O
PERATION
M
ANUAL
VKL
10
/100
V
ERSION
V005-06-2020
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7.2. Filter Control and Filter Change
7.2.1. Filter Control
The lifetime of the filter depends first of all on the quality of the compressed air used. When
using pre-cleaned and dried compressed air, the lifetime will last for several years.
The proper functioning of the filter can be checked as follows:
- clean dilution stage
- connect compressed air which will also be used for the measuring
- fit an "absolute filter" on the inlet nozzle
- connect particle counter to outlet nozzle
- set dilution system into operation and use the OPC to measure particle concentration in
the mixing chamber
After operating for about 10 minutes, the measured concentration should be less than 10
particles per liter. If the resulting concentration is considerably higher, we recommend to
contact the manufacturer first.
7.2.2 Filter Change
If a filter change becomes necessary, follow the below instructions:
- completely unscrew filter screw counterclockwise
- take out filter with O-ring
- insert new filter with O-ring (arrow pointing downwards)
- position filter screw and screw in
- tighten filter screw only slightly; about flush with casing.
Since the flow channels were exposed during the change to environmental air, run dilution
stage for about 15 minutes at medium pre-pressure for flushing. New filters with O-rings
are available from the manufacturer.