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2.00.397 - 1
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User’s Manual
D Ü P E R T H A L S i c h e r h e i t s t e c h n i k G m b H & C o . K G
Frankenstr. 3
63791 Karlstein, Germany
Version March 2022
With restricted or blocked airflow, the pressure difference sensed by the
probe drops. If it drops below the threshold set at the differential pressure
meter, a signal that an error condition has developed is sent into the en-
closure for further processing via the cable in the blue protective conduit.
For technical reasons (hysteresis), the threshold from which the monitor
cancels the error condition when the pressure difference rises again, is
a little higher than the threshold that triggers an error. Therefore, make
sure at all times that the settings for the pressure difference and the fan
speed of the air extraction system on site are matched to each other in
such a way that both an error is indicated when a restriction is detected,
and the error is canceled by the unit when the restriction is cleared. There
is no upper threshold for a maximum pressure difference.
The value of the pressure difference threshold can be set, after opening
the maintenance lid of the compartment with the pressure meter (refer
to Sect. 2.2) from 20 Pa to 300 Pa at this meter. This is done by
simply removing the transparent cover and using a screwdriver
in the provided slot to turn the selector. The factory-set default
threshold of the pressure difference is 40 Pa.
Setting the pressure difference threshold for monitoring the airflow
requires the following steps:
1. Connect the exhaust air monitor properly to the extraction
system (outlet nipple) on site.
2. Set the fan speed to the desired extraction airflow (see
Sect. 3.2.5).
Caution
In a cabinet for flammable liquids, the extraction airflow
has to be sufficient to replace the interior volume of the
cabinet 10 times every hour.
3. Loosen the plastic cover of the differential pressure meter on
the suction hose (refer to the photograph to the right).
4. Using an appropriate screwdriver in the turning selector at the
center of the differential pressure meter, set the threshold to
make “Exhaust OK” appear on the screen (reduce pressure
difference). If no error is displayed on the screen at the start,
the pressure difference setting may first be increased until
an error is displayed, then slowly reduced again. The higher
the pressure difference threshold is set, the quicker / more
sensitive the meter will respond by throwing an error message.
5. Using appropriate means on site (e.g. by covering the exhaust outlet
with your hand), interrupt the extraction airflow temporarily.
6. If set correctly, the unit will trigger an alarm indicated by the statusd
LED. After the airflow interruption is cleared, the unit should return
to normal operation.
7. Reinstall the plastic cover on the differential pressure meter.
3 Operation
Caution
Be sure that all provisions of Sect. 1.1 and 1.2 above are
strictly complied with for both the installation and the op-
eration. Failure to do so may expose you to hazardous
situations.
Info
Immediately after switching the monitor on, all warning and
status LEDs remain lit for 30 sec for verification.
Latch clips to hold/remove
the plastic cover
Selector for setting the
pressure difference threshold
