Model 11-R
GRIMM AEROSOL TECHNIK GmbH & Co.KG Seite 81 von 83
7.5 Zero filter (model 1148)
This filter is used to test the dust monitor for interference in the sig-
nal electronics and leaks in the suction system. When the filter is
connected to the air intake on the dust monitor, the concentration
measurements on the display have to go to zero after a minute due
to averaging or immediately in case of online measurement. The
increase in the pump motor current up to 60%, which may be ac-
companied by a warning, is normal here.
7.6 Temperature and relative humidity sensor (model 1158-EE)
This sensor due to its low power input is ideal as an accessory for all dust monitors. The sensor values
can be shown online on the display, via HyperTerminal or in the sensor window of the GRIMM Windows
1178 software. Knowledge of the relative humidity is fundamental for the interpretation and analysis of
aerosol measurement data.
= 12 mm, length = 83 mm, cable: approx. 1.5 m
0 to 100 % relative humidity
Accuracy:
Temperature dependen-
cy:
Typically 2 %
Typically 0.03% relative humidity/K
Figure 7-10: Zero filter
Figure 7-11: Sensor
1158-EE