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4-6-4 Middle leak flow
This flow executes roughing after start of test and changes over the mode to test automatically
when the test port pressure has come down to below 70 Pa.
It is suited to an application where the ultimate pressure of the test object does not reach 10 Pa.
In this application, leak test can be made under more favorable conditions (higher minimum
resolution) as compared with gross leak flow.
If a pressure rise that exceeds 70 Pa occurs after start of test, test will be assumed to be
unexecutable and error processing of test stop will be made, allowing it to be utilized for the
monitoring of pressure rise.
The following is an example of middle leak flow when the SEN. switch is set at L.
Test mode L
Standby
1) Start test from test mode standby. Securely connect the test
object to the test port.
↓
Press
2) Press the test switch
once. Test starts.
Middle leak flow
Evacuating
↓
↓
3) Work is rough-pumped (evacuated). If the pressure does not
come down to below 70 Pa within three minutes, error
processing is made for the roughing fault and stops and
invalidates the test.
Middle leak flow
Change Grs. flow
4) Roughing is completed and middle leak flow starts.
↓
Middle leak flow
*.*E-** Pa·m
3
/s
↓
Press
5) Test is being made by middle leak flow. Middle leak flow is
continued in this condition even if the test port pressure comes
down to below 10 Pa.
Test mode L
Standby
6) To end the test, press the vent switch
. The test port is
vented to atmospheric pressure simultaneously with
completion of test, returning to test mode standby.
* If pressure does not come down to below 70 Pa within three minutes after start of test, test will be
stopped and invalidated, displaying the error message "Evacuation fault".
* If pressure exceeds 70 Pa after starting test, test will be stopped and invalidated, displaying the
error message "M. flow invalid".
Summary of Contents for HELIOT 301
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