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Flow Alarm
indicate this on the display and a red light
Overview and User Guide
Installation and Calibration
will show which sensor has a low flow
Guide
condition. If the sensors detect a low flow
condition for more than 20 seconds, then
Alarm Assembly & Connection
an audible alarm will also sound.
When ever a fault condition occurs this is
logged in the alarm's internal memory. A
report of the alarms operation can be
downloaded using a data logging unit and
this information stored on a PC for
maintenance record purposes.
The Sartorius airflow alarm monitors the
airflow condition entering the Safety
Sensor Operation Check
Cabinet and indicates whether there is a
The unit uses two types of ribbon cable:
safe airflow condition for the operator to use
In order to check correct sensor operation
10-way and 14-way. The two 10-way
the system. The cabinet must not be used
cover each sensor opening in turn and wait
cables connect the flow sensors on the
without the alarm in operation, or if the
for a maximum of 20 seconds to see if the
airfoil to the connection box. The 14-way
alarm is displaying an airflow fault
alarm unit responds with a sensor low flow
cable connects the connection box to
condition.
condition.
display unit (as shown below). Also
connected to the display unit is the power
When turned on, the display shows a
To prove effect operation of both sensors
supply. This is where the data logger is
unique serial number for 2 seconds. This is
open the access door to the cabinet and
connected.
a reference number that can be used to
wait for a maximum of 20 seconds, an
identify the installation.
audible alarm will sound to indicate that the
airflow profile coming into the cabinet is not
The display will then show "Stabilising flow
acceptable.
sensors, Please wait 20s". The unit then
checks both the left- and right-hand sensors
in turn and displays their status (i.e., LEFT
OK, etc). If a fault is detected, then the
display will show the sensor name and the
word "faulty" until the fault is cleared.
The unit continues its test on its internal
memory space. If the data storage space
used is > 80%, a warning message will be
displayed showing "> 80% full". When the
internal memory is totally full, a message
warning "Now Full" will be displayed.
After the above test and initialization have
been successfully completed, the unit will
then enter its main monitoring routine.
During normal operating conditions the
alarm display will show "AIRFLOW SAFE" if
the airflow level is lower than the
recommended level, the display will read
"AIRFLOW FAIL" and an audible alarm will
sound.
The flow alarm measures the level of
airflow entering the cabinet. The alarm has
two flow sensors located under the airfoil,
one on either side of the unit. If the airflow
speed drops below 0.3m/s the alarm will
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