press the SEND key to print the contents of the file.
9. Press the MEM key at any time to exit the data logging functions and return to
measurement mode.
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