Viscopump Parameters - Xylem SI Analytics AVS 370 Manual De Instrucciones

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4.5.4 ViscoPump parameters

The following operating parameters influence the operation of the ViscoPump II and therefore the
measuring process.
The values of these parameters should remain at their preset state and only be changed as
needed!
Sucking over N1
The sample to be measured is suctioned up into the measuring sphere or pressed into it until the
sample reaches the top light sensor (N1). To ensure a reliable measurement process, the liquid is
suctioned a little further, in order to fill the advance sphere, e.g. for Ubbelohde viscometers and to
form a suspended spheric level during the runoff. The duration of the pumping time above the top light
sensor is preset by this parameter. The preset value is 1.
Ramp
When pressing or suctioning the liquid into the measuring sphere, the pressure (or the vacuum
pressure) is increased with time. The speed of the pressure change can be changed via these
parameters. The value 15 % is preset.
Time after measurement
At the end of the measurement of a running time, the liquid meniscus of the sample will trigger the
bottom light sensor. After that, a certain amount of time will pass until the measuring sphere and the
capillary tube have been emptied completely; only after that, the sample can be suctioned back into
the measuring sphere for a repeated measurement. This waiting period can be changed via this
parameter. The value 1 is preset.
Sucking time
®
370 systems, which are connected to a waste system, the parameter "sucking time" defines
For AVS
the suction time for "Rinsing with next sample". This suction time is the running time of a separate
vacuum pump, which suctions the rinsing agent (sample or solvent) into a waste bottle. The suction
time is preset to a value of 100 %. In many cases, a shorter time is sufficient for the suction time in
order to completely suction off the sample. In these cases, we recommend changing the value to
shorten the cleaning process.
Blowing out before measuring
"Blowing out before measuring" can only be activated during the suctioning operating mode. After the
activation, the capillary is blown out for about 1 second before the start of the running time
measurement. This function is used to prevent air bubbles. Air bubbles can be created when sample
residue remains in the capillary after a measurement, which will form air bubbles when the sample is
suctioned up with air afterwards. By blowing out the capillaries, this sample residue is removed so that
no air bubbles are formed.
Enabled sensors
®
There are two safety sensors ("Enabled sensors") that can be connected to the AVS 370: "Safety
®
device" and "Wastebottle". If these sensors are to be used, they must be connected to the AVS
370
and activated under "Enabled sensors".
The status of the sensors can be checked by clicking the "?" to the right of "Waste bottle". If a safety
sensor is connected and has not triggered, it will have a green background, otherwise, it will be red. In
the case shown in Fig. 7, the sensor "Safety device" is connected and activated, but not "Wastebottle".
Fig. 7 Safety sensors