Ulvac HELIOT 301, Инструкция по эксплуатации

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4-6-6 Zero tracking function
This function resets the leak rate display to zero during test. Use it after fully understanding
the following
Pressing the zero switch
″
0
″
during test displays
″
#
″
at the head of the leak rate display on the
LCD screen and
″
0.0E-**
″
. This activates the zero tracking function.
This function is best suited to an application where it is desired to display only the change in
values when helium is used, as against to the measurement value before use of helium
(background) as reference. If this function is activated when the background has lowered
sufficiently and is stable, the value will be zero and, after that, only changes are displayed.
When this function is activated,
″
#
″
will be displayed and the mantissa of the value will be
″
0.0
″
. The multiplier lowers by one digit from the displayed digit. If, for example, E-8 is
displayed, E-9 will be displayed by activating this function. Since the change in multiplier
depends on the resolution of individual instruments, it may lower from E-8 to E-10 or may
not lower from E-8 depending on the condition.
A second press on the zero switch when
″
#
″
is displayed (when function is ON) extinguishes
″
#
″
and deactivates the function. If the function is deactivated, the background will be
redisplayed, allowing the current background to be checked easily.
If the timing of activating the function is not appropriate, even the measurement value will be
zeroed. The operator should be aware of this problem before using it.
Auto flow middle
3.8E-05 Pa·m
3
/s
1) Under test. Press the zero switch .
↓
Press
Zero adjusting
3.8E-05 Pa·m
3
/s
2) Adjust the zero point.
↓
Auto flow middle
#0.0E-06 Pa·m
3
/s
3)
″
#
″
is displayed and the zero tracking function is activated.
The mantissa is
″
0.0
″
and the multiplier is
″
06
″
.
↓
Press
4) Press the zero switch for a second time.
Auto flow middle
3.8E-06 Pa·m
3
/s
5) The zero tracking function is deactivated and the original
background is displayed.
″
#
″
disappears.
* The zero tracking function cannot discriminate between the background value and test
measurement value. If the function activating timing is not appropriate, the measurement value
will be zeroed. The operator should be well aware of this problem before using this function.