Elcometer FD700DL+ Operating Instructions Manual page 21

8.8 CALIBRATING - FOR A COATING
Your gauge comes pre-set with a coating velocity of 2159 m s-
approximation of coatings found in the field.
Accuracy may be improved by calibrating for the coating in the same way that a material may be
calibrated for, using either coating velocity or known coating thickness calibration.
• In PECT mode a one point calibration is required
• In CT mode a 2 - point calibration is required.
KNOWN COATING VELOCITY
If the coating velocity is known, you can enter the velocity value into your gauge.
1. Press MENU/CAL / COATING VEL.
2. Press ENTER to display the Digits Edit Box.
3. Adjust to match the coating velocity.
4. Press OK .
5. Press MEAS to return to the measurement screen.
KNOWN COATING THICKNESS
One Point Calibration: Measure a sample of the coating and carry out the calibration using the
same method as for a material, except enter the coating velocity into the "COATING 1PT" area of
the CAL menu. Measure a coating sample on the high side of the measurement range
Note: The coating sample must be coupled to metal in order to calibrate successfully. Place a drop
of couplant on a piece of metal, lay the coating sample over the couplant on the metal and carry out
the calibration
1. Physically measure a location on a coating sample using a set of calipers or a digital
micrometer.
Note: The coating sample must be coupled to metal in order to calibrate successfully. Place a drop
of couplant on a piece of metal, lay the coating sample over the couplant on the metal and proceed
to step 2.
2. Apply a drop of couplant on the transducer and place the transducer in steady contact with the
coating (on metal) 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 MENU/CAL /COATING 1PT function.
4. Press ENTER to display the Digits Edit Box.
5. Adjust to match the coating thickness.
6. Press OK to set the coating velocity and return to the measurement screen, or ESC to cancel.
Note: CHECK YOUR CALIBRATION! Place the transducer back on the calibration point. The
coating thickness reading should now match the known coating thickness sample. If the thickness
is not correct, repeat the steps above.
T - C
WO POINT ALIBRATION
1. Conduct a one point calibration routine as described previously in this section. You should
conduct this routine at the high end of the measurement range.
2. Physically measure the thinner of the two samples of the coating, as close as possible to the
minimum expected coating measurement range, using a set of calipers or a digital micrometer.
- Use the minimum coating sample for the two point calibration.
1
that has been found to be a good
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