Varian 990 dCLD II, Operation Manual

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Model 990 dCLD II Component Leak Detector
4-4
4.1.1 Key Switch
The 990 dCLD II Key Switch allows three different levels of access to the touch panel sys-
tem controls, RUN, SET-UP or SERVICE. Two different keys are provided with the leak
detector:
❑
Key T008 operates the switch in either the RUN or SET-UP positions.
The T008 key is intended for use by a line supervisor or engineer.
In RUN mode (PARALLEL ENABLE is asserted), the control buttons are inoperable,
and the touch panel MENUS box is not displayed on the HOME screen, allowing
access to only SYSTEM and VERSION information. Leak rate can be observed on the
bar graph display, and pressure can be observed on the SPEC-TUBE PRESSURE dis-
play. If it was enabled before PARALLEL ENABLE was asserted, the Audio signal is
operational.
In SET-UP mode, the control buttons for zeroing, calibrating and reading internal leak
are functional, but the balance of the functions are the same as in RUN mode.
❑
Key T009 operates the switch in RUN, SET-UP or SERVICE positions.
The T009 key is intended for service personnel and those who are very familiar with
the operation of the unit, and those who are responsible for setting up and verifying
changes of the operating parameters. All menus and control buttons are operational
in SERVICE mode. RUN and SET-UP modes operate as discussed above.
4.2 Touch Screen Menus
The 990 dCLD II optional front control panel has a touch panel display for the initial setup
and configuration of the leak detector parameters. Once the leak detector is set up, basic
operation and control is taken over by the PLC when PARALLEL ENABLE is asserted. The
instructions below apply to all menus of the touch panel.
4.2.1 Contrast Adjustment of the Touch Panel Display
Press the upper left or right corner of the Touch Panel Home Screen to change the contrast.