Varian 990 dCLD II, Operation Manual

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Model 990 dCLD II Component Leak Detector
6-6
11. If EMISSIONCURRENT is zero, the selected filament in the Ion Source is broken or the
Ion Source is defective. Issue the INIT-FILAMENT<CR> command to change to the other
filament, or replace the Ion source (Section 5.5 “Ion Source Replacement Outside of
Spectrometer Tube Overhaul” on page 5-19).
12. Has the spectrometer tube been serviced lately? If so, refer to Section 5.3 “Spectrometer
Tube Overhaul” to verify that:
❑
The ground slit plate has been properly positioned (Figure 5-21 on page 5-17).
❑
The ion source is correctly aligned (Figure 5-21 on page 5-17).
❑
That the magnet pole piece inserts are fully inserted and secured in place with set
screws).
If there is still no helium response, call Varian Customer Service at 1-800-8VARIAN
(1-800-882-7426).
6.2.4.2 Check the Helium Response
Using the Optional Front Control Panel Interface
To check the helium response:
1. Use the LEAK RATE RANGE SET-UP screen, Section 4.6.4 “Range Stop and Manual
Range Set Up and Control” on page 4-15, to ensure that MANUAL RANGE is not ON. If
necessary, turn it OFF.
2. Check that the leak to be read is installed in the system with the valve open.
3. Is the calibrated leak broken? Has the calibrated leak been dropped? If it rattles when
shaken, it is broken and must be replaced.
4. Is the spec tube pressure shown on the Spec-Tube Pressure display minimum and stable?
(See Figure 4-1 on page 4-1.) Does the Home Screen display SYSTEM READY? (See
Section 4.4 “Touch Panel Home Screen” on page 4-7.)
5. Is the leak rate shown on the bar graph display stable? (See Figure 4-1 on page 4-1).
6. Are the valves in the system operating correctly? Check that the valves are properly
oriented and actuating when commanded.
7. With the leak valved off, press the ZERO button to ZERO the 990 dCLD II.
8. Move to the MANUAL TUNING screen, Section 5.6 “Manual Tuning” on page 5-20,
and change the ION V value to 250, REPELLER V to 380, VAR FOCUS to 200,
EMISSION I to 400 and touch
OK .