Ulvac HELIOT 301, Instruction Manual

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Case 5 (Leak test of other equipment)
• Testing conditions
Leak test of vacuum chamber
• Acceptance criterion
The leak rate is to be not more than 5.0E-08 Pa·m
3
/sec.
• Recommended setting
Sensitivity L
Auto flow
Auto range
Linear display
• Explanation
ＨＥＬＩＯＴ
ＩＮＳＴＲＵ−ＭＥＮＴ
Recommended sensitivity setting is L because the acceptance
criterion is on order of E-8.
Set auto flow corresponding to all pressures below 1000 Pa.
The recommended display is linear display that can display each
multiplier range minutely and the recommended range is the auto
range that permits automatic changeover.
Since the pumping system for the chamber is operating
independently of HELIOT, consider at which point of the
equipment HELIOT is to be connected, referring to Case 5.
It is also to be noted that when making leak test of a component with the instrument running,
it must be shut down before movement, but when test is completed, the test port is vented to
atmospheric pressure. The running equipment will be vented to atmospheric pressure by just
completing the test before it is moved.
To solve this problem, provide a valve between the chamber and HELIOT. Connect the
chamber and HELIOT by means of piping with this valve closed and start up each of them to
put HELIOT in a testing condition (roughing completed) and then open the valve and make
leak test by connecting the chamber and HELIOT. Upon completion of leak test, close the
valve and press the vent switch on HELIOT to terminate the test. This allows HELIOT to be
shut down and moved without venting the chamber to atmospheric pressure.