DH Instruments ADCS-601, Руководство по эксплуатации и обслуживанию

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ADCS-601™ OPERATION AND MAINTENANCE MANUAL
© 2005 DH Instruments, Inc. Page 66
To delete a user, select the user from the <Supported Users> list and then
press the [DELETE] button.
To edit a user, select the user from the <Supported Users> list and then begin
editing as desired. The red, flashing <Editing User> bar appears. When editing
is complete, press the [Save] button to save the new user.
4.2.8.2 CHANGING ACTIVE USER
When ADCS Tools is started up a user must be specified in the [User Login]
dialog box.
To change active users, press [Setup] , [Change Current User] to cause the
[User Login] dialog box to appear.
4.2.9 PRESSURE LEAK TEST
It is good practice to run a leak test on the ADCS-601 after performing a setup or maintenance
operation that requires pressure fittings to be disconnected. The leak test can quickly determine
if the ADCS-601 is performing properly. A report detailing the status of the individual portions of
the leak test is provided upon test completion. The information in this report is used to isolate
leaks in the ADCS-601 system (see Figure 31).
To run a pressure leak test, first put in the ADCS-601 in absolute measurement mode (see
Section 4.2.3). After at least one hour in absolute mode, press the
[Leak Test] button on the
ADCS Run Screen Toolbar (see Section 4.3.5.3). User confirmation is required to ensure that
there are no DUTs connected to the ADCS-601 that cannot support the leak test pressure.
During the leak test, pressures of 375 kPa (110.7 inHg) and 15 kPa (4.4 inHg) are set.
Do not attempt to run a leak test until the ADCS-601 has been in absolute measurement
mode for at least 1 hour. The residual vacuum reference can change significantly during
the first hour of absolute measurement mode operation after transitioning from gauge
measurement mode. This change in pressure can cause the leak test to fail.
There are three parts to the leak test: PG7601 drop rate test, residual vacuum test and FPG
lubrication flow test. If any part of the leak test fails, the overall leak test fails.
The PG7601 drop rate portion of the leak test sets a high and low pressure with the PG7601.
After stability is achieved the change in piston position over a 30s interval is used to
determine the drop rate of the piston-cylinder. The recorded drop rates are compared to
factory defined drop rate limits to determine a PASS/FAIL status. A high piston drop rate
indicates a leak in the pressure circuit that interconnects the TEST(+) port, the PG7601 and
the PG7601 pressure controller.
The residual vacuum portion of the leak test records the FPG8601 and PG7601 vacuum
reference sensor outputs when the FPG8601 bypass valve is closed. The residual vacuum
test is executed during the high pressure portion of the PG7601 drop rate test. The recorded
residual vacuum pressures and the difference between them must fall below factory
determined limits to pass the residual vacuum portion of the leak test. The residual vacuum
test fails when a leak into the vacuum reference circuit is present.
The FPG8601 lubrication flow portion of the leak test is executed while the PG7601 drop rate
test is setting the high pressure. In this test, the FPG8601 bypass valve is closed to monitor
the rate of increase in the FPG8601 pressure due to the lubrication flow. Without pressure
control, the FPG8601 pressure increases as a result of the FPG8601 lubrication flow when
the FPG8601 bypass valve is closed. The change in the indicated FPG8601 pressure is
recorded over a 30s interval to determine the pressure rate of change caused by the
lubrication flow. The recorded value must fall below factory defined limits to pass the
FPG8601 lubrication flow portion of the test. A failure indicates a leak in the pressure circuit