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Product description
3577-en-us_V1.1_08/17
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3.3
Functional description
The
Fidas Frog
is a fine dust measuring device for indoor fine dust measure-
ment. It is a portable, hand-held device. You can use the device at various
measuring sites. The device can operate on battery or on a mains connec-
tion. The device consists of two components: the measuring unit and the op-
erating element.
Operating element
The wireless operating element communicates with the measuring unit via a
wifi connection. Measurements can be taken at a physical distance from the
measuring site. Furthermore, the device can be integrated into an existing
network such as a company LAN. The operating element and measuring unit
are considered clients.
Sensors
The device contains sensors that measure the temperature, air pressure and
relative humidity. The air pressure sensor is installed inside the device.
Volume flow rate
The
Fidas Frog
operates with a volume flow of 1.4 l/min.
Measuring method
A counting measuring method is used. The measuring sensor is an optical
spectrometer.
Individual particles pass through an optical detection zone, the optical mea-
suring volume. The optical measuring volume is evenly illuminated. Light
scatter is generated as the particle passes through the optical measuring
volume. The scattered light pulse is recorded by the device.
• Number of scattered light pulses =
number
of particles
• Signal intensity of the scattered light pulse =
size
of particles
Particle sizes between 0.18 µm and 40 µm can be measured.
Conversion to mass
The measured data for the individual particle sizes is converted to mass by
an algorithm. This algorithm takes into account that the environmental
aerosol is composed of various sources depending on the particle size, for
instance tire abrasion, pollen and combustion.
Several separation curves are also applied to the particle size in order to de-
termine the fractions. Multiple particle size classes are combined into frac-
tions.
The device indicates the following fractions simultaneously:
• PM
1
, PM
2.5
, PM
4
, and PM
10
• TSP (total suspended particles): Sum of all airborne particles in the air-
borne particulate matter
The device also provides the quantity size distribution featuring second by
second resolution.
Data export
The measurement data can be stored. The following file formats are sup-
ported:
• Text file (.txt)
• PDF
• System file (.data.frog)
Use the micro USB serial port to transfer the files to a USB data medium.
If a printer is connected, you can also print the data directly.
Calibration
The measuring device can be checked with the help of test dust and ad-
justed if required.