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Product description
6924-en_V1.3_09/20
17
3.5
Functional description
The
PMFT 1000 / PMFT 1000 P
is a modularly designed filter testing system
for respiratory masks.
The test rig works in pressure mode.
Aerosol generators
The aerosol is created by two aerosol generators. The aerosol generators
are triggered by a solenoid valve and switched accordingly. The hose con-
nection of the respective generator to to the filter holder must be manually
modified before changing the type of aerosol.
Salts (e.g. NaCL, KCl) and liquid aerosols (e.g. DEHS) can be dispersed.
Recommended concentration for saline aerosols: 5%.
Particle measuring technology
The test rig has an aerosol sampling unit on the clean gas side. An aerosol
spectrometer with aerosol sensor is used to measure the particles.
The particle size and concentration are measured with and without the test
filter to determine the fractional efficiency grade.
Volume flow control
The test rig has two flow controllers (mass flow controllers):
• Mass flow controller 1 to control the main volume flow
• Mass flow controller 2 to control the generator volume flow
Recording sensor data
The test rig has a sensor that measures differential pressure. The values
measured at the filter are automatically recorded during filter testing. Sen-
sors to measure temperature and relative humidity are available as options.