Models 947, 948 and 960 Leak Detectors Operations and Service Manual
B-8
11. When installing the ground slit plate, be sure that the snap prongs are facing up.
Align the slit at 90° with the side wall of the spectrometer tube and concentrically align
the circular hole in the plate with the smaller guide hole in the bottom of the ion source
cavity
.
CAUTION
If it is necessary to bend the ground slit plate prongs out, be
sure to bend them only slightly so that when it is being inserted,
the prongs do not scratch the ion source cavity.
12. Check that the ground slit plate is firmly seated in the ion source cavity.
If not, remove he ground slit plate and, using a screwdriver, bend the prongs out
slightly.
Then place it into the cavity again.
CAUTION
A short could result at power up if the alignment pin touches
the sides of the alignment hole.
13. Wipe the new O-ring
➃
and mating surfaces with a clean, lint-free cloth and place
the new ion source in its cavity:
❑
Place the locating pin
➄
so that it falls in the center of the guide hole.
❑
Ensure that pins 1 and 8
➅
are parallel to the sidewall of the spectrometer tube as
shown in Figure B-5 on page B-6, View A.
❑
Secure the flange cap evenly and firmly by tightening the four Phillips head screws.
14. Install the spectrometer tube in the leak detector as described in “Reinstalling the
Spectrometer Tube” on page 4-21.
15. See “Calibration and Sensitivity Checks” on page 3-11 for electronic calibration
procedure.
Summary of Contents for 948
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