phase II 900-398, Manual, Page: 10 / 20

Tech Support
10
Macro Vickers
Model No. 900 ‐ 398
Hardness Tester
NOTE: 1. When toggling between the objectives 10
╳
and 20
╳
, there might be a
slight change in the vision field. Just adjust slightly the up-and-down lead-screw until the focusing plane is clear.
2. When testing indentation size covers over 60% of the vision field, the hardness value for this
measurement is erroneous
You can have 2 choices:
a) Reduce the testing force;
b) When it is stipulated that the testing force can’t be changed in the
technical file, you must choose the objective with small rate amplification. This is the function
that both objectives can measure.
3.1.7 After the focusing operation is finished, turn the indenter to the front of the
instrument .At this point,the distance between the tip of the indenter and the plane
of the specimen is about 0.4
～ 0.5 mm. When an irregular-shaped specimen is to be
tested, take care not to damage the indenter. The indentor must be perpendicular to
the surface at all times.
3.1.8 According to the requirements of the test, set the dwell time of the test force with
the keys on the operating board. Each push of the button accounts for 5 seconds,
with the key
“ TIME+ ” adding time and the key “ TIME- ” reducing time.
3.1.9 Press the key “START” on the operating board and apply the test force; at this point
(LOADING) LED is lit.
3.1.10
Af
ter the test force is applied, DWELL LED lights up. At this time the LCD screen
shows the dwell countdown of the time selected. When the dwell time is up, the test
force UNLOADING LED lights up. After test force UNLOAD LED lights out,
shift the objective selected to front of instrument .
NOTE: When the UNLOAD LED is still on, do not turn the protecting cover of the
indenter; otherwise it would cause damage to the instrument. After pressing
the “START” Key, if you find the objective is in front of instrument instead
of the penetrator, Please be patient to wait until the machine performs the
test cycle. DO NOT ROTATE DURING TEST. Serious damage can occur
3.4.11 Rotate the turntable counter-clockwise to place the 20 ╳ objective in front of the main body. Turn the drum
wheel on both left and right side of micro eyepiece, so that the operator could see the two graduated lines move
closely as shown in Fig 6. Continue turning eyepiece until the inner sides of graduated lines reach critical state
with no space between them to allow the light to penetrate as shown in Fig 7. Now press the SPEC key and
then press “CLR-D” key to clear the zero, at this point, it has finished to set zero for the eyepiece, the values of
D1 and D2 will show 0.00 on the LCD screen.