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Light-weight sample must be firmly coupled with a heavy base plate. Both coupled surfaces must be flat and
smooth. And there should be no redundant coupling agent exists. The impact direction must be vertical to the
coupled surface.
●
When the sample is a big plate, long rod or bending piece, it can be deformed and become unstable, even
though its weight and thickness is big enough, and accordingly, the test value may not be accurate. So should be
reinforced or supported at its back.
●
Magnetism of the sample itself should be avoided.
4.1.2 Preset test parameters
See 6.8.
4.2 Testing
The instrument can be calibrated with standard test block, the accuracy and repeatability displayed
should be within the regulation of table 5.
4.2.1 Loading
Put the supporting ring onto the surface of workpiece
，
hold the concave area by left hand
，
and press
down the body by right hand while holding the loading key
；
Impact direction should be vertical to tested surface.
4.2.2
Testing
Press release button at top of the main unit to test. The sample and the main unit as well as the
operator are all required being stable
；
