Varian 947, Руководство по эксплуатации и обслуживанию

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Models 947, 948 and 960 Leak Detectors Operations and Service Manual
3-6
AUTO-SEQUENCER Provides clear accept/reject signals and allows
programming for roughing, testing, and cycling times. Auto
sequencer provides the ability to set up the 947/948/960 so
that it automatically runs through a complete test cycle
(START/ROUGH/TEST/VENT), passing or failing the test part
per the test specification entered by the user. The auto
sequencer set-up controls include test object rough time,
test time, and auto sequencer on/off. A Pass or Fail
condition is determined based upon the reject set point
selected by the user and/or achievement of the pressure
transfer set points within the period of time specified in
Rough Time.
The auto sequencer pass or fail leak rate value is selected
through the Reject Set Point. The pass/fail criterion is based
on the reject set point that is enabled (ON). If more than
one set point is enabled, then the pass/fail criterion is based
on the most stringent reject set point value.
A Pass condition is indicated by the system reverting to the
VENT mode upon completion of the test cycle. A fail
condition results in REJECT being displayed in the LED
display area, and a reject set point activation upon
completion of the test cycle. A Fail condition is also
indicated by the system reverting to the HOLD mode, and
all operating buttons being disabled except VENT. The
status of the reject set points is available at the optional I/O
communications port (host computer) and upon inquiry
through the service pendant (Appendix A, “Service Pendant
Keypad Functions”).
Upon the completion of an automated test cycle, the
947/948/960 captures the leak rate signal measured just
prior to the end of the automated test cycle. This leak rate is
displayed and held at the analog output communications
port until the next test cycle is initiated. This allows the end
user to record the actual leak rate value for each test object.