PCE Instruments PCE-CT 100, User Manual

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6.3 One-foil calibration (2-point calibration)
The one-foil-calibration has to be done on an uncoated sample (as with the zero setting).
For the one-foil-calibration, choose a calibration foil that comes closest to the expected coating
thickness.
Procedure:
1. Carry out ‚zeroing’ (1-point calibration) as described above (please see chapter
6.2).
2. Press Arrow Down key; “Calibration” appears on the display
3. Press OK key; “Zero setting” appears on the screen
4. Press Arrow Down key one more time; “ONE-foil calibration” appears on the screen
5. Press OK key; “Place probe on foil standard” appears on the display and the CAL icon in the
display starts to flash
6. Put the measurement foil on the uncoated test object and place the probe on the foil several
times
7. Press OK key; “Set standard value” appears on the display
8. Use the arrow keys to enter the calibration foil thickness as indicated on the standard
9. press this key; Calibration has been set appears briefly on the display followed by the start
screen with the four dashes – – – – . The CAL symbol is visible permanently.
You can now measure using the ONE-foil calibration.
6.4 Two-foil calibration, e. g. for rough surfaces
This calibration mode is used especially for the measurement on rough surfaces, e. g. on sand-
blasted base metals. It is also suitable for low-intensity magnetic samples when carrying out the
measurement either according to the magnetic-inductive method or according to the eddy current
method.
In this calibration mode, two calibration foils varying in thickness are used. The thickness of the
foils should be selected in a way that the thickness of the thinner foil is 0.5 to 0.9 times that of the
expected coating thickness and the thickness of the thicker foil is 1.1 to 1.5 times that of the
expected coating thickness.
Procedure:
1. Press Arrow Down key; “Calibration” appears on the display
2. Press OK key; “Zero setting” appears on the screen
3. Press Arrow Down key twice until “TWO-foil calibration” appears on the display
4. Press OK key; “Place probe on 1st foil” appears on the display.
5. Put one of the two calibration foils on the uncoated sample and place the probe on the foil
several times
6. Press OK key; “Set standard value” appears on the display
7. Use the arrow keys to enter the calibration foil thickness as indicated on the standard
8. Press OK key; “Place probe on 2nd foil” appears on the display
9. Put the second calibration foil on the uncoated sample at the same point and place the probe
on the foil several times
10. Press OK key; “Set standard value” appears on the display
11. Use the arrow keys to enter the calibration foil thickness as indicated on the standard
12. Press OK key; “Calibration has been set” appears on the display for a short time, followed
by the start screen with the four dashes – – – –
You can now measure using the two-foil calibration. In measurements on rough base materials,
the average coating thickness is measured across the peaks. The measuring uncertainty
increases with increasing roughness.