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4.Push VEL-key to exit. If leaving the thickness memory state without pushing VEL-key,
the new measurement value will replace the content of this memory unit.
8. Low voltage indication
If BATT is displayed on the screen, it shows that the battery voltage is running low and the
batteries should be replaced in time before the unit can be used again.
9. Automatic turn off
If no operation is performed within two minutes, the unit will turn off automatically.
10. Measuring technology
10.1 Cleaning the surface
Before measurement, it is necessary to clean the dust, dirt or rusty matters and coatings of the
surface off the test object.
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10.2 Lessening the roughness
Too rough a surface may cause errors or no reading. Before measurement starts, measures should
be taken to keep the test surface smooth by way of grinding, polishing and filing. High viscosity
coupling agent may also be used.
10.3 Roughly machined surface
The regular fine furrows of roughly machined surface (such as machined by lathe or planer) may
also cause errors. The remedy method is similar to 10.2. Better result can also be achieved by
adjusting the intersectional angle between the probe cross talk isolating board (the thin metal layer
on the bottom center of the probe) and the fine furrows of test materials (vertical or parallel). And
select the minimum of the readings as the accurate thickness of the materials.
10.4 Cylindrical surface
It is essential to select the right intersectional angle between the probe cross talk isolating board
and the axial line of the test materials in measuring materials with Cylindrical surface, such as
tubes or barrels. Simply speaking, make the probe coupled with test materials and the probe cross
talk isolating board and the axial line of the test materials parallel or perpendicular and then gently
shake the probe vertically along the direct of the axial line of the test material, the reading will
change regularly. Select the minimum of the readings as the accurate thickness of the materials.
The standard for the intersectional angle is determined by the curvature of the material. For tubular
material with bigger diameters, make the cross talk isolating board perpendicular to the axial line
of the tube; for tubes with a smaller diameters, select two methods (making the intersectional angle
