Ulvac HELIOT 301, Instruction Manual

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Case 2 (Test object with large capacity)
• Testing conditions
Measure the leak rate of a closed container of about one litre to decide whether the test object
is OK or NG.
• Acceptance criterion
The leak rate is to be 5.0E-08 Pa·m
3
/sec or less.
• Recommended setting
Sensitivity L
Gross leak flow
Fixed range (E-08)
Linear display
Setpoint (5.0E-08)
• Explanation
Recommended sensitivity setting is L because the acceptance criterion is on order of E-8.
Because of the large capacity of the test object, the roughing time should take long. To start
test as soon as possible, set gross leak flow (or auto flow) that permits start of test from 1000
Pa. Since the standard sensitivity range of gross leak flow is on order of E-9 to E-4,
measurement can be made with no problem against this acceptance criterion.
Since this test is made to only judge if the measurement value is above or below the
acceptance criterion, set the LED bar graph at the level of the acceptance criterion (E-8).
Thus all you do is just check if the LED bar graph display is above or below 5.0.
Once you set the setpoint value to the criterion value, the buzzer can be sounded or the lamp
be lit when the result of inspection is NG by utilizing the setpoint signal of the output signal.
In this manner, you can make OK/NG decision of the test object only with the aid of the
buzzer and lamp without being bothered by the measurement value in each test.