F
8
EN
2.00.390C - 1 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
that the fan speed and the pressure difference threshold have
to be matched to each other. If this were not the case, there
would be a risk of getting false alarms.
2.2 Monitoring Unit Components
2.3 Understanding Operation
After the On/Off switch was pressed to turn the unit on, the fan located
inside the enclosure of the airflow monitor draws air from the monitored
system through the suction hose connected to the inlet nipple and ex-
tracts the air from the system via a filter setup through the output of the
enclosure (see Figures in Sect. 2.2).
If an error condition develops for any reason, airflow through the line
is restricted to a greater or lesser extent, and this causes the pressure
difference measured in the suction hose to drop. If the pressure differ-
ence drops below the preset threshold, an audible alarm and a visual
alarm are triggered.
If an error condition occurs, first the problem has to be cleared to re-
enable proper airflow through the exhaust line. Then, as shown on the
Potential-free (“dry”) Contacts
Opening (outlet) for filtered
exhaust air
Suction Hose
(Inlet) with
Pressure Differ-
ence Switch/Meter
On/Off Switch and
Power Supply Port
Name
Plate w/ Serial No.
Optional Connectors
Display
Screen
STOP/RESET and
START/SET Keys
Display and Control
Panel on Unit Front
Cursor/Arrow
Keys
Front View
Back View
Top View
Where presses of
the cursor keys
are referenced
b e l o w i n t h i s
manual, they are symbol-
ized by arrow characters:
Key LEFT
Key RIGHT
Key UP
Key DOWN
See Sect. 3.2.6 for more
detailed explanations of the
power socket at the back to
which a Cool Line refrigerator
cabinet can be connected.
Summary of Contents for HNA-18 II ATEX F
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