Checkline TI-CMXDLP - Manual (Page 38)

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range is .100” (2.54mm) to 1.0” (25.4mm), the user should calibrate on a known
thickness sample close to 1.0” (25.4mm).
NOTE: It’s always handy to carry a set of mechanical calipers to use in conjunction
with the TI-CMXDLP for calibration in the ield.
One Point Calibration
NOTE: Be sure that the probe zero procedure 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. Press the MENU
key once to activate the menu items tab. Press the
MENU key multiple times to tab right and the ESC
key multiple times to tab left until the CAL menu is
highlighted and displaying the submenu items.
3. Use the UP and DOWN arrow keys to scroll through
the sub menu items until MATL 1PT is highlighted.
4. Press the ENTER key to display the Digits Edit Box.
5. Press the UP and DOWN arrow keys to scroll the
highlighted value.
6. Press the LEFT and RIGHT arrow keys to scroll the
digit locations.
7. Repeat steps 5 & 6 until the known thickness value is
correctly displayed.
8. Press the OK key to calculate the velocity and return
to the menu screen, or ESC to cancel the one point
calibration.
9. Finally, press the MEAS key to return to the
measurement screen and begin taking readings.
NOTE: CHECK YOUR CALIBRATION! Place the
transducer back on the calibration point. The thickness reading should now match the
known thickness. If the thickness is not correct, repeat the steps above.
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6. Repeat steps 4 & 5 until the velocity number is correctly
displayed.
7. Press the OK key to set the velocity and return to the
menu screen, or ESC to cancel entering the velocity.
8. Finally, press the MEAS key to return to the
measurement screen and begin taking readings.
Known Thickness
Sometimes the sound velocity of a coating material is
unknown. In this case a sample with a known thickness can
be used to determine the sound velocity of the coating. As previously discussed, the
TI-CMXDLP offers a one point calibration option for coating in PECT measurement
mode. It is also import to reiterate that the coating sample must be coupled to a metallic
material in order to perform the calibration. The calibration should also consider
calibrating on high side of the intended measurement range, when using the one point
option, minimize overall error. For example, if the measurement range of the coating
will be from .040” - .080” (1.0mm – 2.3mm), a coating closest to .080 (2.0mm)
should be used. Note: It’s always handy to carry a set of mechanical calipers to use in
conjunction with the TI-CMXDLP for calibration in the ield:
One Point Calibration
NOTE: Be sure that the probe zero procedure has been performed prior to performing
this calibration procedure.
1. Physically measure an exact sample of the coating using a set of calipers or a digital
micrometer.
NOTE: The coating sample must be coupled to a metallic
material in order to be calibrated.
2. Apply a drop of couplant on a piece of metal and place
the coating sample on the metal over the couplant. Apply a
drop of couplant on the transducer and place the transducer
in steady contact with the coating and 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. Press the MENU key once to activate
the menu items tab. Press the MENU key multiple times to
tab right and the ESC key multiple times to tab left until the
CAL menu is highlighted and displaying the submenu items.