SRS Labs QMS 100 Series, Руководство пользователя

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Cleaning 5-15
Technical Reference
Warning:
The fumes from isopropyl alcohol can be dangerous to health if inhaled and are highly
flammable. Work in well ventilated areas and away from flames.
Warning:
Read and follow all directions and warnings of the ultrasonic cleaner regarding the use of
organic solvents for cleaning.
Equipment
•
Ultrasonic cleaner
•
Isopropyl alcohol, electronic grade or better.
•
1000 ml beaker
•
Oil-free, dry nitrogen
•
Petri dish.
•
Clean oven ( higher than 100
°
C setting).
Procedure
1. Fill the 1000mL beaker with isopropyl alcohol.
2. Gently place the CDEM into the alcohol.
3. Insert the beaker containing the CDEM into the ultrasonic cleaner for 10 minutes
4. Remove the CDEM from the isopropyl alcohol and allow it to drain for a few minutes
5. Depending on the contamination level, repeat steps 1-4 as needed.
6. Blow dry the CDEM with oil-free dry nitrogen.
7. Place the CDEM in a clean Petri dish and dry at 100
°
C for about one hour.
Quadrupole Filter Cleaning
The quadrupole mass filter is the heart of the RGA. The sensitivity and resolution of the instrument are
ultimately limited by the quality of the quadrupole field between its rods. Deposits on the rods
accumulate electrostatic charge and distort the field, resulting in degraded performance. The deposits
typically form at the entrance to the mass filter, when the RGA is operated at high pressures or over
long periods of time. They are often seen as a discoloration of the metal but in some cases (i.e.
depending on the vacuum composition) they are invisible.
If contamination of the rods is suspected, the first step to take is a one- or two-day long bakeout. If
bakeout is not successful, the quadrupole filter will need to be cleaned. Note that in order to clean the
rods, the entire quadrupole head assembly must be taken apart, and unless the exact nature of the
deposits is known, the only sure way to remove them will be with a very fine abrasive.
Warnings: