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The gauge then try to set up a connection with the mini-printer via Bluetooth. Wait for several seconds.
When the Bluetooth status light on the front panel of the main unit is always on, the Bluetooth connection
between the instrument and the mini-printer is established successfully.
Print stored data group via Bluetooth.
In the memory manager dialog box, select “print” will
print the selected data group. Select “Print All” will print
all data groups stored inside the instrument.
You can also print out the test result directly after each
test.
Note: When the instrument is turned off and once again turned on, the Bluetooth function
module will be automatically shut off to save power.
5 Operation
Caution: Insufficient preparation of the test procedure may damage to the unit and/or the sample to be
measured.
Before each test procedure:
Clean if necessary.
Carry out performance check.
Check or change settings (impact device, impact direction, materials, scales, etc. ).
5.1 Preparation of the sample
Preparation for sample surface should conform to the relative requirement in the Appendix Table 3.
5.1.1 Weight and thickness of the test piece
Place specimens under 5kg on a solid base so that they cannot be moved or oscillate as a result of the
impact. Firmly couple specimens that weigh between 0.1-2kg to an immovable base, e.g. a heavy base
plate.
Despite the low mass of the impact body and low impact energy, a relatively large impact force of short
duration is generated when the impact body hits the measuring surface.
Impact device
types
Classification of samples
Max. impact
force
heavy
Medium-weight
Light-weight
D/DC, DL, E
More than 5.0 kg
2.0 – 5.0 kg
0.05 – 2.0 kg
900N≈90kgf
G
More than 15.0 kg
5.0 – 15.0 kg
0.50 – 5.0 kg
2500N≈250kgf
C
More than 1.5 kg
0.5 - 1.5 kg
0.02 – 0.5 kg
500N≈50kgf
For heavy samples of a compact shape, no particular precautions are necessary. Smaller and lighter
samples or workpieces yield or flex under this force, producing HL values which are too small and of
excessively large variation. Even with big or heavy workpieces, it is possible for thin wall regions or
thinner protruding parts to yield upon impact. Depending on the frequency of the resulting yielding action,
the measured HL value may be too small or too large.
In many situations, potential problems can be checked in the following manner:
Medium-weight samples and also heavier samples with protruding parts or thin walls should be
placed on a solid support in such a manner that they do not move or flex during the test impact.
Light-weight samples should be coupled with a non-yielding support such as a heavy base plate to
guarantee that they are rigid. Clamping in a vice is of no value, since the samples become exposed
to stress and because complete rigidity is never attained, resulting in measured HL values which
would be too high and show excessive variations.
Note: Thin areas or parts can oscillate slightly upon impact, even in the case of heavy or
medium-weight workpieces. This can lead to incorrect values and a clanking noise when an
impact is carried out.
